Reproducibility and stability of deep inspiration breath hold and free breath in breast radiotherapy based on real-time 3-dimensional optical surface imaging system

Reproducibility and stability of deep inspiration breath hold and free breath in breast radiotherapy based on real-time 3-dimensional optical surface imaging system | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Reproducibility and stability of deep inspiration breath hold and free breath in breast radiotherapy based on real-time 3-dimensional optical surface imaging system Junxiang Wu, Feng Yang, Jie Li, Xianliang Wang, Ke Yuan, Lipeng Xu, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4962651/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 11 Nov, 2024 Read the published version in Radiation Oncology → Version 1 posted 14 You are reading this latest preprint version Abstract Background The aim of this study was to evaluate the inter-fraction reproducibility and intra-fraction stability of breast radiotherapy using deep-inspiration breath hold (DIBH) and free breathing (FB) based on an optical surface imaging system (OSIS). Methods Seventeen patients (510 breath-hold sessions) treated using a field-in-field (FiF) technique and twenty patients (600 breath-free sessions) treated with a volume-modulated arc therapy (VMAT) technique were included in this retrospective study. All the patients were positioned with the guidance of CBCT and OSIS, and also monitored with OSIS throughout the whole treatment session. Eight setup variations in three directions were extracted from the treatment reports of OSIS for all sessions and were subsequently manually introduced to treatment plans, resulting in a total of 296 perturbed plans. All perturbed plans were recalculated, and the dose volume histograms (DVH) for the target and organs at risk (OAR) were analyzed. Results The OSIS and CBCT for both DIBH and FB treatments showed a good agreement of less than 0.12 cm in each direction. The intra-fraction setup errors during DIBH were − 0.06 ± 0.07 cm, 0.12 ± 0.15 cm, and 0.12 ± 0.12 cm in the lateral, longitudinal, and vertical directions, respectively; for FB, the errors were − 0.02 ± 0.12 cm, 0.08 ± 0.18 cm, and 0.14 ± 0.20 cm, respectively. For the target, DIBH plans were more sensitive to positioning errors; the mean deviations in D 95 for CTV were 39.78 Gy-40.17 Gy for DIBH and 38.46 Gy-40.52 Gy for FB, respectively. For the OARs, the mean deviations—V 10 , V 20 , and D mean to the heart; V 5 , V 20 , and D mean to the ipsilateral lung; and D mean to the breast—were lower for the FB plan compared with the DIBH plan. Conclusion SGRT can be an important tool for inter-fraction patient positioning and intra-fraction patient respiratory motion management in DIBH and FB breast cancer radiotherapy. The FB technology has greater possibility for the undercoverage of the target volume, while DIBH technology is more likely to result in increases in dose to organs at risk, especially the lung, heart, and breast. Furthermore, the tolerance of optical surface imaging systems could be reduced, indicating a potential method to reduce the dose delivery uncertainty caused by the patient’s respiratory motion. Surface guided radiotherapy Deep inspiration breath hold Volumetric modulated arc therapy Breast cancer Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Background Breast cancer is one of the most common cancers in women worldwide. This is also reflected in China, where it accounted for 16.72% (306000) of all cancers in women in 2016 [ 1 ]. However, breast cancer has a high 5-year overall survival rate of 90% due to advances in prevention, early diagnosis, and multidisciplinary therapy. Radiotherapy (RT) is an integral part of the multidisciplinary management of breast cancer [ 2 – 5 ]. For left-sided breast cancer, deep inspiration breath hold (DIBH) techniques with field-in-field (FiF) strategy have become a standard method in radiotherapy modality [6–8]. FiF strategy refers to two open opposing tangential radiation fields with several segments (usually two to four) with a multileaf collimator (MLC) instead of wedges for improving target dose homogenization. Many studies have been published in recent years to demonstrate the advantages of DIBH radiotherapy in breast cancer treatments, showing a reduced irradiation dose for nearby organs at risk (OAR) and maintaining a better target dose coverage, due to an increased distance between the target and the heart [9–10]. Moreover, volumetric modulated arc therapy (VMAT) resulted in even better target coverage, sparing OARs for complex targets, such as concave-shaped breasts and breast cancer with supraclavicular lymph nodes metastasis [ 11 , 12 ]. Patient positioning and respiratory movement are major concerns in dose delivery in FB and DIBH radiotherapy for breast cancer. This is because dose delivery deviation is mainly due to inaccuracy in patient positioning and patient respiratory movement throughout treatment, respectively. Regarding patient position, we can employ many additional imaging techniques, such as cone beam computed tomography (CBCT) and kilovoltage (kV) and megavoltage (MV) panel images to ensure accurate positioning. However, the disadvantages of such additional imaging are the associated extra radiation dose and the difficulty in monitoring patient respiratory motion for the whole treatment time. In recent years, optical surface imaging has provided the potential to monitor patient movement in real time during treatment and to help patients with pre-treatment positioning without the delivery of ionizing radiation [13,14]. Thus, surface-guided radiotherapy (SGRT) has been developed, which uses a 3-dimensional (3D) model of the skin surface for intrafraction patient positioning and monitoring for respiratory motion. The AlignRT system (Vision RT, London, UK) has been evaluated in this study. To our knowledge, studies comparing FB and DIBH in breast radiotherapy using the SGRT technique are rare. Therefore, in this paper, we aimed to evaluate the following: (1) the inter-fraction clinical performance of pre-treatment positioning of the AlignRT system as compared with the XVI system; (2) the intra-fraction respiratory motion data acquired by SGRT in breast patients with FB and DIBH; (3) the dosimetric effect of intra-fraction respiratory motion acquired by SGRT in breast patients with FB and DIBH; (4) the stability of FB and DIBH in breast radiotherapy of intra-fractional motion. Methods Patient selection and contouring Between February 2022 and October 2023, 17 patients with left-sided breast cancer treated with surface-guided DIBH and 20 patients with breast cancer treated by surface guided FB at the Department of Radiation Oncology, Sichuan Cancer Hospital, were recruited for the prospective study. This retrospective study was approved by the Ethics Committee of our hospital (Approval Number No. SCCHEC-02-2021-026). The mean age and median age were 57.6 ± 12.2 yrs and 55.2 yrs, respectively. Patient characteristics and radiotherapy parameters are summarized in Table 1 . Table 1 Patient characteristics and radiotherapy parameters of the study Parameters No. (%) Age (yrs.) Number of patients mean ± SD 57.6 ± 12.2 DIBH 17 (45.9%) median (range) 55.2 (50-68) FB 20 (54.1%) Tumors site Nodal status left 27 (73%) pN0 26 (70.3%) right 10 (27%) pN1 9 (24.3%) Tumor stage pN2 1 (2.7%) pT1 23 (62.2%) pN3 1 (2.7%) pT2 8 (21.6%) Fractionation pT3 5 (15.5%) Hypo-fractionated (2.67 Gy/15 F) 17 (45.9%) pT4 1 (2.7%) Hypo-fractionated with simultaneously integrated boost (2.67 Gy and 3.2 Gy/15 F) 20 (54.1%) The patients were immobilized with a WingStep (IT-V, Innsbruck, Austria) breast board in the supine position with their arms above their head. CT scans with a 3 mm slice thickness were acquired with a 16-slice Brilliance Big Bore CT (Philips Medical Systems, Cleveland, OH, USA). The CT scans were performed in free breathing (FB) and breath hold (BH) positions or with FB alone for their use in DIBH or FB treatment, respectively. After the CT scan, imaging datasets were imported to MIM Version 7.0.5 (MIM Software Inc.) for contouring. The CTVs and OARs (organ at risks) were delineated on each DIBH and FB scan by experienced radiation oncologists of the breast department. For the DIBH group, the clinical target volume (CTV DIBH ) encompassed the whole breast, excluding chest wall muscles, ribs, and pectoralis muscles, while for the FB group, CTV FB encompassed the whole breast and supraclavicular fossa region, and gross tumor volume (GTV) included the tumor bed, visible surgical clips, and anatomical distortion. The planning target volume (PTV FB and PTV DIBH ) was generated as an isotropic expansion of the CTV FB and CTV DIBH with a 3 mm margin in all directions, while PGTV was generated as an isotropic expansion of the GTV with a 5 mm margin in all directions. The OARs of this study were contoured on the CT image, which included the lung, heart, spinal cord, breast, liver, thyroid, esophagus, and trachea. Patients were treated either with hypo-fractionated therapy with simultaneously integrated boost (2.67 Gy for PTV FB and 3.2 Gy for PGTV in 15 fraction) for FB or hypo-fractionated therapy for DIBH (2.67 Gy for PTV DIBH in 15 fractions). SGRT workflow The AlignRT system (Vision RT, London, UK) employs a combination of light projectors, and the position of the patient is monitored with three cameras that generate a 3D map of the patient’s topography. Moreover, the system consists of software and a computer workstation, does not require the use of body film, and produces no irradiation during the imaging process. DIBH and FB patients were set up and monitored throughout treatment using AlignRT in real-time mode. In real-time mode, AlignRT displays three axis linear translations (vertical, lateral and longitudinal), the root mean square of the linear translations (RMS), and three axis rotations (yaw, pitch, and roll) (Fig. 1). The tolerance of linear translations and rotations is set to 3 mm and 3˚, respectively. For both DIBH and FB treatments, the SGRT workflow consists of initial setup in the AlignRT system, and preparation before DIBH and FB treatment and daily treatment (Fig. 2). The workflow of DIBH is the same as that published by our group in other, previous studies [15,16]. First, for the DIBH and FB treatments, import the FB body contour into the Align RT workstation, delineate the surface-monitoring region for the initial setup position, and name it ‘FB Setup-DIBH’ or ‘FB Setup-FB’, respectively. Furthermore, for the DIBH treatment, we also need to import the DIBH body contour and plan into the Align RT workstation, delineate the surface monitoring region, and name it ‘DIBH Setup’. Second, the AlignRT and CBCT are used for daily patient setup and to assess the agreement of AlignRT with CBCT. Move the couch to align the laser lights and the three patient tattoo marks, and then adjust the couch to roughly position the treatment isocenter over the ipsilateral breast. Open the patient's FB Setup monitoring in the Align RT workstation. Based on the system prompt for errors, manually adjust the rotational direction by ≤ 3°, and then perform linear translation by ≤ 3 mm. For the DIBH treatment, switch to the DIBH Setup monitoring in the Align RT workstation. Instruct the patient to perform DIBH. Based on system prompts for errors, perform fine adjustments to the couch value. Third, acquire the CBCT images and record the deviations from the XVI workstation. Then, shift the couch based on CBCT registration and capture the present surface image as a reference image. Finally, turn on the gating switch in the Align RT workstation and activate the Elekta Response controller to monitor patient respiratory motion during beam delivery. Fig. 3 shows the result of a typical breath-hold session with DIBH treatment and a free breath session with FB treatment, as tracked in the AlignRT system in a vertical direction and as printed from the system’s session reports, respectively. The shaded areas of Fig. 3 (A) indicate automatically gated beam hold when predetermined tolerance limits (± 3 mm) are exceeded. Treatment planning All clinical treatment plans were generated using Pinnacle TPS (version 9.10, Philips Radiation Oncology Systems, Fitchburg, WI, USA). Intensity modulation was performed using the direct machine parameter optimization (DMPO) algorithm. The collapsed cone (CC) algorithm was applied for final dose calculations, with a grid size of 3.0 mm. For the DIBH group, all plans used the tangential field-in-field (TFiF) technique, and treatments were performed with an Elekta Infinity linear accelerator (Elekta, Stockholm, Sweden) using 6 MV photons. Moreover, to be eligible for DIBH treatment, patients must be able to hold their breath for at least 25s and demonstrate a stable breath-hold position. The Infinity linear accelerator is equipped with a multileaf collimator, which has 40 leaf pairs of 0.5 cm thickness. The TFiF treatment plan consists of two opposing tangential fields with gantry angles between 300˚ and 315˚ for the medial beam and 120˚ and 135˚ for the lateral beam, with two or three sub-segments included. For the FB group, all plans had two arcs, with an angle ranging from 181˚ to 30˚ for the right-side breast cancer patients and from 330˚ to 179˚ for the left-side breast cancer patients, respectively. Eight setup variations were introduced for each reference DIBH and FB plan, shifting the isocenter from its reference position in the lateral, longitudinal, and vertical directions. The isocenter shifts in three directions with respect to the ±95% confidence interval of deviation distribution (mean±1.96*standard deviation) were acquired from the AlignRT system during beam-on time. A total of 296 perturbed plans (eight plans were generated per patient based on isocenter shifts values) were recalculated with these new isocenters and without changing any optimized parameters. Compared with the original plan, four groups of plans, DIBH min , DIBH max , FB min and FB max , were selected according to the maximum and minimum deviations of dosimetric parameters. The dose constraints for the PTV were 1) D 95 ≥100% of the prescribed dose, and 2) D 2 ≤110% of the prescribed dose. For the OAR, both the DIBH and FB plans met the dose volume limits, as detailed in Table 2 [17]. For each DIBH and FB patient, two plans were created based on the AlignRT system: 1) a triple VAMT arc using FFF beams (FB FFF ) with collimator 0° and couch 0°, and 2) a triple VAMT arc using FF beams (FB FF ) with collimator 0° and couch 0°. Table 2 Dose-volume constraints for OARs. OARs Dose volume parameters Spinal cord D max <40 Gy Ipsilateral lung D mean <15 Gy, V 20 <30%, V 5 <50% Contralateral lung V 5 <20% Heart (left-side breast cancer) D mean <15 Gy, V 5 <50% Heart (right-side breast cancer) D mean <15 Gy, V 5 <50% Liver V 5 <20% Thyroid D mean <30 Gy Evaluation of dosimetric data The dosimetric quality of the treatments was measured using a dose-volume histogram (DVH). For CTV, the target coverage (D 95 , D 98 , D 99 , D mean , D 50 , and D 2 ) and the conformity index (CI) were reported [18-20]. CI was defined as CI=(TV PV ) 2 /(TV×PV) (1) where PV is the volume covered by the prescription isodose. The CI values range between 0 and 1, and a CI close to 1 represents better conformity. Furthermore, dosimetric parameters were evaluated for the lung, heart, spinal cord, breast, liver, thyroid, esophagus, and trachea. The dose administered to the ipsilateral lung was evaluated using V 5 , V 10 , V 20 , and the D mean , and for the contralateral lung using V 5 , V 10 , and the D mean ; the D max of the spinal cord was also recorded. For the heart, the V 5 , V 10 , V 20 , and the D mean were scored; D max and D mean for the esophagus; D mean for the thyroid; D mean for the trachea; and V 5 and D mean for the liver. D x represented the dose (in Gy) received by x% of the volume, V y the volume (in percentage) receiving y Gy, D max the maximum dose, and D mean the mean dose. Datasets were statistically analyzed using SPSS 19.0 software (IBM, New York, USA). The dosimetric parameters of the PTV and OARs were compared using the Wilcoxon Cox test. A p -value <0.05 indicates statistically significant differences. Results Surface imaging system validation In summary, we analyzed 255 treatment fractions and 510 breath-hold sessions during beam-on time, which included 12750 points with a one-second interval for DIBH treatment, and 300 treatment fractions and 600 breath-free sessions during beam-on time, which included 69000 points with a one-second interval for FB treatment. The mean treatment session times were 50 s and 230 s for DIBH and FB treatment, respectively. The setup errors (lateral, longitudinal, and vertical) across all patients and sessions during the CBCT session from the AlignRT system and XVI system for DIBH and FB treatments are shown in Table 3. For both treatments, the setup errors were below 0.22 cm. There were significant differences found in the vertical direction for FB and DIBH treatments (p0.05). The setup deviations between AlignRT and XVI for DIBH treatment were 0.04 cm, 0.08 cm, and 0.02 cm in lat, lng, and vrt directions, respectively, and 0.06 cm, 0.08 cm, and 0.11 cm in lat, lng, and vrt directions for FB treatment, respectively. Table 3 The difference of setup errors (mean ± standard) between the AlignRT system and XVI system for the DIBH and FB treatment during a CBCT session. DIBH (cm) FB (cm) Parameters AlignRT XVI p AlignRT XVI p Lateral -0.05±0.07 -0.01±0.02 >0.05 -0.05±0.16 0.11±0.17 >0.05 Longitudinal 0.11±0.07 0.03±0.02 >0.05 0.11±0.18 -0.19±0.12 >0.05 Vertical 0.22±0.10 0.20±0.14 <0.05 0.10±0.17 0.21±0.13 <0.05 Table 4 shows the result of inter-fraction respiratory motion at beam-on time in terms of mean, standard deviation and ±95%-confidence interval (CI) for DIBH and FB treatments, respectively. Overall, the mean changes for the maximum magnitude of the respiratory motion on the vertical axis were 0.12 ± 0.12 (±95%-confidence interval: [-0.12-0.36] cm) and 0.14 ± 0.20 (±95%-confidence interval: [-0.25-0.53] cm) cm for DIBH and FB treatment, respectively. Along the lateral and longitudinal axes, changes were quite similar: -0.06±0.07, 0.12±0.15, -0.02±0.06, and 0.08±0.08 mm for DIBH and FB treatments, respectively. Figure 4 shows histograms representing the differences between conventional patient positioning and the surface-based alignments for DIBH and FB treatment. More than 61.67% and 78.14% of the deviations were smaller than 2 mm in the lateral direction for DIBH and FB, respectively; more than 58.48% and 68.72% of the deviations were smaller than 2 mm in the longitudinal direction for DIBH and FB, respectively; and more than 63.76% and 75.35% of the deviations were smaller than 2 mm in the vertical direction for DIBH and FB, respectively. Table 4 The inter-fraction respiratory motion data acquiring by SGRT for FB and DIBH treatment during a beam on time. Treatment Beam on time Lateral (cm) Longitudinal (cm) Vertical (cm) Mean ± SD CI-95% CI+95% Mean ± SD CI-95% CI+95% Mean ± SD CI-95% CI+95% DIBH -0.06±0.07 -0.20 0.07 0.12±0.15 -0.17 0.41 0.12±0.12 -0.12 0.36 FB -0.02±0.12 -0.26 0.22 0.08±0.18 -0.27 0.43 0.14±0.20 -0.25 0.53 Target doses The CTV dosimetric parameters (mean and standard) obtained for the DIBH and FB treatments are shown in Table 5 and Figure 5. The target coverage of the original plans was clinically acceptable for both techniques, with D 95 values of 40.1±1.36 Gy and 40.52±0.19 Gy for DIBH and VAMT treatments, respectively. For DIBH treatment, the dosimetric parameter differences in the DIBH org plan compared with DIBH min and DIBH max plans were statistically significant (p<0.05). The mean absolute differences (DIBH max -DIBH min ) ΔD 95 , ΔD 98 , ΔD 99 , ΔD mean , ΔD 2 , ΔD max , ΔD 50 , and ΔCI were 0.39 Gy, 0.58 Gy, 1.0 Gy, 0.56 Gy, 1.33 Gy, 1.67 Gy, 0.77 Gy, and 0.12 Gy, respectively. For VAMT treatment, there was no significant difference in the D 98 and D 99 of the CTV between FB org and FB max plans (p>0.05), and the differences in other parameters were statistically significant (p<0.05). The mean absolute differences (FB max -FB min ) ΔD 95 , ΔD 98 , ΔD 99 , ΔD mean , ΔD 2 , ΔD max , ΔD 50 , and ΔCI were 2.3 Gy, 3.96 Gy, 4.41 Gy, 1.27 Gy, 2.12 Gy, 3.21 Gy, 1.11 Gy, and 0.07 Gy, respectively. The mean absolute differences in CTV between DIBH min and DIBH max and FB min and FB max are shown in Figure 6a. In Figure 6a, for the CTV, the absolute differences in the dosimetric parameters of DIBH treatment were lower than the FB treatment. Table 5 Mean value and range of CTV dosimetric parameters absolute between the original and perturbed DIBH and FB treatments. Volume Parameters DIBH FB DIBH org DIBH min DIBH max p value FB org FB min FB max p value p1 p2 p1 p2 CTV D 95 (Gy) 40.10±1.36 39.78±0.86 40.17±0.79 <0.05 <0.05 40.52±0.19 38.46±1.76 40.76±0.31 <0.05 <0.05 D 98 (Gy) 39.10±1.06 38.59±1.36 39.17±1.09 <0.05 <0.05 40.09±0.22 36.54±2.79 40.05±0.48 <0.05 0.795 D 99 (Gy) 38.37±1.26 37.50±2.03 38.50±1.28 <0.05 0.097 39.79±0.30 35.13±3.28 39.54±0.59 <0.05 0.173 D mean (Gy) 42.42±0.14 42.26±0.19 42.82±0.31 <0.05 <0.05 43.44±1.0 42.75±1.01 44.02±1.23 <0.05 <0.05 D 2 (Gy) 43.69±0.15 43.98±0.40 45.31±0.72 <0.05 <0.05 49.27±2.68 48.67±2.52 50.79±3.17 <0.05 <0.05 D max (Gy) 44.11±0.18 44.52±0.55 46.19±0.57 <0.05 <0.05 50.54±2.77 49.90±2.66 53.11±3.67 <0.05 <0.05 D 50 (Gy) 42.75±0.14 42.32±0.14 43.09±0.30 <0.05 <0.05 42.43±0.86 41.95±0.95 43.06±1.07 <0.05 <0.05 CI 0.67±0.07 0.49±0.09 0.61±0.06 <0.05 <0.05 0.67±0.12 0.65±0.08 0.72±0.09 <0.05 <0.05 OARs doses OARs’ DVH dosimetric parameters (mean and range values), obtained for the original (DIBH org and FB org ) and perturbed (DIBH min , DIBH max , FB min and FB max ) DIBH and FB treatments, are shown in Table 6 and Figure 6. The mean absolute differences (DIBH max -DIBH min ) ΔV 5 , ΔV 10 , ΔV 20 and ΔD mean of the heart; ΔD max of the spinal cord; ΔV 5 , ΔV 10 , ΔV 20 and ΔD mean of the ipsilateral lung; ΔV 5 , ΔV 10 and ΔD mean of the contralateral lung; ΔD mean of the breast; ΔD mean of the thyroid; ΔD mean of the trachea; and ΔD max and ΔD mean of the esophagus were 3.03 %, 8.64 %, 6.63%, 2.99 Gy, 0.1 Gy, 11.98%, 11.64%, 11.08 %, 4.23 Gy, 0.3 %, 0.13 %, 0.16 Gy, 2.02 Gy, 0.19 Gy, 0.23 Gy, 0.34 Gy, 0.18 Gy, 0.12 % and 0.13 Gy, respectively. The mean absolute differences (FB max -FB min ) ΔV 5 , ΔV 10 , ΔV 20 and ΔD mean of the heart; ΔD max of the spinal cord; ΔV 5 , ΔV 10 , ΔV 20 and ΔD mean of the ipsilateral lung; ΔV 5 , ΔV 10 and ΔD mean of the contralateral lung; ΔD mean of the breast; ΔD mean of the thyroid; ΔD mean of the trachea; and ΔD max and ΔD mean of the esophagus were 11.65%, 5.39%, 1.52%, 1.48 Gy, 0.72 Gy, 10.69 %, 11.96%, 10.14 %, 3.45 Gy, 4.76% 1.39%, 0.4 Gy, 0.52 Gy, 0.52 Gy, 0.91 Gy, 1.71 Gy, 0.42 Gy, 5.38% and 0.94 Gy, respectively. The mean absolute differences in OARs between DIBH min and DIBH max and FB min and FB max are shown in Figure 7b. In Figure 6b, compared with DIBH treatment, the FB treatment provided a lower mean absolute difference V 10 , V 20 , and D mean to the heart; V 5 , V 20 , and D mean to the ipsilateral lung; and D mean to the breast. Table 6 Mean value and range of OARs dosimetric parameters absolute between the original and perturbed DIBH and FB treatments. Volume Parameters DIBH FB DIBH org DIBH min DIBH max p value FB org FB min FB max p value p1 p2 p1 p2 Heart V 5 (%) 4.86±2.92 1.83±1.77 4.86±2.92 <0.05 <0.05 11.07±9.40 7.18±8.85 18.83±11.22 <0.05 <0.05 V 10 (%) 2.75±1.94 0.71±1.05 9.35±5.93 <0.05 <0.05 2.59±3.54 1.12±1.69 6.51±7.12 0.051 <0.05 V 20 (%) 1.56±1.29 0.30±0.63 6.93±4.95 <0.05 <0.05 0.31±0.59 0.03±0.07 1.55±2.60 0.144 0.104 D mean (Gy) 1.83±0.68 1.13±0.41 4.12±2.01 <0.05 <0.05 2.63±0.91 2.17±0.07 3.65±1.55 <0.05 <0.05 Spinal cord D max (Gy) 0.24±0.07 0.20±0.06 0.30±0.06 <0.05 <0.05 2.82±1.84 2.57±1.70 3.29±2.03 <0.05 <0.05 Ipsilateral lung V 5 (%) 23.50±2.76 18.61±2.55 30.59±3.89 <0.05 <0.05 33.46±5.66 28.72±5.16 39.41±6.37 <0.05 <0.05 V 10 (%) 17.47±2.32 12.84±2.12 24.48±3.62 <0.05 <0.05 19.40±5.77 14.14±4.64 26.10±7.02 <0.05 <0.05 V 20 (%) 12.84±1.91 8.55±1.82 19.63±3.29 <0.05 <0.05 6.97±4.28 3.0±2.62 13.14±6.68 <0.05 <0.05 D mean (Gy) 6.07±0.71 4.48±0.69 8.71±1.26 <0.05 <0.05 6.08±1.53 4.80±1.08 8.25±2.26 <0.05 <0.05 Contralateral lung V 5 (%) 0.01±0.02 0±0 0.30±0.69 0.347 0.229 12.37±11.66 10.12±10.71 14.88±12.24 <0.05 <0.05 V 10 (%) 0±0 0±0 0.13±0.31 0.145 0.260 1.82±2.66 1.19±1.90 2.58±3.40 0.085 <0.05 D mean (Gy) 0.22±0.05 0.18±0.03 0.34±0.17 <0.05 <0.05 2.28±0.96 2.11±0.93 2.51±1.01 <0.05 <0.05 Breast D mean (Gy) 1.19±2.06 0.61±0.64 2.63±4.79 0.252 0.153 3.10±1.22 2.91±1.18 3.43±1.33 <0.05 <0.05 Thyroid D mean (Gy) 0.29±0.13 0.22±0.11 0.41±0.20 <0.05 <0.05 0.83±0.31 0.63±0.19 1.15±0.54 <0.05 <0.05 Trachea D mean (Gy) 0.37±0.06 0.29±0.06 0.52±0.10 <0.05 <0.05 2.22±1.51 1.79±1.26 2.70±1.79 <0.05 <0.05 Esophagus D max (Gy) 0.54±0.09 0.44±0.05 0.78±0.20 <0.05 <0.05 5.38±2.84 4.68±2.58 6.39±3.17 <0.05 <0.05 D mean (Gy) 0.44±0.09 0.26±0.05 0.44±0.09 <0.05 <0.05 1.63±0.89 1.44±0.77 1.86±1.0 <0.05 <0.05 Liver V 5 (%) 0±0 0±0 0.12±0.23 0.231 0.160 7.30±5.33 5.17±3.95 10.55±7.30 <0.05 <0.05 D mean (Gy) 0.17±0.05 0.13±0.04 0.26±0.10 <0.05 <0.05 1.65±0.90 1.30±0.68 2.24±1.29 <0.05 <0.05 Discussion In recent years, radiotherapy techniques such as FB and DIBH have been used widely in the radiotherapy of breast cancer. The present study addresses the topic of FB and DIBH stability and reproducibility during surface-guided breast radiotherapy. Surface imaging can be used to monitor the chest wall position during DIBH and the FB. We report on intra-breath-hold and intra-free-breath stability and inter-fraction reproducibility during DIBH and FB radiotherapy in a breast cancer patient study (17 patients with 12750 points for DIBH and 20 patients with 69000 points for VMA) and using an Align RT system. DIBH and FB techniques have different dosimetry advantages in the radiotherapy of breast cancer, respectively. However, in addition to dosimetry considerations, patient positioning and respiratory movement are major concerns for dose delivery in FB and DIBH radiotherapy for breast cancer. This requires patient positioning monitoring be maintained as accurately as possible during treatment to ensure that the dose is delivered as intended. Shah et al. analyzed 50 patients undergoing radiation therapy for whole breast; these patients were aligned daily using optical surface imaging, and shifts from skin marks were recorded, in comparison with MV port films [ 21 ]. Reitz et al. evaluated intra-breath-hold stability and inter-fraction breath-hold reproducibility in clinical practice [ 22 ]. Compared with general images from CBCT, SGRT (non-invasive and non-radiative) uses optical surface imaging to verify the position. Several studies have evaluated the setup accuracy of SGRT systems compared to CBCT [ 23 – 25 ]. In our study, CBCT was used to verify AlignRT system corrections, showing the stability gained when using SGRT for intra-fraction patient setup, where the setup error is similar to CBCT. Average setup differences between both AlignRT and CBCT were below 0.08 cm for DIBH treatment and below 0.11 cm for FB treatment, in three directions. This result is in agreement with previous studies [ 25 , 26 ]. Alderliesten et al [ 25 ] also compared the AlignRT system to CBCT imaging setup errors for DIBH radiotherapy, and showed similar results. Batin et al. [ 26 ] demonstrated that positioning with AlignRT after laser alignment is more accurate than when only the laser is used. In Table 3 , it can be observed that the setup errors from AlignRT were slightly larger than with the CBCT. This is because for the CBCT, the setup error was based on the target volume, but the AlignRT was based on the patient’s surface imaging. In addition, due to the different ROI position, AlignRT mainly looks at the ventral side of the breast, which can differ in shape during an optical imaging acquisition session. Thus, AlignRT has reliable patient positioning stability similar to CBCT and the potential to replace CBCT for positioning in breast cancer patients using FB and DIBH. At present, analyses of dosimetry between DIBH and FB have been reported in many studies [ 27 – 29 ]. In addition to dosimetry comparisons, the impact of patient respiration on both techniques needs to be evaluated. Patient respiration can lead to an increase in dose delivery uncertainty, prompting the monitoring of treatment delivery to ensure that the target and OAR-delivered dose correspond to those planned. However, most prior studies did not report dosimetric deviation due to patient respiration during beam-on duration, but mainly focused on the three directions of motion of the patient [ 22 , 23 , 30 ]. Zhao et al. [ 15 ] compared the impact of positioning errors in FB and tangential field-in-field (TFiF) plans for breast treatments, but the positioning errors in the three directions were artificially set to 3, 5, and 10 mm, and not taken from the surface-guided system. In addition to the advantages provided with SGRT for setup positioning, the main advantage in the present study is the opportunity for real-time monitoring. In this study, firstly, patient respiratory data were acquired from AlignRT for DIBH and FB treatments; secondly, perturbations were introduced to the plans. Intra-DIBH and intra-FB stability were both smallest in the vertical direction during beam-on time, as shown in Table 4 . This may be due to patient respiration factors during beam-on time. The deviation values in the vertical direction averaged over all patients were 0.12 ± 0.12 cm for DIBH and 0.14 ± 0.20 cm for FB, respectively. The average value and standard deviation showed that the respiratory motion amplitude of FB technology is greater than DIBH. The reason for this situation is that patients use FB technology in a state of free breathing, and inhalation and exhalation have a positive and negative relationship in the AlignRT system, which leads to a greater average value. Our surface-based alignments specifically showed that across all patients, skin-mark alignments were poorer in the three directions (especially the deviation within the range from − 2 to 2 mm) for DIBH treatment in comparison with the FB treatment (Fig. 4 ). This result indicates that the stability of the FB treatment is better than the DIBH treatment of inter-fractional motion. This is because DIBH treatment has higher requirements for patients; patients must be able to hold their breath for at least 25 s and to replicate the breath retention setting five times in succession. One potential solution could involve increasing patient’s breath-holding training. When perturbations were introduced to DIBH and FB plans, however, DIBH techniques guaranteed an accurate target coverage with deviations in the target DVH dosimetric, whereas FB plans seemed more sensitive to positioning errors, with mean deviations of 2.3 Gy and 3.96 Gy for D 95 and D 98 , respectively. In Table 5 and Fig. 6 (A), it is possible to observe that respiratory movement has a dosimetric impact on CTV that is larger for FB plans than for DIBH plans. Zhao et al. [ 15 ] also found such dosimetric effects. For breast cancer radiotherapy, dose sparing of the ipsilateral lung, contralateral breast, and heart are particularly important. For the OARs, DIBH plans appeared to be more sensitive to the positioning errors’ mean absolute difference (Plan max -Plan min ) for V 10 , V 20 , and D mean to the heart, V 5 , V 20 , and D mean to the ipsilateral lung, and D mean to the breast. In addition, the well-known second cancer risk for contralateral breast and lung forces us to monitor treatment delivery to ensure that the OAR-delivered dose corresponds to the planned one [ 32 ]. One possible solution is to increase the threshold in the optical surface imaging system, with beam delivery interruption if patients’ positions exceed their tolerance limits. One limitation of this study is that the tolerance of linear translations and rotations are set to 3 mm and 3˚ in the AlignRT system. Xiao et al. [ 31 ] reported different values of variabilities (translation 1 mm and rotation 1˚), which resulted in small dosimetric consequences. Thus, a lower tolerance could assure DIBH and FB with good stability and low intra-fraction and inter-fraction variability, contributing to smaller deviations in dosimetric delivery. The three axis rotations from AlignRT were not discussed. Wiant et al. [ 32 ] showed that the mean rotations were all < 0.1˚ for thirty free-breathing breast patients. This indicates that rotation deviations might negligible in dosimetric delivery. Conclusion To conclude, due to the large amount of data analyzed, the optical real-time surface imaging system in the present study was demonstrated to be an important tool for inter-fraction patient positioning and intra-fraction patient respiratory motion management in DIBH and FB breast cancer radiotherapy. Regarding the reproducibility of DIBH and FB, the setup deviations between AlignRT and CBCT were both < 0.12 cm. As a measure of DIBH and FB stability, the mean deviations were both < 0.2 cm. The FB technology has greater possibility for the undercoverage of the target volume, while DIBH technology is more likely to result in increases in dose to organs at risk, especially the lung, heart, and breast. In addition, the tolerance of the optical surface imaging system could be reduced, and could then become a potential method for reducing the dose delivery uncertainty caused by patient respiratory motions. Declarations Acknowledgements None. Conflict of interest statement There is no conflict of interest to declare. Author contributions Design of the research: BT, JXW. Treatment plans: FW, FY. Statistical Analysis: OL, JL, KY, LPX. Manuscript preparation: FY, JXW. Manuscript writing: JXW. Manuscript final revision: BT, XLW. All authors contributed to the article and approved the submitted version. Funding This study was supported by Sichuan Natural Science Foundation Program (No. 2024NSFSC1878) and Sichuan Cancer Hospital Youth Project (No. YB2023025, No. YB2021032). Availability of data and materials The data are fully available without restriction in a public repository (Dryad). The reference treatment plans and corresponding perturbed plans were archived in the Informatic System of Sichuan Cancer Hospital. Declarations Ethics approval and consent to participate This retrospective study was approved by the Ethics Committee of our hospital (Approval Number No. SCCHEC-02-2021-026). Consent for publication Not applicable. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4962651","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":358029554,"identity":"2f9417af-e265-49a6-a627-de222aff6fa9","order_by":0,"name":"Junxiang Wu","email":"","orcid":"","institution":"Sichuan Cancer Hospital \u0026 Institute, University of Electronic Science and Technology of China","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Junxiang","middleName":"","lastName":"Wu","suffix":""},{"id":358029558,"identity":"f10cc571-7c26-4360-85b9-9cf2a1e35a26","order_by":1,"name":"Feng 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04:50:55","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":137073,"visible":true,"origin":"","legend":"\u003cp\u003eThe workflow of DIBH and FB with SGRT\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-4962651/v1/010a6c304eda5d24d03eebc3.png"},{"id":66840621,"identity":"ea6bae3c-da93-464f-bc51-d9bb61b3efd1","added_by":"auto","created_at":"2024-10-17 04:58:55","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":958094,"visible":true,"origin":"","legend":"\u003cp\u003eThe result of typical session as tracked in the AlignRT system in vertical\u003cstrong\u003e \u003c/strong\u003edirection: (A) DIBH treatment; (B) FB treatment;\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-4962651/v1/4c10a99be78ecae14ca0a57e.png"},{"id":66839905,"identity":"fa43309c-cdc4-485d-b288-620c6627b108","added_by":"auto","created_at":"2024-10-17 04:50:55","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":880770,"visible":true,"origin":"","legend":"\u003cp\u003eThe percent of fractions binned by deviation of three directions for all patients and all fractions: (A) lateral direction for DIBH; (B) lateral direction for FB; (C) longitudinal direction for DIB; (D) longitudinal direction for FB; (E) vertical direction for DIBH; (F) vertical direction for FB.\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-4962651/v1/598e29fc2de7487f52b4ecd0.png"},{"id":66839902,"identity":"935787e0-e90a-4a9a-8ec0-b75c8d86b8a8","added_by":"auto","created_at":"2024-10-17 04:50:55","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":983203,"visible":true,"origin":"","legend":"\u003cp\u003eThe original and eight perturbed plans dose volume histograms of CTV and GTV from the two treatments: (A) CTV of DIBH treatment; (B) CTV and GTV of FB treatment\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-4962651/v1/c77e2a28705acdb585339044.png"},{"id":66839907,"identity":"8afc4485-6ce1-4cc1-b89c-152ba382a5a4","added_by":"auto","created_at":"2024-10-17 04:50:55","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":1419039,"visible":true,"origin":"","legend":"\u003cp\u003eThe original and eight perturbed plans dose volume histograms of ipsilateral lung and heart from the two treatments: (A) heart of DIBH treatment; (B) heart of FB treatment;(C) ipsilateral lung of DIBH treatment; (D) ipsilateral lung of FB treatment\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-4962651/v1/8f72cf83600f579f1fc4d34f.png"},{"id":66840620,"identity":"bf051552-1903-4b79-bd87-f49f42741ce2","added_by":"auto","created_at":"2024-10-17 04:58:55","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":529677,"visible":true,"origin":"","legend":"\u003cp\u003eMean value and range of CTV and OARs dosimetric parameters absolute difference between the original and perturbed DIBH and FB treatments: (A) CTV; (B) OARs\u003c/p\u003e\n\u003cp\u003eThe units of V\u003csub\u003ex\u003c/sub\u003e is %, D\u003csub\u003ey\u003c/sub\u003e is Gy\u003c/p\u003e","description":"","filename":"floatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-4962651/v1/69d3311bd1607c870f4d78e8.png"},{"id":69285128,"identity":"32b161ff-284c-4fe5-87c6-4bff8444a40f","added_by":"auto","created_at":"2024-11-18 19:24:08","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":6714782,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4962651/v1/5d4bf8bd-def4-430d-ba2c-6958a397e8cd.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Reproducibility and stability of deep inspiration breath hold and free breath in breast radiotherapy based on real-time 3-dimensional optical surface imaging system","fulltext":[{"header":"Background","content":"\u003cp\u003eBreast cancer is one of the most common cancers in women worldwide. This is also reflected in China, where it accounted for 16.72% (306000) of all cancers in women in 2016 [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. However, breast cancer has a high 5-year overall survival rate of 90% due to advances in prevention, early diagnosis, and multidisciplinary therapy. Radiotherapy (RT) is an integral part of the multidisciplinary management of breast cancer [\u003cspan additionalcitationids=\"CR3 CR4\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eFor left-sided breast cancer, deep inspiration breath hold (DIBH) techniques with field-in-field (FiF) strategy have become a standard method in radiotherapy modality [6\u0026ndash;8]. FiF strategy refers to two open opposing tangential radiation fields with several segments (usually two to four) with a multileaf collimator (MLC) instead of wedges for improving target dose homogenization. Many studies have been published in recent years to demonstrate the advantages of DIBH radiotherapy in breast cancer treatments, showing a reduced irradiation dose for nearby organs at risk (OAR) and maintaining a better target dose coverage, due to an increased distance between the target and the heart [9\u0026ndash;10]. Moreover, volumetric modulated arc therapy (VMAT) resulted in even better target coverage, sparing OARs for complex targets, such as concave-shaped breasts and breast cancer with supraclavicular lymph nodes metastasis [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e \u003cp\u003ePatient positioning and respiratory movement are major concerns in dose delivery in FB and DIBH radiotherapy for breast cancer. This is because dose delivery deviation is mainly due to inaccuracy in patient positioning and patient respiratory movement throughout treatment, respectively. Regarding patient position, we can employ many additional imaging techniques, such as cone beam computed tomography (CBCT) and kilovoltage (kV) and megavoltage (MV) panel images to ensure accurate positioning. However, the disadvantages of such additional imaging are the associated extra radiation dose and the difficulty in monitoring patient respiratory motion for the whole treatment time. In recent years, optical surface imaging has provided the potential to monitor patient movement in real time during treatment and to help patients with pre-treatment positioning without the delivery of ionizing radiation [13,14]. Thus, surface-guided radiotherapy (SGRT) has been developed, which uses a 3-dimensional (3D) model of the skin surface for intrafraction patient positioning and monitoring for respiratory motion. The AlignRT system (Vision RT, London, UK) has been evaluated in this study.\u003c/p\u003e \u003cp\u003eTo our knowledge, studies comparing FB and DIBH in breast radiotherapy using the SGRT technique are rare. Therefore, in this paper, we aimed to evaluate the following: (1) the inter-fraction clinical performance of pre-treatment positioning of the AlignRT system as compared with the XVI system; (2) the intra-fraction respiratory motion data acquired by SGRT in breast patients with FB and DIBH; (3) the dosimetric effect of intra-fraction respiratory motion acquired by SGRT in breast patients with FB and DIBH; (4) the stability of FB and DIBH in breast radiotherapy of intra-fractional motion.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cstrong\u003ePatient selection and contouring\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBetween February 2022 and October 2023, 17 patients with left-sided breast cancer treated with surface-guided DIBH and 20 patients with breast cancer treated by surface guided FB at the Department of Radiation Oncology, Sichuan Cancer Hospital, were recruited for the prospective study. This retrospective study was approved by the Ethics Committee of our hospital (Approval Number No. SCCHEC-02-2021-026). The mean age and median age were 57.6 \u0026plusmn; 12.2 yrs and 55.2 yrs, respectively. Patient characteristics and radiotherapy parameters are summarized in \u003cstrong\u003eTable 1\u003c/strong\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1\u003c/strong\u003e Patient characteristics and radiotherapy parameters of the study\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"540\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameters\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo. (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003eAge (yrs.)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003eNumber of patients\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003emean \u0026plusmn; SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e57.6\u0026nbsp;\u0026plusmn; 12.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003eDIBH\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e17 (45.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003emedian (range)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e55.2 (50-68)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003eFB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e20 (54.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003eTumors site\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003eNodal status\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003eleft\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e27 (73%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003epN0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e26 (70.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003eright\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e10 (27%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003epN1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e9 (24.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003eTumor stage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003epN2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e1 (2.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003epT1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e23 (62.2%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003epN3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e1 (2.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003epT2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e8 (21.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003eFractionation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003epT3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e5 (15.5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003eHypo-fractionated\u003c/p\u003e\n \u003cp\u003e(2.67 Gy/15 F)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e17 (45.9%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23.1054%;\"\u003e\n \u003cp\u003epT4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 3.51201%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.7116%;\"\u003e\n \u003cp\u003e1 (2.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.1756%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 35.4898%;\"\u003e\n \u003cp\u003eHypo-fractionated with simultaneously integrated boost\u003c/p\u003e\n \u003cp\u003e(2.67 Gy and 3.2 Gy/15 F)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 2.95749%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0481%;\"\u003e\n \u003cp\u003e20 (54.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eThe patients were immobilized with a WingStep (IT-V,\u0026nbsp;Innsbruck, Austria) breast board in the supine position\u0026nbsp;with their arms above their head. CT scans with a 3 mm slice thickness were acquired with a 16-slice Brilliance Big Bore CT (Philips Medical Systems, Cleveland, OH, USA). The CT scans were performed in free breathing (FB) and breath hold (BH) positions or with FB alone for their use in DIBH or FB treatment, respectively. After the CT scan, imaging datasets were imported to MIM Version 7.0.5 (MIM Software Inc.) for contouring. The CTVs and OARs (organ at risks) were delineated on each DIBH and FB scan by experienced radiation oncologists of the breast department. For the DIBH group, the clinical target volume (CTV\u003csub\u003eDIBH\u003c/sub\u003e) encompassed the whole breast, excluding chest wall muscles, ribs, and pectoralis muscles, while for the FB group, CTV\u003csub\u003eFB\u003c/sub\u003e encompassed the whole breast and supraclavicular fossa region, and gross tumor volume (GTV) included the tumor bed, visible surgical clips, and anatomical distortion. The planning target volume (PTV\u003csub\u003eFB\u003c/sub\u003e and PTV\u003csub\u003eDIBH\u003c/sub\u003e) was generated as an isotropic expansion of the CTV\u003csub\u003eFB\u003c/sub\u003e and CTV\u003csub\u003eDIBH\u003c/sub\u003e with a 3 mm margin in all directions, while PGTV was generated as an isotropic expansion of the GTV with a 5 mm margin in all directions. The OARs of this study were contoured on the CT image, which included the lung, heart, spinal cord, breast, liver, thyroid, esophagus, and trachea. Patients were treated either with hypo-fractionated therapy with simultaneously integrated boost (2.67 Gy for PTV\u003csub\u003eFB\u003c/sub\u003e and 3.2 Gy for PGTV in 15 fraction) for FB or hypo-fractionated therapy for DIBH (2.67 Gy for PTV\u003csub\u003eDIBH\u003c/sub\u003e in 15 fractions).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSGRT workflow\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe AlignRT system (Vision RT, London, UK) employs a combination of light projectors, and the position of the patient is monitored with three cameras that generate a 3D map of the patient\u0026rsquo;s topography. Moreover, the system consists of software and a computer workstation, does not require the use of body film, and produces no irradiation during the imaging process. DIBH and FB patients were set up and monitored throughout treatment using AlignRT in real-time mode. In real-time mode, AlignRT displays three axis linear translations (vertical, lateral and longitudinal), the root mean square of the linear translations (RMS), and three axis rotations (yaw, pitch, and roll) (Fig. 1). The tolerance of linear translations and rotations is set to 3 mm and 3˚, respectively. \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFor both DIBH and FB treatments, the SGRT workflow consists of initial setup in the AlignRT system, and preparation before DIBH and FB treatment and daily treatment (Fig. 2). The workflow of DIBH is the same as that published by our group in other, previous studies [15,16]. First, for the DIBH and FB treatments, import the FB body contour into the Align RT workstation, delineate the surface-monitoring region for the initial setup position, and name it \u0026lsquo;FB Setup-DIBH\u0026rsquo; or \u0026lsquo;FB Setup-FB\u0026rsquo;, respectively. Furthermore, for the DIBH treatment, we also need to import the DIBH body contour and plan into the Align RT workstation, delineate the surface monitoring region, and name it \u0026lsquo;DIBH Setup\u0026rsquo;. Second, the AlignRT and CBCT are used for daily patient setup and to assess the agreement of AlignRT with CBCT. Move the couch to align the laser lights and the three patient tattoo marks, and then adjust the couch to roughly position the treatment isocenter over the ipsilateral breast. Open the patient\u0026apos;s FB Setup monitoring in the Align RT workstation. Based on the system prompt for errors, manually adjust the rotational direction by \u0026le; 3\u0026deg;, and then perform linear translation by \u0026le; 3 mm. For the DIBH treatment, switch to the DIBH Setup monitoring in the Align RT workstation. Instruct the patient to perform DIBH. Based on system prompts for errors, perform fine adjustments to the couch value. Third, acquire the CBCT images and record the deviations from the XVI workstation. Then, shift the couch based on CBCT registration and capture the present surface image as a reference image. Finally, turn on the gating switch in the Align RT workstation and activate the Elekta Response controller to monitor patient respiratory motion during beam delivery.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFig. 3 shows the result of a typical breath-hold session with DIBH treatment and a free breath session with FB treatment, as tracked in the AlignRT system in a vertical\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003edirection and as printed from the system\u0026rsquo;s session reports, respectively. The shaded areas of Fig. 3 (A) indicate automatically gated beam hold when predetermined tolerance limits (\u0026plusmn; 3 mm) are exceeded.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTreatment planning\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll clinical treatment plans were generated using Pinnacle TPS (version 9.10, Philips Radiation Oncology Systems, Fitchburg, WI, USA). Intensity modulation was performed using the direct machine parameter optimization (DMPO) algorithm. The collapsed cone (CC) algorithm was applied for final dose calculations, with a grid size of 3.0 mm. For the DIBH group, all plans used the tangential field-in-field (TFiF) technique, and treatments were performed with an Elekta Infinity linear accelerator (Elekta, Stockholm, Sweden) using 6 MV photons. Moreover, to be eligible for DIBH treatment, patients must be able to hold their breath for at least 25s and demonstrate a stable breath-hold position. The Infinity linear accelerator is equipped with a multileaf collimator, which has 40 leaf pairs of 0.5 cm thickness. The TFiF treatment plan consists of two opposing tangential fields with gantry angles between 300˚\u0026nbsp;and 315˚\u0026nbsp;for the medial beam and 120˚\u0026nbsp;and 135˚\u0026nbsp;for the lateral beam, with two or three sub-segments included. For the FB group, all plans had two arcs, with an angle ranging from 181˚ to 30˚ for the right-side breast cancer patients and\u0026nbsp;from 330˚ to 179˚ for the left-side breast cancer patients, respectively. Eight setup variations were introduced for each reference DIBH and FB plan, shifting the isocenter from its reference position in\u0026nbsp;the lateral, longitudinal, and vertical directions. The isocenter shifts in three directions with respect to the\u0026nbsp;\u0026plusmn;95% confidence interval of deviation distribution (mean\u0026plusmn;1.96*standard deviation) were acquired from the AlignRT system during beam-on time.\u0026nbsp;A total of 296 perturbed plans (eight plans were generated per patient based on isocenter shifts values) were recalculated with these new isocenters and without changing any optimized parameters. Compared with the original plan, four groups of plans, DIBH\u003csub\u003emin\u003c/sub\u003e, DIBH\u003csub\u003emax\u003c/sub\u003e, FB\u003csub\u003emin\u003c/sub\u003e and FB\u003csub\u003emax\u003c/sub\u003e, were selected according to the maximum and minimum deviations of dosimetric parameters.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe dose constraints for the PTV were 1) D\u003csub\u003e95\u003c/sub\u003e\u0026ge;100% of the prescribed dose, and 2) D\u003csub\u003e2\u003c/sub\u003e\u0026le;110% of the prescribed dose. For the OAR, both the DIBH and FB plans met the dose volume limits, as detailed in \u003cstrong\u003eTable 2\u0026nbsp;\u003c/strong\u003e[17]. For each DIBH and FB patient, two plans were created based on the AlignRT system: 1) a triple VAMT arc using FFF beams (FB\u003csub\u003eFFF\u003c/sub\u003e) with collimator 0\u0026deg; and couch\u0026nbsp;0\u0026deg;, and 2) a triple VAMT arc using FF beams (FB\u003csub\u003eFF\u003c/sub\u003e) with collimator 0\u0026deg; and couch\u0026nbsp;0\u0026deg;.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2\u003c/strong\u003e Dose-volume constraints for OARs.\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 40.1302%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOARs\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59.8698%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDose volume parameters\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 40.1302%;\"\u003e\n \u003cp\u003eSpinal cord\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59.8698%;\"\u003e\n \u003cp\u003eD\u003csub\u003emax\u003c/sub\u003e\u0026lt;40 Gy\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 40.1302%;\"\u003e\n \u003cp\u003eIpsilateral lung\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59.8698%;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e\u0026lt;15 Gy, V\u003csub\u003e20\u003c/sub\u003e\u0026lt;30%, V\u003csub\u003e5\u003c/sub\u003e\u0026lt;50%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 40.1302%;\"\u003e\n \u003cp\u003eContralateral lung\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59.8698%;\"\u003e\n \u003cp\u003eV\u003csub\u003e5\u003c/sub\u003e\u0026lt;20%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 40.1302%;\"\u003e\n \u003cp\u003eHeart (left-side breast cancer)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59.8698%;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e\u0026lt;15 Gy, V\u003csub\u003e5\u003c/sub\u003e\u0026lt;50%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 40.1302%;\"\u003e\n \u003cp\u003eHeart (right-side breast cancer)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59.8698%;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e\u0026lt;15 Gy, V\u003csub\u003e5\u003c/sub\u003e\u0026lt;50%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 40.1302%;\"\u003e\n \u003cp\u003eLiver\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59.8698%;\"\u003e\n \u003cp\u003eV\u003csub\u003e5\u003c/sub\u003e\u0026lt;20%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 40.1302%;\"\u003e\n \u003cp\u003eThyroid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59.8698%;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e\u0026lt;30 Gy\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eEvaluation of dosimetric data\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe dosimetric quality of the treatments was measured using a dose-volume histogram (DVH). For CTV, the target coverage (D\u003csub\u003e95\u003c/sub\u003e, D\u003csub\u003e98\u003c/sub\u003e, D\u003csub\u003e99\u003c/sub\u003e, D\u003csub\u003emean\u003c/sub\u003e, D\u003csub\u003e50\u003c/sub\u003e,\u003csub\u003e\u0026nbsp;\u003c/sub\u003eand D\u003csub\u003e2\u003c/sub\u003e) and the conformity index (CI) were reported\u003csup\u003e\u0026nbsp;\u003c/sup\u003e[18-20].\u003c/p\u003e\n\u003cp\u003eCI was defined as\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;CI=(TV\u003csub\u003ePV\u003c/sub\u003e)\u003csup\u003e2\u003c/sup\u003e/(TV\u0026times;PV) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;(1)\u003c/p\u003e\n\u003cp\u003ewhere PV is the volume covered by the prescription isodose. The CI values range between 0 and 1, and a CI close to 1 represents better conformity. Furthermore, dosimetric parameters were evaluated for the\u0026nbsp;lung, heart, spinal cord, breast, liver, thyroid, esophagus, and trachea. The dose administered to the ipsilateral lung was evaluated using V\u003csub\u003e5\u003c/sub\u003e, V\u003csub\u003e10\u003c/sub\u003e, V\u003csub\u003e20\u003c/sub\u003e, and the D\u003csub\u003emean\u003c/sub\u003e, and for the contralateral lung using V\u003csub\u003e5\u003c/sub\u003e, V\u003csub\u003e10\u003c/sub\u003e, and the D\u003csub\u003emean\u003c/sub\u003e; the D\u003csub\u003emax\u003c/sub\u003e of the spinal cord was also recorded. For the heart, the V\u003csub\u003e5\u003c/sub\u003e, V\u003csub\u003e10\u003c/sub\u003e, V\u003csub\u003e20\u003c/sub\u003e, and the D\u003csub\u003emean\u003c/sub\u003e were scored; D\u003csub\u003emax\u003c/sub\u003e and D\u003csub\u003emean\u003c/sub\u003e for the esophagus; D\u003csub\u003emean\u003c/sub\u003e for the thyroid; D\u003csub\u003emean\u003c/sub\u003e for the trachea; and V\u003csub\u003e5\u003c/sub\u003e and D\u003csub\u003emean\u003c/sub\u003e for the liver. D\u003csub\u003ex\u003c/sub\u003e represented the dose (in Gy) received by x% of the volume, V\u003csub\u003ey\u003c/sub\u003e the volume (in percentage) receiving y Gy, D\u003csub\u003emax\u003c/sub\u003e the maximum dose, and D\u003csub\u003emean\u003c/sub\u003e the mean dose.\u003c/p\u003e\n\u003cp\u003eDatasets were statistically analyzed using SPSS 19.0 software (IBM, New York, USA). The dosimetric parameters of the PTV and OARs were compared using the Wilcoxon Cox test. A \u003cem\u003ep\u003c/em\u003e-value \u0026lt;0.05 indicates statistically significant differences.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eSurface imaging system validation\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn summary, we analyzed 255 treatment fractions and 510 breath-hold sessions during beam-on time, which included 12750 points with a one-second interval for DIBH treatment, and 300 treatment fractions and 600 breath-free sessions during beam-on time, which included 69000 points with a one-second interval for FB treatment. The mean treatment session times were 50 s and 230 s for DIBH and FB treatment, respectively. The setup errors (lateral, longitudinal, and vertical) across all patients and sessions during the CBCT session from the AlignRT system and XVI system for DIBH and FB treatments are shown in Table 3. For both treatments, the setup errors were below 0.22 cm. There were significant differences found in the vertical direction for FB and DIBH treatments (p\u0026lt;0.05), and no significant differences were found in other directions for FB and DIBH treatments (p\u0026gt;0.05). The setup deviations between AlignRT and XVI for DIBH treatment were 0.04 cm, 0.08 cm, and 0.02 cm in lat, lng, and vrt directions, respectively, and 0.06 cm, 0.08 cm, and 0.11 cm in lat, lng, and vrt directions for FB treatment, respectively.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3\u003c/strong\u003e The difference of setup errors (mean \u0026plusmn; standard) between the AlignRT system and XVI system for the DIBH and FB treatment during a CBCT session.\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"595\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 17.1429%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" style=\"width: 41.0084%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDIBH (cm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" style=\"width: 41.8487%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFB (cm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 17.1429%;\"\u003e\n \u003cp\u003eParameters\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.958%;\"\u003e\n \u003cp\u003eAlignRT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.71429%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.437%;\"\u003e\n \u003cp\u003eXVI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7.89916%;\"\u003e\n \u003cp\u003ep\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16.3025%;\"\u003e\n \u003cp\u003eAlignRT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 4.70588%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9412%;\"\u003e\n \u003cp\u003eXVI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7.89916%;\"\u003e\n \u003cp\u003ep\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 17.1429%;\"\u003e\n \u003cp\u003eLateral\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.958%;\"\u003e\n \u003cp\u003e-0.05\u0026plusmn;0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.71429%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.437%;\"\u003e\n \u003cp\u003e-0.01\u0026plusmn;0.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7.89916%;\"\u003e\n \u003cp\u003e\u0026gt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16.3025%;\"\u003e\n \u003cp\u003e-0.05\u0026plusmn;0.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 4.70588%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9412%;\"\u003e\n \u003cp\u003e0.11\u0026plusmn;0.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7.89916%;\"\u003e\n \u003cp\u003e\u0026gt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 17.1429%;\"\u003e\n \u003cp\u003eLongitudinal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.958%;\"\u003e\n \u003cp\u003e0.11\u0026plusmn;0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.71429%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.437%;\"\u003e\n \u003cp\u003e0.03\u0026plusmn;0.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7.89916%;\"\u003e\n \u003cp\u003e\u0026gt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16.3025%;\"\u003e\n \u003cp\u003e0.11\u0026plusmn;0.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 4.70588%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9412%;\"\u003e\n \u003cp\u003e-0.19\u0026plusmn;0.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7.89916%;\"\u003e\n \u003cp\u003e\u0026gt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 17.1429%;\"\u003e\n \u003cp\u003eVertical\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.958%;\"\u003e\n \u003cp\u003e0.22\u0026plusmn;0.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 5.71429%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.437%;\"\u003e\n \u003cp\u003e0.20\u0026plusmn;0.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7.89916%;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 16.3025%;\"\u003e\n \u003cp\u003e0.10\u0026plusmn;0.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 4.70588%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9412%;\"\u003e\n \u003cp\u003e0.21\u0026plusmn;0.13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 7.89916%;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eTable 4 shows the result of inter-fraction respiratory motion at beam-on time in terms of mean, standard deviation and \u0026plusmn;95%-confidence interval (CI)\u0026nbsp;for DIBH and FB treatments, respectively. Overall, the mean changes for the maximum magnitude of the respiratory motion on the vertical axis were 0.12\u0026nbsp;\u0026plusmn; 0.12\u0026nbsp;(\u0026plusmn;95%-confidence interval: [-0.12-0.36] cm) and 0.14\u0026nbsp;\u0026plusmn; 0.20\u0026nbsp;(\u0026plusmn;95%-confidence interval: [-0.25-0.53] cm) cm for DIBH and FB treatment, respectively. Along the lateral and longitudinal axes, changes were quite similar: -0.06\u0026plusmn;0.07, 0.12\u0026plusmn;0.15, -0.02\u0026plusmn;0.06, and 0.08\u0026plusmn;0.08 mm for DIBH and FB treatments, respectively. Figure 4 shows histograms representing the differences between conventional patient positioning and the surface-based alignments for DIBH and FB treatment. More than 61.67% and 78.14% of the deviations were smaller than 2 mm in the lateral direction for DIBH and FB, respectively; more than 58.48% and 68.72% of the deviations were smaller than 2 mm in the longitudinal direction for DIBH and FB, respectively; and more than 63.76% and 75.35% of the deviations were smaller than 2 mm in the vertical direction for DIBH and FB, respectively.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4\u003c/strong\u003e The inter-fraction respiratory motion data acquiring by SGRT for FB and DIBH treatment during a beam on time.\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"687\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTreatment\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"9\" style=\"width: 611px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBeam on time\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"3\" style=\"width: 207px;\"\u003e\n \u003cp\u003eLateral (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 202px;\"\u003e\n \u003cp\u003eLongitudinal (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" style=\"width: 202px;\"\u003e\n \u003cp\u003eVertical (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003eMean \u0026plusmn; SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003eCI-95%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003eCI+95%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 81px;\"\u003e\n \u003cp\u003eMean \u0026plusmn; SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003eCI-95%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003eCI+95%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 81px;\"\u003e\n \u003cp\u003eMean \u0026plusmn; SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003eCI-95%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003eCI+95%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eDIBH\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e-0.06\u0026plusmn;0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e-0.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003e0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 81px;\"\u003e\n \u003cp\u003e0.12\u0026plusmn;0.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e-0.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003e0.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 81px;\"\u003e\n \u003cp\u003e0.12\u0026plusmn;0.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e-0.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003e0.36\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e-0.02\u0026plusmn;0.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e-0.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003e0.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 81px;\"\u003e\n \u003cp\u003e0.08\u0026plusmn;0.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e-0.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003e0.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 81px;\"\u003e\n \u003cp\u003e0.14\u0026plusmn;0.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e-0.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 62px;\"\u003e\n \u003cp\u003e0.53\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eTarget doses\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe CTV dosimetric parameters (mean and standard) obtained for the DIBH and FB treatments are shown in Table 5 and Figure 5. The target coverage of the original plans was clinically acceptable for both techniques, with D\u003csub\u003e95\u003c/sub\u003e values of 40.1\u0026plusmn;1.36 Gy and 40.52\u0026plusmn;0.19 Gy for DIBH and VAMT treatments, respectively. For DIBH treatment, the dosimetric parameter differences in the DIBH\u003csub\u003eorg\u003c/sub\u003e plan compared with DIBH\u003csub\u003emin\u003c/sub\u003e and DIBH\u003csub\u003emax\u003c/sub\u003e plans were statistically significant (p\u0026lt;0.05). The mean absolute differences (DIBH\u003csub\u003emax\u003c/sub\u003e-DIBH\u003csub\u003emin\u003c/sub\u003e) \u0026Delta;D\u003csub\u003e95\u003c/sub\u003e, \u0026Delta;D\u003csub\u003e98\u003c/sub\u003e, \u0026Delta;D\u003csub\u003e99\u003c/sub\u003e, \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e, \u0026Delta;D\u003csub\u003e2\u003c/sub\u003e, \u0026Delta;D\u003csub\u003emax\u003c/sub\u003e, \u0026Delta;D\u003csub\u003e50\u003c/sub\u003e, and \u0026Delta;CI were 0.39 Gy, 0.58 Gy, 1.0 Gy, 0.56 Gy, 1.33 Gy, 1.67 Gy, 0.77 Gy, and 0.12 Gy, respectively. For VAMT treatment, there was no significant difference in the D\u003csub\u003e98\u003c/sub\u003e and D\u003csub\u003e99\u003c/sub\u003e of the CTV between FB\u003csub\u003eorg\u003c/sub\u003e and FB\u003csub\u003emax\u003c/sub\u003e plans (p\u0026gt;0.05), and the differences in other parameters were statistically significant (p\u0026lt;0.05). The mean absolute differences (FB\u003csub\u003emax\u003c/sub\u003e-FB\u003csub\u003emin\u003c/sub\u003e) \u0026Delta;D\u003csub\u003e95\u003c/sub\u003e, \u0026Delta;D\u003csub\u003e98\u003c/sub\u003e, \u0026Delta;D\u003csub\u003e99\u003c/sub\u003e, \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e, \u0026Delta;D\u003csub\u003e2\u003c/sub\u003e, \u0026Delta;D\u003csub\u003emax\u003c/sub\u003e, \u0026Delta;D\u003csub\u003e50\u003c/sub\u003e, and \u0026Delta;CI were 2.3 Gy, 3.96 Gy, 4.41 Gy, 1.27 Gy, 2.12 Gy, 3.21 Gy, 1.11 Gy, and 0.07 Gy, respectively. The mean absolute differences in CTV between DIBH\u003csub\u003emin\u003c/sub\u003e and DIBH\u003csub\u003emax\u003c/sub\u003e and FB\u003csub\u003emin\u003c/sub\u003e and FB\u003csub\u003emax\u003c/sub\u003e are shown in Figure 6a. In Figure 6a, for the CTV, the absolute differences in the dosimetric parameters of DIBH treatment were lower than the FB treatment.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 5\u003c/strong\u003e Mean value and range of CTV dosimetric parameters absolute between the original and perturbed DIBH and FB treatments.\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"780\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 56px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVolume\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 79px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameters\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"5\" style=\"width: 301px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDIBH\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 27px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"5\" style=\"width: 316px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFB\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 70px;\"\u003e\n \u003cp\u003eDIBH\u003csub\u003eorg\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 74px;\"\u003e\n \u003cp\u003eDIBH\u003csub\u003emin\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 70px;\"\u003e\n \u003cp\u003eDIBH\u003csub\u003emax\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cem\u003ep\u0026nbsp;\u003c/em\u003evalue\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 76px;\"\u003e\n \u003cp\u003eFB\u003csub\u003eorg\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 74px;\"\u003e\n \u003cp\u003eFB\u003csub\u003emin\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 78px;\"\u003e\n \u003cp\u003eFB\u003csub\u003emax\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 89px;\"\u003e\n \u003cp\u003e\u003cem\u003ep\u0026nbsp;\u003c/em\u003evalue\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003ep1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003ep2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003ep1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003ep2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"8\" style=\"width: 56px;\"\u003e\n \u003cp\u003eCTV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003eD\u003csub\u003e95\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e40.10\u0026plusmn;1.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e39.78\u0026plusmn;0.86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e40.17\u0026plusmn;0.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"8\" valign=\"top\" style=\"width: 27px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e40.52\u0026plusmn;0.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e38.46\u0026plusmn;1.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e40.76\u0026plusmn;0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003eD\u003csub\u003e98\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e39.10\u0026plusmn;1.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e38.59\u0026plusmn;1.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e39.17\u0026plusmn;1.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e40.09\u0026plusmn;0.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e36.54\u0026plusmn;2.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e40.05\u0026plusmn;0.48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e0.795\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003eD\u003csub\u003e99\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e38.37\u0026plusmn;1.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e37.50\u0026plusmn;2.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e38.50\u0026plusmn;1.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e0.097\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e39.79\u0026plusmn;0.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e35.13\u0026plusmn;3.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e39.54\u0026plusmn;0.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e0.173\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e42.42\u0026plusmn;0.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e42.26\u0026plusmn;0.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e42.82\u0026plusmn;0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e43.44\u0026plusmn;1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e42.75\u0026plusmn;1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e44.02\u0026plusmn;1.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003eD\u003csub\u003e2\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e43.69\u0026plusmn;0.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e43.98\u0026plusmn;0.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e45.31\u0026plusmn;0.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e49.27\u0026plusmn;2.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e48.67\u0026plusmn;2.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e50.79\u0026plusmn;3.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003eD\u003csub\u003emax\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e44.11\u0026plusmn;0.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e44.52\u0026plusmn;0.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e46.19\u0026plusmn;0.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e50.54\u0026plusmn;2.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e49.90\u0026plusmn;2.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e53.11\u0026plusmn;3.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003eD\u003csub\u003e50\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e42.75\u0026plusmn;0.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e42.32\u0026plusmn;0.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e43.09\u0026plusmn;0.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e42.43\u0026plusmn;0.86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e41.95\u0026plusmn;0.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e43.06\u0026plusmn;1.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 79px;\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.67\u0026plusmn;0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.49\u0026plusmn;0.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.61\u0026plusmn;0.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e0.67\u0026plusmn;0.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.65\u0026plusmn;0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e0.72\u0026plusmn;0.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eOARs doses\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOARs\u0026rsquo; DVH dosimetric parameters (mean and range values), obtained for the original (DIBH\u003csub\u003eorg\u003c/sub\u003e and FB\u003csub\u003eorg\u003c/sub\u003e) and perturbed (DIBH\u003csub\u003emin\u003c/sub\u003e, DIBH\u003csub\u003emax\u003c/sub\u003e, FB\u003csub\u003emin\u003c/sub\u003e and FB\u003csub\u003emax\u003c/sub\u003e) DIBH and FB treatments, are shown in Table 6 and Figure 6. The mean absolute differences (DIBH\u003csub\u003emax\u003c/sub\u003e-DIBH\u003csub\u003emin\u003c/sub\u003e) \u0026Delta;V\u003csub\u003e5\u003c/sub\u003e, \u0026Delta;V\u003csub\u003e10\u003c/sub\u003e, \u0026Delta;V\u003csub\u003e20\u003c/sub\u003e and \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the heart; \u0026Delta;D\u003csub\u003emax\u003c/sub\u003e of the spinal cord; \u0026Delta;V\u003csub\u003e5\u003c/sub\u003e, \u0026Delta;V\u003csub\u003e10\u003c/sub\u003e, \u0026Delta;V\u003csub\u003e20\u003c/sub\u003e and \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the ipsilateral lung; \u0026Delta;V\u003csub\u003e5\u003c/sub\u003e, \u0026Delta;V\u003csub\u003e10\u003c/sub\u003e and \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the contralateral lung; \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the breast; \u0026Delta;D\u003csub\u003emean\u0026nbsp;\u003c/sub\u003eof the thyroid; \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the trachea; and \u0026Delta;D\u003csub\u003emax\u003c/sub\u003e and \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the esophagus were 3.03 %, 8.64 %, 6.63%, 2.99 Gy, 0.1 Gy, 11.98%, 11.64%, 11.08 %, 4.23 Gy, 0.3 %, 0.13 %, 0.16 Gy, 2.02 Gy, 0.19 Gy, 0.23 Gy, 0.34 Gy, 0.18 Gy, 0.12 % and 0.13 Gy, respectively. The mean absolute differences (FB\u003csub\u003emax\u003c/sub\u003e-FB\u003csub\u003emin\u003c/sub\u003e) \u0026Delta;V\u003csub\u003e5\u003c/sub\u003e, \u0026Delta;V\u003csub\u003e10\u003c/sub\u003e, \u0026Delta;V\u003csub\u003e20\u003c/sub\u003e and \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the heart; \u0026Delta;D\u003csub\u003emax\u003c/sub\u003e of the spinal cord; \u0026Delta;V\u003csub\u003e5\u003c/sub\u003e, \u0026Delta;V\u003csub\u003e10\u003c/sub\u003e, \u0026Delta;V\u003csub\u003e20\u003c/sub\u003e and \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the ipsilateral lung; \u0026Delta;V\u003csub\u003e5\u003c/sub\u003e, \u0026Delta;V\u003csub\u003e10\u003c/sub\u003e and \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the contralateral lung; \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the breast; \u0026Delta;D\u003csub\u003emean\u0026nbsp;\u003c/sub\u003eof the thyroid; \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the trachea; and \u0026Delta;D\u003csub\u003emax\u003c/sub\u003e and \u0026Delta;D\u003csub\u003emean\u003c/sub\u003e of the esophagus were 11.65%, 5.39%, 1.52%, 1.48 Gy, 0.72 Gy, 10.69 %, 11.96%, 10.14 %, 3.45 Gy, 4.76% 1.39%, 0.4 Gy, 0.52 Gy, 0.52 Gy, 0.91 Gy, 1.71 Gy, 0.42 Gy, 5.38% and 0.94 Gy, respectively. The mean absolute differences in OARs between DIBH\u003csub\u003emin\u003c/sub\u003e and DIBH\u003csub\u003emax\u003c/sub\u003e and FB\u003csub\u003emin\u0026nbsp;\u003c/sub\u003eand FB\u003csub\u003emax\u003c/sub\u003e are shown in Figure 7b. In Figure 6b, compared with DIBH treatment, the FB treatment provided a lower mean absolute difference V\u003csub\u003e10\u003c/sub\u003e, V\u003csub\u003e20\u003c/sub\u003e, and D\u003csub\u003emean\u003c/sub\u003e to the heart; V\u003csub\u003e5\u003c/sub\u003e, V\u003csub\u003e20\u003c/sub\u003e, and D\u003csub\u003emean\u003c/sub\u003e to the ipsilateral lung; and D\u003csub\u003emean\u003c/sub\u003e to the breast.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 6\u003c/strong\u003e Mean value and range of OARs dosimetric parameters absolute between the original and perturbed DIBH and FB treatments.\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"780\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVolume\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameters\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"5\" style=\"width: 301px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDIBH\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"5\" style=\"width: 317px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFB\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 70px;\"\u003e\n \u003cp\u003eDIBH\u003csub\u003eorg\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 74px;\"\u003e\n \u003cp\u003eDIBH\u003csub\u003emin\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 70px;\"\u003e\n \u003cp\u003eDIBH\u003csub\u003emax\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cem\u003ep\u0026nbsp;\u003c/em\u003evalue\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 76px;\"\u003e\n \u003cp\u003eFB\u003csub\u003eorg\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 76px;\"\u003e\n \u003cp\u003eFB\u003csub\u003emin\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 78px;\"\u003e\n \u003cp\u003eFB\u003csub\u003emax\u003c/sub\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 89px;\"\u003e\n \u003cp\u003e\u003cem\u003ep\u0026nbsp;\u003c/em\u003evalue\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003ep1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003ep2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003ep1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003ep2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" style=\"width: 66px;\"\u003e\n \u003cp\u003eHeart\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eV\u003csub\u003e5\u003c/sub\u003e (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e4.86\u0026plusmn;2.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e1.83\u0026plusmn;1.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e4.86\u0026plusmn;2.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e11.07\u0026plusmn;9.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e7.18\u0026plusmn;8.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e18.83\u0026plusmn;11.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eV\u003csub\u003e10\u003c/sub\u003e (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e2.75\u0026plusmn;1.94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.71\u0026plusmn;1.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e9.35\u0026plusmn;5.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e2.59\u0026plusmn;3.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e1.12\u0026plusmn;1.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e6.51\u0026plusmn;7.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e0.051\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eV\u003csub\u003e20\u003c/sub\u003e (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e1.56\u0026plusmn;1.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.30\u0026plusmn;0.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e6.93\u0026plusmn;4.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e0.31\u0026plusmn;0.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e0.03\u0026plusmn;0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e1.55\u0026plusmn;2.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e0.144\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e0.104\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e1.83\u0026plusmn;0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e1.13\u0026plusmn;0.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e4.12\u0026plusmn;2.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e2.63\u0026plusmn;0.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e2.17\u0026plusmn;0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e3.65\u0026plusmn;1.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003eSpinal cord\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eD\u003csub\u003emax\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.24\u0026plusmn;0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.20\u0026plusmn;0.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.30\u0026plusmn;0.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e2.82\u0026plusmn;1.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e2.57\u0026plusmn;1.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e3.29\u0026plusmn;2.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" style=\"width: 66px;\"\u003e\n \u003cp\u003eIpsilateral lung\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eV\u003csub\u003e5\u003c/sub\u003e (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e23.50\u0026plusmn;2.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e18.61\u0026plusmn;2.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e30.59\u0026plusmn;3.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e33.46\u0026plusmn;5.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e28.72\u0026plusmn;5.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e39.41\u0026plusmn;6.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eV\u003csub\u003e10\u003c/sub\u003e (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e17.47\u0026plusmn;2.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e12.84\u0026plusmn;2.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e24.48\u0026plusmn;3.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e19.40\u0026plusmn;5.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e14.14\u0026plusmn;4.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e26.10\u0026plusmn;7.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eV\u003csub\u003e20\u003c/sub\u003e (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e12.84\u0026plusmn;1.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e8.55\u0026plusmn;1.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e19.63\u0026plusmn;3.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e6.97\u0026plusmn;4.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e3.0\u0026plusmn;2.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e13.14\u0026plusmn;6.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e6.07\u0026plusmn;0.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e4.48\u0026plusmn;0.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e8.71\u0026plusmn;1.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e6.08\u0026plusmn;1.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e4.80\u0026plusmn;1.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e8.25\u0026plusmn;2.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 66px;\"\u003e\n \u003cp\u003eContralateral lung\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eV\u003csub\u003e5\u003c/sub\u003e (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.01\u0026plusmn;0.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0\u0026plusmn;0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.30\u0026plusmn;0.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e0.347\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e0.229\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e12.37\u0026plusmn;11.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e10.12\u0026plusmn;10.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e14.88\u0026plusmn;12.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eV\u003csub\u003e10\u003c/sub\u003e (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0\u0026plusmn;0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0\u0026plusmn;0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.13\u0026plusmn;0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e0.145\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e0.260\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e1.82\u0026plusmn;2.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e1.19\u0026plusmn;1.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e2.58\u0026plusmn;3.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e0.085\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.22\u0026plusmn;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.18\u0026plusmn;0.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.34\u0026plusmn;0.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e2.28\u0026plusmn;0.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e2.11\u0026plusmn;0.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e2.51\u0026plusmn;1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003eBreast\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e1.19\u0026plusmn;2.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.61\u0026plusmn;0.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e2.63\u0026plusmn;4.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e0.252\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e0.153\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e3.10\u0026plusmn;1.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e2.91\u0026plusmn;1.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e3.43\u0026plusmn;1.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003eThyroid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.29\u0026plusmn;0.13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.22\u0026plusmn;0.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.41\u0026plusmn;0.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e0.83\u0026plusmn;0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e0.63\u0026plusmn;0.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e1.15\u0026plusmn;0.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003eTrachea\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.37\u0026plusmn;0.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.29\u0026plusmn;0.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.52\u0026plusmn;0.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e2.22\u0026plusmn;1.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e1.79\u0026plusmn;1.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e2.70\u0026plusmn;1.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 66px;\"\u003e\n \u003cp\u003eEsophagus\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eD\u003csub\u003emax\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.54\u0026plusmn;0.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.44\u0026plusmn;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.78\u0026plusmn;0.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e5.38\u0026plusmn;2.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e4.68\u0026plusmn;2.58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e6.39\u0026plusmn;3.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.44\u0026plusmn;0.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.26\u0026plusmn;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.44\u0026plusmn;0.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e1.63\u0026plusmn;0.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e1.44\u0026plusmn;0.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e1.86\u0026plusmn;1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 66px;\"\u003e\n \u003cp\u003eLiver\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eV\u003csub\u003e5\u003c/sub\u003e (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0\u0026plusmn;0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0\u0026plusmn;0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.12\u0026plusmn;0.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e0.231\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e0.160\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e7.30\u0026plusmn;5.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e5.17\u0026plusmn;3.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e10.55\u0026plusmn;7.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003eD\u003csub\u003emean\u003c/sub\u003e (Gy)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.17\u0026plusmn;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 74px;\"\u003e\n \u003cp\u003e0.13\u0026plusmn;0.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 70px;\"\u003e\n \u003cp\u003e0.26\u0026plusmn;0.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 44px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e1.65\u0026plusmn;0.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e1.30\u0026plusmn;0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 78px;\"\u003e\n \u003cp\u003e2.24\u0026plusmn;1.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 46px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn recent years, radiotherapy techniques such as FB and DIBH have been used widely in the radiotherapy of breast cancer. The present study addresses the topic of FB and DIBH stability and reproducibility during surface-guided breast radiotherapy. Surface imaging can be used to monitor the chest wall position during DIBH and the FB. We report on intra-breath-hold and intra-free-breath stability and inter-fraction reproducibility during DIBH and FB radiotherapy in a breast cancer patient study (17 patients with 12750 points for DIBH and 20 patients with 69000 points for VMA) and using an Align RT system.\u003c/p\u003e \u003cp\u003eDIBH and FB techniques have different dosimetry advantages in the radiotherapy of breast cancer, respectively. However, in addition to dosimetry considerations, patient positioning and respiratory movement are major concerns for dose delivery in FB and DIBH radiotherapy for breast cancer. This requires patient positioning monitoring be maintained as accurately as possible during treatment to ensure that the dose is delivered as intended. Shah et al. analyzed 50 patients undergoing radiation therapy for whole breast; these patients were aligned daily using optical surface imaging, and shifts from skin marks were recorded, in comparison with MV port films [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Reitz et al. evaluated intra-breath-hold stability and inter-fraction breath-hold reproducibility in clinical practice [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e22\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eCompared with general images from CBCT, SGRT (non-invasive and non-radiative) uses optical surface imaging to verify the position. Several studies have evaluated the setup accuracy of SGRT systems compared to CBCT [\u003cspan additionalcitationids=\"CR24\" citationid=\"CR20\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. In our study, CBCT was used to verify AlignRT system corrections, showing the stability gained when using SGRT for intra-fraction patient setup, where the setup error is similar to CBCT. Average setup differences between both AlignRT and CBCT were below 0.08 cm for DIBH treatment and below 0.11 cm for FB treatment, in three directions. This result is in agreement with previous studies [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Alderliesten et al [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e25\u003c/span\u003e] also compared the AlignRT system to CBCT imaging setup errors for DIBH radiotherapy, and showed similar results. Batin et al. [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e26\u003c/span\u003e] demonstrated that positioning with AlignRT after laser alignment is more accurate than when only the laser is used. In Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, it can be observed that the setup errors from AlignRT were slightly larger than with the CBCT. This is because for the CBCT, the setup error was based on the target volume, but the AlignRT was based on the patient\u0026rsquo;s surface imaging. In addition, due to the different ROI position, AlignRT mainly looks at the ventral side of the breast, which can differ in shape during an optical imaging acquisition session. Thus, AlignRT has reliable patient positioning stability similar to CBCT and the potential to replace CBCT for positioning in breast cancer patients using FB and DIBH.\u003c/p\u003e \u003cp\u003eAt present, analyses of dosimetry between DIBH and FB have been reported in many studies [\u003cspan additionalcitationids=\"CR28\" citationid=\"CR24\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. In addition to dosimetry comparisons, the impact of patient respiration on both techniques needs to be evaluated. Patient respiration can lead to an increase in dose delivery uncertainty, prompting the monitoring of treatment delivery to ensure that the target and OAR-delivered dose correspond to those planned. However, most prior studies did not report dosimetric deviation due to patient respiration during beam-on duration, but mainly focused on the three directions of motion of the patient [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. Zhao et al. [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e15\u003c/span\u003e] compared the impact of positioning errors in FB and tangential field-in-field (TFiF) plans for breast treatments, but the positioning errors in the three directions were artificially set to 3, 5, and 10 mm, and not taken from the surface-guided system. In addition to the advantages provided with SGRT for setup positioning, the main advantage in the present study is the opportunity for real-time monitoring. In this study, firstly, patient respiratory data were acquired from AlignRT for DIBH and FB treatments; secondly, perturbations were introduced to the plans.\u003c/p\u003e \u003cp\u003eIntra-DIBH and intra-FB stability were both smallest in the vertical direction during beam-on time, as shown in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. This may be due to patient respiration factors during beam-on time. The deviation values in the vertical direction averaged over all patients were 0.12\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12 cm for DIBH and 0.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.20 cm for FB, respectively. The average value and standard deviation showed that the respiratory motion amplitude of FB technology is greater than DIBH. The reason for this situation is that patients use FB technology in a state of free breathing, and inhalation and exhalation have a positive and negative relationship in the AlignRT system, which leads to a greater average value. Our surface-based alignments specifically showed that across all patients, skin-mark alignments were poorer in the three directions (especially the deviation within the range from \u0026minus;\u0026thinsp;2 to 2 mm) for DIBH treatment in comparison with the FB treatment (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). This result indicates that the stability of the FB treatment is better than the DIBH treatment of inter-fractional motion. This is because DIBH treatment has higher requirements for patients; patients must be able to hold their breath for at least 25 s and to replicate the breath retention setting five times in succession. One potential solution could involve increasing patient\u0026rsquo;s breath-holding training.\u003c/p\u003e \u003cp\u003eWhen perturbations were introduced to DIBH and FB plans, however, DIBH techniques guaranteed an accurate target coverage with deviations in the target DVH dosimetric, whereas FB plans seemed more sensitive to positioning errors, with mean deviations of 2.3 Gy and 3.96 Gy for D\u003csub\u003e95\u003c/sub\u003e and D\u003csub\u003e98\u003c/sub\u003e, respectively. In Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e(A), it is possible to observe that respiratory movement has a dosimetric impact on CTV that is larger for FB plans than for DIBH plans. Zhao et al. [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e15\u003c/span\u003e] also found such dosimetric effects. For breast cancer radiotherapy, dose sparing of the ipsilateral lung, contralateral breast, and heart are particularly important. For the OARs, DIBH plans appeared to be more sensitive to the positioning errors\u0026rsquo; mean absolute difference (Plan\u003csub\u003emax\u003c/sub\u003e-Plan\u003csub\u003emin\u003c/sub\u003e) for V\u003csub\u003e10\u003c/sub\u003e, V\u003csub\u003e20\u003c/sub\u003e, and D\u003csub\u003emean\u003c/sub\u003e to the heart, V\u003csub\u003e5\u003c/sub\u003e, V\u003csub\u003e20\u003c/sub\u003e, and D\u003csub\u003emean\u003c/sub\u003e to the ipsilateral lung, and D\u003csub\u003emean\u003c/sub\u003e to the breast. In addition, the well-known second cancer risk for contralateral breast and lung forces us to monitor treatment delivery to ensure that the OAR-delivered dose corresponds to the planned one [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. One possible solution is to increase the threshold in the optical surface imaging system, with beam delivery interruption if patients\u0026rsquo; positions exceed their tolerance limits.\u003c/p\u003e \u003cp\u003eOne limitation of this study is that the tolerance of linear translations and rotations are set to 3 mm and 3˚ in the AlignRT system. Xiao et al. [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e31\u003c/span\u003e] reported different values of variabilities (translation 1 mm and rotation 1˚), which resulted in small dosimetric consequences. Thus, a lower tolerance could assure DIBH and FB with good stability and low intra-fraction and inter-fraction variability, contributing to smaller deviations in dosimetric delivery. The three axis rotations from AlignRT were not discussed. Wiant et al. [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e32\u003c/span\u003e] showed that the mean rotations were all \u0026lt;\u0026thinsp;0.1˚ for thirty free-breathing breast patients. This indicates that rotation deviations might negligible in dosimetric delivery.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eTo conclude, due to the large amount of data analyzed, the optical real-time surface imaging system in the present study was demonstrated to be an important tool for inter-fraction patient positioning and intra-fraction patient respiratory motion management in DIBH and FB breast cancer radiotherapy. Regarding the reproducibility of DIBH and FB, the setup deviations between AlignRT and CBCT were both \u0026lt;\u0026thinsp;0.12 cm. As a measure of DIBH and FB stability, the mean deviations were both \u0026lt;\u0026thinsp;0.2 cm. The FB technology has greater possibility for the undercoverage of the target volume, while DIBH technology is more likely to result in increases in dose to organs at risk, especially the lung, heart, and breast. In addition, the tolerance of the optical surface imaging system could be reduced, and could then become a potential method for reducing the dose delivery uncertainty caused by patient respiratory motions.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere is no conflict of interest to declare.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDesign of the research: BT, JXW. Treatment plans: FW, FY. Statistical Analysis: OL, JL, KY, LPX. Manuscript preparation: FY, JXW. Manuscript writing: JXW. Manuscript final revision: BT, XLW. All authors contributed to the article and approved the submitted version.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was supported by Sichuan Natural Science Foundation Program (No. 2024NSFSC1878) and Sichuan Cancer Hospital Youth Project (No. YB2023025, No. YB2021032).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data are fully available without restriction in a public repository (Dryad). The reference treatment plans and corresponding perturbed plans were archived in the Informatic System of Sichuan Cancer Hospital.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDeclarations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis retrospective study was approved by the Ethics Committee of our hospital (Approval Number No. SCCHEC-02-2021-026).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone of the authors have any competing interests (financial and nonfinancial) in the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eZheng RS, Zhang SW, Zeng HM, Wang SM, Sun K, Chen R, et al. Cancer incidence and mortality in China 2016. Journal of the national cancer center. 2022; 2(1): 1-9. \u003c/li\u003e\n\u003cli\u003eOffersen BV, Alsner J, Nielsen HM, et al. Hypofractionated Versus Standard Fractionated Radiotherapy in Patients with Early Breast Cancer or Ductal Carcinoma in Situ in a Randomized Phase III Trial: The DBCG HYPO Trial. Journal of Clinical Oncology. 2020; 38(31): 3615-3625.\u003c/li\u003e\n\u003cli\u003eDarby S, McGale P, Correa C, et al. Effect of radiotherapy after breast-conserving surgery on 10-year recurrence and 15-year breast cancer death: Meta-analysis of individual patient data for 10,801 women in 17 randomised trials. Lancet. 2011; 378: 1707-1716.\u003c/li\u003e\n\u003cli\u003eBrunt AM, Haviland JS, Wheatley DA, et al. Hypofractionated breast radiotherapy for 1 week versus 3 weeks (FAST-Forward): 5-year efficacy and late normal tissue effects results from a multicentre, non-inferiority, randomised, phase 3 trial. Lancet. 2020; 395:1613-1626.\u003c/li\u003e\n\u003cli\u003eTrivedi SJ, Choudhary P, Lo Q, et al. Persistent reduction in global longitudinal strain in the longer term after radiation therapy in patients with breast cancer. Radiother Oncol. 2019; 132:148\u0026ndash;54.\u003c/li\u003e\n\u003cli\u003eHidekazu T, Shinya H, Hiroaki H. Determination of the optimal method for the field-in-field technique in breast tangential radiotherapy. J Radiat Res (Tokyo). 2014; 4 :769\u0026ndash;73. \u003c/li\u003e\n\u003cli\u003eKrasin M, Mccall A, King S, Olson M, Emami B. Evaluation of a standard breast tangent technique: a dose-volume analysis of tangential irradiation using three-dimensional tools. Int J Radiat Oncol Biol Phys. 2000; 47(2):327\u0026ndash;33. \u003c/li\u003e\n\u003cli\u003eOnal C, Sonmez A, Arslan G, Oymak E, Kotek A, Efe E, et al. Dosimetric comparison of the field-in-field technique and tangential wedged beams for breast irradiation. Jpn J Radiol. 2012; 30(3):218\u0026ndash;26. \u003c/li\u003e\n\u003cli\u003eDuma M-N, M\u0026uuml;nch S, Oechsner M, Combs SE. Heart-sparing radiotherapy in patients with breast cancer: what are the techniques used in the clinical routine ?: A pattern of practice survey in the german-speaking countries. Med Dosim. 2017; 42(3):197\u0026ndash;202.\u003c/li\u003e\n\u003cli\u003eBoda-Heggemann J, Knopf A-C, Simeonova-Chergou A, Wertz H, Stieler F, Jahnke A, et al. Deep inspiration breath hold-based radiation therapy: a clinical review. Int J Radiat Oncol Biol Phys. 2016; 94(3):478\u0026ndash;92.\u003c/li\u003e\n\u003cli\u003eDonovan E, Bleakley N, Denholm E, Evans P, Gothard L, Hanson J, et al. Randomised trial of standard 2D radiotherapy (RT) versus intensity modulated radiotherapy (IMRT) in patients prescribed breast radiotherapy. Radiother Oncol. 2007; 82(3):254\u0026ndash;64. \u003c/li\u003e\n\u003cli\u003eHo AY, Mccormick B. A multicenter randomized trial of breast intensity-modulated radiation therapy to reduce acute radiation dermatitis. J Clin Oncol. 2009; 20(1):89\u0026ndash;90. \u003c/li\u003e\n\u003cli\u003eCho HL, Park ET, Kim JY, et al. Evaluation of radiotherapy setup accuracy for head and neck cancer using a 3‐D surface imaging system. J Instrumm. 2013; 8: T11002.\u003c/li\u003e\n\u003cli\u003eCervino LI, Gupta S, Rose MA, Yashar C, Jiang SB. Using surface imaging and visual coaching to improve the reproducibility and stability of deep‐inspiration breath hold for left‐breast‐cancer radiotherapy. Phys Med Biol. 2009; 54:6853\u0026ndash;6865.\u003c/li\u003e\n\u003cli\u003eZhao YQ, Diao P, Zhang D, et al. Impact of positioning errors on the dosimetry of breath-hold-based volumetric arc modulated and tangential field-in-field left-sided breast treatments [J]. Front Oncol. 2020;10:554131.\u003c/li\u003e\n\u003cli\u003eXin X, Li J, Zhao YQ, et al. Retrospective study on left-sided breast radiotherapy: dosimetric results and correlation with physical factors for free breathing and breath hold irradiation techniques [J]. Technol Cancer Res T. 2021; 20:1-8.\u003c/li\u003e\n\u003cli\u003eTaylor CW, Wang Z, Macaulay E, et al. Exposure of the heart in breast cancer radiation therapy: a systematic review of heart doses published during 2003 to 2013. Int J Radiat Oncol Biol Phys. 2015;93(4):845-853. \u003c/li\u003e\n\u003cli\u003eAudet C, Poffenbarger BA, Chang P, Jackson PS, Lundahl RE, Ryu SI, et al. Evaluation of volumetric modulated arc therapy for cranial radiosurgery using multiple noncoplanar arcs. Med Phys. 2011; 38(11):5863-5872. \u003c/li\u003e\n\u003cli\u003ePaddick I. A simple scoring ratio to index the conformity of radiosurgical treatment plans. J Neurosurg. 2000; 93(3):219-222. \u003c/li\u003e\n\u003cli\u003ePaddick I, Lippitz B. A simple dose gradient measurement tool to complement the conformity index. J Neurosurg. 2006; 123:194-201. \u003c/li\u003e\n\u003cli\u003eShah AP, Dvorak T, Curry MS, et al. Clinical evaluation of interfractional variations for whole breast radiotherapy using 3-dimensional surface imaging. Pract Radiat Oncol. 2013; 3(1):16-25.\u003c/li\u003e\n\u003cli\u003eReitz D, Walter F, Sch\u0026ouml;necker S, et al. Stability and reproducibility of 6013 deep inspiration breath-holds in left-sided breast cancer. Radiat Oncol. 2020; 15: 121.\u003c/li\u003e\n\u003cli\u003eHamming VC, Visser C, Batin E, et al. Evaluation of a 3D surface imaging system for deep inspiration breath-hold patient positioning and intra-fraction monitoring. Radiat Oncol. 2019;14:125.\u003c/li\u003e\n\u003cli\u003eMacFarlane MJ, Jiang K, Mundis M, et al. Comparison of the dosimetric accuracy of proton breast treatment plans delivered with SGRT and CBCT setups. J Appl Clin Med Phys. 2021;00:1-6.\u003c/li\u003e\n\u003cli\u003eAlderliesten T, Sonke JJ, Betgen A, et al. Accuracy evaluation of a 3-dimensional surface imaging system for guidance in deep-inspiration breath-hold radiation therapy. Int J Radiat Oncol Biol Phys. 2013; 85:536\u0026ndash;542.\u003c/li\u003e\n\u003cli\u003eCravo S\u0026aacute; A, Fermento A, Neves D, et al. Radiotherapy setup displacements in breast cancer patients: 3D surface imaging experience. Rep Pract Oncol Radiother. 2018;23(1):61\u0026ndash;67.\u003c/li\u003e\n\u003cli\u003eLoap P, Vu-Bezin J, Monceau V, et al. Dosimetric evaluation of the benefit of deep inspiration breath hold (DIBH) for locoregional irradiation of right breast cancer with volumetric modulated arctherapy (FB). Acta Oncologica. 2023; 62(2): 150\u0026ndash;158.\u003c/li\u003e\n\u003cli\u003eDumane VA, Saksornchai K, Zhou Y, et al. Reduction in low-dose to normal tissue with the addition of deep inspiration breath hold (DIBH) to volumetric modulated arc therapy (FB) in breast cancer patients with implant reconstruction receiving regional nodal irradiation. Radiat Oncol. 2018; 13:187.\u003c/li\u003e\n\u003cli\u003eJin GH, Chen LX, Deng XW, et al. A comparative dosimetric study for treating left-sided breast cancer for small breast size using five different radiotherapy techniques: conventional tangential field, filed-in-filed, Tangential-IMRT, Multi-beam IMRT and FB. Radiat Oncol. 2013; 8: 89.\u003c/li\u003e\n\u003cli\u003eReitz D, Carl H, Sch\u0026ouml;necker S, et al. Real-time intra-fraction motion management in breast cancer radiotherapy: analysis of 2028 treatment sessions. Radiat Oncol. 2018; 13: 128.\u003c/li\u003e\n\u003cli\u003eXiao A, Crosby J, Malin M, et al. Single institution report of setup margins of voluntary deep-inspiration breath-hold (DIBH) whole breast radiotherapy implemented with real-time surface imaging. J Appl Clin Med Phys. 2018; 19:205\u0026ndash;13.\u003c/li\u003e\n\u003cli\u003eAbo-Madyan Y, Aziz MH, Aly MMOM, et al. Second cancer risk after 3D-CRT, IMRT and FB for breast cancer. Radiother Oncol. 2014; 110(3): 471\u0026ndash;6.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"radiation-oncology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"raon","sideBox":"Learn more about [Radiation Oncology](http://ro-journal.biomedcentral.com/)","snPcode":"13014","submissionUrl":"https://submission.nature.com/new-submission/13014/3","title":"Radiation Oncology","twitterHandle":"@OncoBioMed","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Surface guided radiotherapy, Deep inspiration breath hold, Volumetric modulated arc therapy, Breast cancer","lastPublishedDoi":"10.21203/rs.3.rs-4962651/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4962651/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eThe aim of this study was to evaluate the inter-fraction reproducibility and intra-fraction stability of breast radiotherapy using deep-inspiration breath hold (DIBH) and free breathing (FB) based on an optical surface imaging system (OSIS).\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eSeventeen patients (510 breath-hold sessions) treated using a field-in-field (FiF) technique and twenty patients (600 breath-free sessions) treated with a volume-modulated arc therapy (VMAT) technique were included in this retrospective study. All the patients were positioned with the guidance of CBCT and OSIS, and also monitored with OSIS throughout the whole treatment session. Eight setup variations in three directions were extracted from the treatment reports of OSIS for all sessions and were subsequently manually introduced to treatment plans, resulting in a total of 296 perturbed plans. All perturbed plans were recalculated, and the dose volume histograms (DVH) for the target and organs at risk (OAR) were analyzed.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe OSIS and CBCT for both DIBH and FB treatments showed a good agreement of less than 0.12 cm in each direction. The intra-fraction setup errors during DIBH were \u0026minus;\u0026thinsp;0.06\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07 cm, 0.12\u0026thinsp;\u0026plusmn;\u0026thinsp;0.15 cm, and 0.12\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12 cm in the lateral, longitudinal, and vertical directions, respectively; for FB, the errors were \u0026minus;\u0026thinsp;0.02\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12 cm, 0.08\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18 cm, and 0.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.20 cm, respectively. For the target, DIBH plans were more sensitive to positioning errors; the mean deviations in D\u003csub\u003e95\u003c/sub\u003e for CTV were 39.78 Gy-40.17 Gy for DIBH and 38.46 Gy-40.52 Gy for FB, respectively. For the OARs, the mean deviations\u0026mdash;V\u003csub\u003e10\u003c/sub\u003e, V\u003csub\u003e20\u003c/sub\u003e, and D\u003csub\u003emean\u003c/sub\u003e to the heart; V\u003csub\u003e5\u003c/sub\u003e, V\u003csub\u003e20\u003c/sub\u003e, and D\u003csub\u003emean\u003c/sub\u003e to the ipsilateral lung; and D\u003csub\u003emean\u003c/sub\u003e to the breast\u0026mdash;were lower for the FB plan compared with the DIBH plan.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eSGRT can be an important tool for inter-fraction patient positioning and intra-fraction patient respiratory motion management in DIBH and FB breast cancer radiotherapy. The FB technology has greater possibility for the undercoverage of the target volume, while DIBH technology is more likely to result in increases in dose to organs at risk, especially the lung, heart, and breast. Furthermore, the tolerance of optical surface imaging systems could be reduced, indicating a potential method to reduce the dose delivery uncertainty caused by the patient\u0026rsquo;s respiratory motion.\u003c/p\u003e","manuscriptTitle":"Reproducibility and stability of deep inspiration breath hold and free breath in breast radiotherapy based on real-time 3-dimensional optical surface imaging system","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-10-17 04:50:50","doi":"10.21203/rs.3.rs-4962651/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-09-23T14:46:55+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-09-20T05:10:04+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-09-18T03:40:39+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-09-14T00:27:36+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-09-09T07:29:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"329271031649494933285250550433422340216","date":"2024-09-06T13:01:50+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"203199709157271344924233832384999252526","date":"2024-09-06T07:35:28+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"209833994737853869482218600946301700944","date":"2024-09-05T11:16:18+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"15998129695055877968905570595094820524","date":"2024-09-04T08:31:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"317098223533823966289230066124759184700","date":"2024-09-04T08:28:23+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-09-04T08:18:57+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-09-02T09:38:39+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-08-26T12:21:51+00:00","index":"","fulltext":""},{"type":"submitted","content":"Radiation Oncology","date":"2024-08-23T08:21:13+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"radiation-oncology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"raon","sideBox":"Learn more about [Radiation Oncology](http://ro-journal.biomedcentral.com/)","snPcode":"13014","submissionUrl":"https://submission.nature.com/new-submission/13014/3","title":"Radiation Oncology","twitterHandle":"@OncoBioMed","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"5b40f36a-26f0-4987-9799-5c4f0d193fd2","owner":[],"postedDate":"October 17th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-11-18T19:17:02+00:00","versionOfRecord":{"articleIdentity":"rs-4962651","link":"https://doi.org/10.1186/s13014-024-02549-9","journal":{"identity":"radiation-oncology","isVorOnly":false,"title":"Radiation Oncology"},"publishedOn":"2024-11-11 15:57:49","publishedOnDateReadable":"November 11th, 2024"},"versionCreatedAt":"2024-10-17 04:50:50","video":"","vorDoi":"10.1186/s13014-024-02549-9","vorDoiUrl":"https://doi.org/10.1186/s13014-024-02549-9","workflowStages":[]},"version":"v1","identity":"rs-4962651","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4962651","identity":"rs-4962651","version":["v1"]},"buildId":"rHA-KDH7Qsr4HCuvH75dn","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}