Exploration of the Feasibility of One-day Dual-low-activity 68Ga-DOTATATE and 18F-FDG PET/MR in Patients with Neuroendocrine Neoplasms

Exploration of the Feasibility of One-day Dual-low-activity 68Ga-DOTATATE and 18F-FDG PET/MR in Patients with Neuroendocrine Neoplasms | 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 Exploration of the Feasibility of One-day Dual-low-activity 68 Ga-DOTATATE and 18F-FDG PET/MR in Patients with Neuroendocrine Neoplasms Wenjin Zhao, Lifang Pang, Yunze Xie, Wenxin Tang, hongcheng Shi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7718410/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 12 Feb, 2026 Read the published version in Molecular Imaging and Biology → Version 1 posted 5 You are reading this latest preprint version Abstract Purpose The standard 2-day dual-tracer PET protocol provides more information but is time consuming. Thus, this study aimed to validate the feasibility of 1-day 68 Ga-DOTATATE and 18 F-FDG dual-low-activity PET/MR imaging in patient with neuroendocrine neoplasms (NENs). Procedures: Fourteen pairs of NENs patients who underwent 1-day 68 Ga-DOTATATE and 18 F-FDG dual-low-activity PET/MR and 2-day 68 Ga-DOTATATE and 18 F-FDG PET/MR were retrospectively enrolled. Imaging analysis was performed, including lesion detection rate and diagnostic confidence. Additionally, the diagnostic confidence was also assessed based on 68 Ga-DOTATATE PET, 18 F-FDG PET and PET/MR, respectively. Results The 1-day protocol detected 39 out of 40 lesions in 14 patients, while the 2-day protocol detected 67 out of 68 lesions in 14 patients. No significant differences were observed in lesion detection (all P > 0.05). There was no significant difference in diagnostic confidence between the 1-day protocol and the 2-day protocol for 68 Ga-DOTATATE PET (median [IQR]: 3[2–3] vs. 3[2–3]), 18 F-FDG PET (1[1–2] vs. 1[1–1]), and PET/MR (4[3–5] vs. 5[4–5]) in all lesions (all P > 0.05). Conclusion the 1-day 68 Ga-DOTATATE and 18 F-FDG dual-low-activity PET/MR imaging protocol in patients with NENs is feasible and provides equivalent lesion detection and diagnostic confidence compared to the 2-day protocol. Dual tracer 18F-FDG 68Ga-DOTATATE NEN PET/MR Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction Neuroendocrine neoplasms (NEN) are a highly heterogeneous group of neoplasms, classified into neuroendocrine tumor (NET) G1, G2, G3 and neuroendocrine carcinoma (NEC) based on cellular morphology and Ki-67 proliferation index. Most well-differentiated NENs exhibit overexpression of somatostatin receptors (SSTRSs), providing a specific target for molecular imaging techniques utilizing somatostatin analogs. ( 1 ) 68 Ga-DOTATATE PET imaging, based on SSTRS analogs, is currently a preferred imaging modality for patients with suspected NENs, offering high specificity and sensitivity. ( 2 ) Besides, 18 F-FDG PET, widely used in the imaging of malignant tumors, has demonstrated increasing value in poorly differentiated NENs with low SSTRS expression. A positive 18 F-FDG PET imaging often indicates a more aggressive tumor phenotype and is associated with a poorer patient prognosis. ( 3 , 4 ) Consequently, dual-tracer PET using both 68 Ga-DOTATATE and 18 F-FDG has gained increasing attention for its potential value in NENs. For instance, Kayani et al. found that combining 68 Ga-DOTATATE and 18 F-FDG PET/CT provided a better assessment of intermediate- and high-grade NENs. ( 5 ) Zhou et al. revealed that diverse uptake patterns of 68 Ga-DOTATATE and 18 F-FDG in newly diagnosed NENs was significantly associated with progression-free survival. ( 6 ) However, most previous studies employed a 2-day PET protocol, which increased time cost. What’s more, while PET/MR has been increasingly applied in oncology in recent years due to its lower radiation dose and superior soft tissue resolution, the efficiency of dual-tracer PET/MR imaging in NENs remains unreported. Therefore, the aim of this study was to validate the feasibility of 1-day 68 Ga-DOTATATE and 18 F-FDG PET/MR imaging with dual-low-activity compared with 2-day protocol. Materials and methods Study population This single-center retrospective study was approved by our institution’s ethics committee (No. B2025-175R). Informed written consent was obtained from each patient. Patients with NENs who underwent 1-day dual-low-activity 68 Ga-DOTATATE and 18 F-FDG PET/MR imaging, hereafter referred to as the 1-day protocol, at our hospital between February and July 2024 were reviewed. Fourteen patients with NENs confirmed by pathology performed 1-day protocol were included. Then, another 14 patients with NENs underwent regular-activity 68 Ga-DOTATATE and 18 F-FDG PET/MR imaging on separate days, hereafter referred to as the 2-day protocol, were included as control. These patients were matched to the 1-day protocol cohort based on pathology. The patient recruitment process is shown in Fig. 1 . Patient preparation and injection In the 2-day protocol, the 68 Ga-DOTATATE (2.00 MBq/kg) and 18 F-FDG (3.70 MBq/kg) PET/MR scan were performed on two separate days, and were both performed about 1 hour after radiotracer injection. In the 1-day protocol, patients first underwent 68 Ga-DOTATATE (1.33 MBq/kg) PET/MR scan about 1 hour after the injection, followed by 18 F-FDG (1.85 MBq/kg) PET/MR scan about 1 hour after the injection. All patients were required to fast for at least 6 hours before the 18 F-FDG injection with blood glucose not exceeding 11 mmol/L. PET/MR protocol The dual-tracer PET/MR (United Imaging Healthcare Co.Limited, Shanghai, China) scan included a whole-body scan and then a dedicated abdomen-pelvis scan with respiratory gating PET and MRI acquisition at the same time for each tracer. The whole-body PET/MR scan consisted of 5 beds, each involving a 3-minute PET acquisition and a 2-sequence MRI acquisition: 3D Dixon-based T1 water-fat imaging (WFI) sequence for attenuation correction and axial T2 single-shot fast-spin-echo (SSFSE) sequence. The dedicated abdomen-pelvis PET/MR scan include a 15-minute PET acquisition for abdomen and a 10-minute PET acquisition for pelvis, including 3D T1 WFI, axial and coronal T2 fat suppression (FS)-FSE and axial echo planar imaging-diffusion weighted imaging (EPI-DWI) sequence for each bed. In the 1-day protocol, the dedicated abdomen-pelvis scan was omitted from the 18 F-FDG PET/MR scan. In the 2-day protocol, the EPI-DWI sequence was omitted from the ¹⁸F-FDG PET/MR scan. The two protocols are illustrated in Fig. 2 , and the detailed information about the MRI sequences is provided in Table 1 . Table 1 MRI sequence parameters Parameter T1 WFI T2 SSFSE T2 FS-FSE EPI-DWI Imaging plane 3D Axial Axial/coronal Axial Voxel size, mm 1.52×1.37×4.00 1.79×1.34×6.00 1.58×1.19×6.00 2.97×2.97×6.00 Repetition time, ms 4.94 1100 3500/4000 4000 Echo time, ms 2.24 82.5 99.32 66.9 Flip angle, degrees 10 160 90 90 Section thickness, mm 4 6 6 6 Field of view, mm 350×500 450×320 380×300 380×300 Intersection gap / 20% 20% 20% No. of signals acquired 1 1 2 / Receiver bandwidth, Hz 1080 500 700 2100 b value, mm/s 2 / / / 50, 800 Scan time, s 141 32, 47, 52 84, 96 212 Respiratory gating + + + + EPI-DWI, echo planar imaging-diffusion weighted imaging; FS-FSE, fat suppression fast-spin-echo; SSFSE, single-shot fast-spin-echo; WFI, water-fat imaging. Imaging analysis Two nuclear medicine physicians (H.G. and Y.X.) independently analyzed all patient images in random order, assessing lesion detection, diagnostic confidence, and tracer uptake heterogeneity. Both were blinded to clinical data. In cases of disagreement between the two physicians, consensus was reached through discussion. A lesion took up any radiotracer beyond the adjacent normal tissue was considered detected on PET images. On MRI, a lesion was considered detected if it displayed a signal different from adjacent tissue on any sequence. In PET/MR images, a lesion was considered detected if its tracer uptake exceeded that of adjacent normal tissue on PET, or if an abnormal signal was present in the corresponding area on any MRI sequence. For organs with multiple metastases, two nuclear medicine physicians (L.P. and W.Z.) jointly selected up to 10 lesions per organ: the five with the lowest 68 Ga-DOTATATE uptake on dedicated abdomen-pelvis PET images and the five with the smallest short-axis diameter on FS-FSE T2WI. Diagnostic confidence for all selected lesions was independently assessed on 68 Ga-DOTATATE PET, 18 F-FDG PET, and PET/MR images using a 5-point Likert scale (1-not at all confident, 2-not very confident, 3-neutral, 4-confident, 5-very confident). For PET images, higher tracer uptake in a lesion was considered to correspond to greater diagnostic confidence. For MRI images, more pronounced lesion signal alterations and number of sequences showing these abnormal signals were associated with higher diagnostic confidence. To minimize potential memory effects, diagnostic confidence evaluations of different imaging sets were conducted at 4-week intervals. The evaluation was further subdivided into lesions confirmed by pathology (lesion P ), lesions confirmed by imaging follow-up (lesion F ), G1 NETs, G2 NETs and NEC subgroup. Intra-lesional tumor heterogeneity for lesions confirmed by pathology was evaluated based on the combined uptake patterns of 68 Ga-DOTATATE and 18 F-FDG. On each PET scan, lesions with significant tracer uptake (diagnostic confidence score of 4 or 5) were assigned "++"; those with mild to moderate uptake (diagnostic confidence score of 2 or 3) were assigned "+"; and those with no tracer uptake (diagnostic confidence score of 1) were assigned "-" Besides, spherical volumes of interest (VOI) were drawn around each lesion on 68 Ga-DOTATATE dedicated abdomen-pelvis PET images and 18 F-FDG PET images (with VOI drawn on whole-body PET images for the 1-day protocol and on abdomen-pelvis PET images for the 2-day protocol), with the maximum standard uptake value (SUV max ) automatically calculated. Reference standard Primary tumors were confirmed by pathology. For metastases that could not be confirmed by pathology due to ethical considerations, a diagnosis of malignancy was established based on follow-up contrast-enhanced CT or MRI, with a minimum follow-up period of 2 months. Statistical analysis All statistical analyses were performed using SPSS (version 22.0; IBM SPSS Inc., IL, USA). The normality of continuous variables was tested using the Kolmogorov-Smirnov test and Shapiro-Wilk test as appropriate. The homogeneity of variance was tested using the Levene test. Continuous variables are presented as mean ± standard deviation or median and interquartile range as appropriate. Categorical variables are represented by absolute values and percentages. The means of variables with normal continuous distributions and the medians of variables with non-normal continuous distributions in two cohorts were compared using the two independent-sample t-test and the Mann-Whitney U test, respectively. The categorical variables were compared using the Fisher’s exact test. A P value < .05 indicated a statistically significant difference. Results A total of 14 patients with NENs were included in the 1-day protocol cohort, and another 14 pathologically matched patients were included in the 2-day protocol cohort. Basic information The patient information is presented in Table 2 . No significant differences were observed between the 1-day and the 2-day protocol cohort in terms of age, sex, BMI, or NENs grading (all P > 0.05). Table 2 Baseline characteristics of patients Variable 1-day protocol 2-day protocol P value (N = 14) (N = 14) Sex, male 12(85.71%) 9(64.29%) 0.385 Age, year 53.00 ± 12.21 54.50 ± 10.88 0.270 BMI, kg/m² 24.74 ± 2.89 24.61 ± 2.63 0.868 Tracer dose, MBq 6.01 ± 0.92 11.52 ± 1.29 <.001 Pathological diagnosis G1 duodenal NET 2 2 G1 rectal NET 2 2 G1 pancreatic NET 3 3 G2 gastric NET 1 1 G2 duodenal NET 2 2 G2 rectal NET 2 2 G2 pancreatic NET 1 1 Pancreatic NEC 1 1 Values are absolute value (percentage) or mean ± standard deviation. BMI, body mass index; NEC, neuroendocrine carcinoma; NET, neuroendocrine tumor. In the 1-day protocol cohort, a total of 40 lesions were included. Among them, 13 primary tumors in 14 patients were confirmed by pathology (one patient had two primary tumors, and 2 patients had undergone surgical resection of primary tumors prior to PET/MR imaging). These 2 patients also underwent liver biopsy, which confirmed that the hepatic lesions were metastases originating from the resected primary tumors. In addition, 2 lymph node metastases and 25 distant metastases, both confirmed by imaging follow-up. In the 2-day protocol cohort, a total of 66 lesions in 14 patients were included. Among of them, 15 primary tumors confirmed by pathology (2 patients each had two primary tumors, and 1 patient had undergone surgical resection of the primary tumor prior to PET/MR imaging), 14 lymph node metastases and 37 distant metastases, both confirmed by imaging follow-up. Lesion detection As shown in Table 3 , no significant differences were observed between the two cohorts in the lesion detection rates or short-axis diameter. The 1-day protocol detected 39 out of 40 lesions, while the 2-day protocol detected 65 out of 66 lesions. In the 1-day protocol cohort, the detected smallest lesion was a 2.0 mm diameter liver metastasis in a patient with G2 duodenal NET (Fig. 3 A-C), and the lowest 68 Ga-DOTATATE uptake lesion was a primary tumor with SUV max of 2.91 in a patient with G1 rectal NET (Fig. 3 D-F). In the 2-day protocol cohort, the detected smallest lesion was a 2.6 mm diameter liver metastasis in a patient with G2 rectal NET (Fig. 3 G-I), and the lowest 68 Ga-DOTATATE uptake lesion was a lymph node metastasis with SUV max of 0.54 in a patient with G2 rectal NET, identified through MRI images (Fig. 3 J-L). Both protocols failed to detect one G1 rectal primary tumor. Furthermore, for the lesion P and lesion F subgroups, lesion detection rates did not show any significant differences between protocols (all P > 0.05). Table 3 Comparisons of the lesion detection between 1-day and 2-day protocol cohort 1-day protocol 2-day protocol P value All lesions 39(97.50%) 65(98.48%) 1.000 Short-axis diameter, mm 6.7(3.3–10.2) 5.4(3.9–10.5) 0.877 8.2 ± 6.0 9.2 ± 9.1 SUV max 1 68 Ga-DOTATATE 5.1(4.0-19.1) 9.2(5.4–27.8) 0.049 17.1 ± 25.2 20.6 ± 25.2 18 F-FDG 3.0(2.4-4.0) 1.5(1.2-2.0) <.001 3.8 ± 3.2 2.4 ± 3.0 Lesions P 2 12(92.31%) 14(93.33%) 1.000 Short-axis diameter, mm 10.3(8.1–14.1) 14.6(9.1–21.1) 0.231 12.0 ± 5.9 18.0 ± 13.6 SUV max 68 Ga-DOTATATE 16.0(4.8–47.1) 29.8(20.4–35.7) 0.252 34.2 ± 39.4 42.0 ± 38.0 18 F-FDG 4.2(3.0-6.6) 1.9(1.2–3.8) 0.020 5.9 ± 5.2 3.5 ± 4.6 Lesions F 3 27(100%) 51(100%) N/A 4 Short-axis diameter, mm 4.2(3.0-9.3) 4.7(3.9–6.2) 0.401 6.6 ± 5.4 6.8 ± 5.6 SUV max 68 Ga-DOTATATE 5.1(3.8–15.1) 7.1(5.1–18.3) 0.052 9.5 ± 8.5 14.7 ± 16.5 18 F-FDG 2.7(2.3–3.4) 1.5(1.2–1.9) <.001 2.9 ± 0.8 2.1 ± 2.4 Values are absolute value (percentage) or median (interquartile range) or mean ± standard deviation. 1. SUV max indicates maximum standard uptake value 2. Lesions P indicates lesions confirmed by pathology 3. Lesions F indicates lesions confirmed by imaging follow-up 4. N/A indicates not applicable Diagnostic confidence As shown in Table 4 , no significant differences were observed in diagnostic confidence between the 1-day and 2-day protocols for all lesions, lesions P , lesion F or G2 NETs when evaluating lesions using 68 Ga-DOTATATE PET, 18 F-FDG PET or PET/MR images (all P > 0.05). For the G1 NETs subgroup, no significant differences were observed in the diagnostic confidence between cohorts when using 68 Ga-DOTATATE PET or PET/MR images. However, the 18 F-FDG PET diagnostic confidence was slightly higher in the 1-day protocol cohort than in the 2-day protocol cohort. Since only one NEC lesion was presented in the 1-day protocol, statistical analysis was not performed. Table 4 Comparisons of the diagnostic confidence between 1-day and 2-day protocol cohort 1-day protocol 2-day protocol P value DOTATATE PET FDG PET PET/MR DOTATATE PET FDG PET PET/MR DOTATATE PET FDG PET PET/MR All lesions 3( 1 – 3 ) 1( 1 – 2 ) 4( 3 – 5 ) 3( 2 – 3 ) 1( 1 – 1 ) 5( 3 – 5 ) 0.167 0.188 0.119 Lesions P 1 3( 2 – 3 ) 2( 1 – 3 ) 4( 3 – 5 ) 3( 3 – 3 ) 1( 1 – 2 ) 5( 5 – 5 ) 0.316 0.156 0.185 Lesions F 2 2( 1 – 3 ) 1( 1 – 1 ) 4( 3 – 5 ) 3( 2 – 3 ) 1( 1 – 1 ) 5( 3 – 5 ) 0.178 0.563 0.231 G1 NETs 3( 2 – 3 ) 2( 2 – 3 ) 4( 4 – 5 ) 3( 3 – 3 ) 1( 1 – 1 ) 5( 4 – 5 ) 0.351 0.016 0.606 G2 NETs 3( 1 – 3 ) 1( 1 – 1 ) 5( 4 – 5 ) 3( 1 – 3 ) 1( 1 – 1 ) 5( 3 – 5 ) 0.681 0.967 0.337 NEC 2 2 4 3( 3 – 3 ) 1( 1 – 2 ) 5( 5 – 5 ) N/A 3 N/A N/A Values are medians (interquartile range). 1. Lesions P indicates lesions confirmed by pathology 2. Lesions F indicates lesions confirmed by imaging follow-up 3. N/A indicates not applicable Tumor uptake patterns of the dual tracer Table 5 presents the different uptake patterns of 68 Ga-DOTATATE and 18 F-FDG in the two cohorts. In the 1-day protocol, 5 G1, 3 G2, 1 NEC primary tumors, 2 lymph node and 2 liver metastases were positive for both 68 Ga-DOTATATE and 18 F-FDG PET, 1 G1 pancreatic primary tumor, 2 G2 duodenal primary tumors 1 bone and 19 liver metastases were positive for 68 Ga-DOTATATE PET and negative for 18 F-FDG PET, and 1 G1 rectal primary tumor and 3 liver metastases were negative for both 68 Ga-DOTATATE and 18 F-FDG PET. Figure 4 shows PET/MR images of a patient from the 1-day protocol cohort diagnosed with G2 pancreatic NET. Table 5 a Different uptake patterns in primary tumors of the both cohorts 1-day protocol DOTATATE uptake pattern Number (++) 1 (+) 2 (-) 3 FDG uptake pattern (++) 4 0 0 4 (+) 3 2 0 5 (-) 2 1 1 4 Number 9 3 1 13 2-day protocol DOTATATE uptake pattern Number (++) (+) (-) FDG uptake pattern (++) 3 0 0 3 (+) 3 0 0 3 (-) 8 0 1 9 Number 14 0 1 15 1. ++ indicates lesion presents significant tracer uptake 2. + indicates lesion presents mild to moderate tracer uptake 3. - indicates lesion presents no tracer uptake. Table 5 b Different uptake patterns in metastases of the both cohorts 1-day protocol DOTATATE uptake pattern Number (++) (+) (-) FDG uptake pattern (++) 1 0 0 1 (+) 2 1 0 3 (-) 8 12 3 23 Number 11 13 3 27 2-day protocol DOTATATE uptake pattern Number (++) (+) (-) FDG uptake pattern (++) 4 0 0 4 (+) 4 0 0 4 (-) 21 16 6 43 Number 29 16 6 51 ++ indicates lesion presents significant tracer uptake, + indicates lesion presents mild to moderate tracer uptake, - indicates lesion presents no tracer uptake. In the 2-day protocol, 6 G2 primary tumors, 6 lymph node, 1 implantation and 1 liver metastases were positive for both 68 Ga-DOTATATE and 18 F-FDG PET, 8 G1 primary tumors, 7 lymph node, 2 bone and 28 liver metastases were positive for 68 Ga-DOTATATE PET and negative for 18 F-FDG PET, and 1 G1 rectal primary tumor, 1 lymph node and 5 liver metastases were negative for both 68 Ga-DOTATATE and 18 F-FDG PET. Figure 5 displays PET/MR images of a patient from the 2-day protocol cohort diagnosed with G2 rectal NET. Discussion In this study, primary tumors in the 1-day and 2-day protocol cohorts were matched based on pathology diagnosis. No significant differences were found in lesion detection rates or diagnostic confidence between the two cohorts, including 13 primary tumors confirmed by pathology and 33 metastases confirmed by imaging follow-up in the 1-day protocol while 15 primary tumors confirmed by pathology and 54 metastases confirmed by imaging follow-up in the 2-day protocol. 68 Ga-DOTATATE and 18 F-FDG dual-tracer PET imaging revealed the NET tumor heterogeneity in a broader scope than the limited sampling of biopsy. However, the choice of 1-day or 2-day protocol should be considered based on clinical situation. Many studies have already confirmed the value of dual-tracer PET in NENs. Paiella et al. found that in pancreatic NENs, the combined lesion detection rate of 68 Ga-DOTATATE and 18 F-FDG PET/CT was higher than that of single-tracer PET/CT. ( 7 ) In this study, 18 F-FDG PET did not provide additional lesion detection, which may be attributed to the small sample size in this study and variations in study populations across different researches. Hayes et al. proposed a dual-tracer classification served as an independent predictor of overall survival (OS) in patients with gastrointestinal pancreatic-NENs (GEP-NENs): D1 ( 68 Ga-DOTATATE positive/ 18 F-FDG negative), D2 ( 68 Ga-DOTATATE positive/ 18 F-FDG positive), and D3 ( 68 Ga-DOTATATE negative/ 18 F-FDG positive). Patients classified as D1 had a significant longer OS compared to D3, and the dual-tracer classification distributed across G1, G2 and G3 NETs. ( 8 ) Similarly, a study on 18 F-FDG PET/CT for G1 GEP-NEN patients reported that 49% of the patients showed positive 18 F-FDG PET images. ( 9 ) In our study, 9 G1 and 2 G2 primary tumors and 57 metastases were 68 Ga-DOTATATE positive and 18 F-FDG negative, while 5 G1, 9 G2 and 1 NEC primary tumors and 12 metastases were 68 Ga-DOTATATE positive and 18 F-FDG positive. NENs typically exhibit intertumoral and intratumoral heterogeneity, which may limit the accuracy of pathology diagnosis because of the sampling bias from biopsy site. In addition, 18 F-FDG uptake is not solely dependent on proliferation or grading but is influenced by various factors, such as tumor hypoxia, the degree of neovascularization, and the activation of oncogenic pathway and so on, which are all associated with aggressiveness of NENs. ( 10 ) In a dual-tracer PET/CT study, among patients who initially underwent only 68 Ga-DOTATATE PET/CT, 42.5% experienced a change in treatment strategy after additional 18 F-FDG PET/CT ( 11 ), also highlighting the heterogeneity of NENs and the value of dual-tracer PET as an imaging biomarker to supplement the prognostication and treatment guidance of NENs. In summary, dual-tracer PET imaging is helpful for NENs patients, as it provides a more comprehensive evaluation of tumors in a large field than pathology while meeting the needs of integrated diagnosis and treatment, as well as assessing patient prognosis. However, the standard 2-day protocol increases time cost, which may affect patient compliance and potentially delay treatment. Previous studies have confirmed the feasibility of the one-stop 18 F-FDG and 68 Ga-DOTA-FAPI-04 PET/CT imaging using dual‑low activity in patients with malignancies, providing support for exploring dual-tracer PET protocol in this study. ( 12 , 13 ) Notably, although no significant difference was observed in the lesion detection between the 1-day and 2-day protocol cohorts in this study, the 1-day protocol has the advantage of integrating the two tracers, potentially improving lesion detection efficiency. Moreover, compared to PET/CT, PET/MR offers advantages such as higher soft tissue resolution and the absence of CT radiation. In a study by Beiderwellen et al., 8 patients (including 5 patients with GEP-NENs) underwent 68 Ga-DOTATOC PET/MR and PET/CT. The results indicated that PET/MR identified more NENs patients and demonstrated better potential for detecting abdominal lesions compared to PET/CT. ( 14 ) Flechsig et al. found that the combination of 68 Ga-DOTATOC PET and non-contrast-enhanced MRI is the optimal method for assessing liver metastases in GEP-NENs. ( 15 ) Overall, exploring the feasibility of a 1-day dual-tracer PET/MR protocol in NENs is essential. It is worth noting that in the 2-day protocol, the 18 F-FDG PET/MR scan includes a dedicated abdomen-pelvis scan which are not performed in the 1-day protocol, thus provides 18 F-FDG PET images with higher counting rate, extra T2 FS images, and fusion images of 18 F-FDG PET and T2 FS images. These additional images may enhance lesion conspicuity and characterization, as well as anatomical-functional correlation, especially for small lesions like liver metastasis from NENs or those located in organs with substantial physiological variation, such as GEP-NENs. Thus, the choice of protocol should be individualized based on clinical circumstances. This study had some limitations. First, it was a single-center retrospective study with a small sample size, and therefore was not sufficient to explore the potential value of dual-tracer integration in the 1-day protocol for NENs or analysis the diagnostic confidence in NEC subgroup, as mentioned above. In this study, diagnostic confidence in 18 F-FDG PET images for G2 NETs was slightly higher in the 1-day protocol cohort than in the 2-day protocol cohort. This result may also be attributed to the small sample size. Secondly, in the 1-day protocol, 68 Ga-DOTATATE could potentially influence 18 F-FDG PET/MR imaging. However, the interval between 68 Ga-DOTATATE injection and 18 F-FDG PET/MR scanning was approximately 5.5 hours. Considering the half-life and pharmacokinetics of 68 Ga-DOTATATE, ( 16 ) this effect could be considered negligible. Conclusion In patients with NENs, the 1-day 68 Ga-DOTATATE and 18 F-FDG PET/MR imaging with dual-low-activity is feasible and provides equivalent lesion detection and diagnostic confidence compared to the 2-day protocol. Declarations Acknowledgements: Not applicable. Funding: This study is supported by the Innovative Medical Device Application Demonstration Program of Shanghai Municipal Commission of Economy and Informatization (grant number: 23SHS01200), the Key Program of Ministry of Industry and Information Technology of China (CEIEC-2022-ZM02-0219), the Chinese National Key Clinical Specialty Program (grant number: YWP2022-007), National High-End Medical Equipment Popularization and Application Program (2024TGYY06). Conflicts of interest: The authors declare that they have no conflict of interest with regard to this study. Ethical approval: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Data Availability: All research data and computer codes are available from the corresponding author upon request. 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Eur J Nucl Med Mol Imaging 50(8):2271–2281 Zheng Z, He Y, Mao W, Yu H, Wu H, Yang R et al (2025) Exploration the feasibility and additional value of [(18)F]FDG/[(68)Ga]Ga-FAPI-04 dual-low-activity-tracer one-stop total-body PET imaging at 34 min post-injection of [(68)Ga]Ga-FAPI-04. Eur J Nucl Med Mol Imaging 52(2):638–647 Beiderwellen KJ, Poeppel TD, Hartung-Knemeyer V, Buchbender C, Kuehl H, Bockisch A et al (2013) Simultaneous 68Ga-DOTATOC PET/MRI in patients with gastroenteropancreatic neuroendocrine tumors: initial results. Invest Radiol 48(5):273–279 Flechsig P, Zechmann CM, Schreiweis J, Kratochwil C, Rath D, Schwartz LH et al (2015) Qualitative and quantitative image analysis of CT and MR imaging in patients with neuroendocrine liver metastases in comparison to (68)Ga-DOTATOC PET. Eur J Radiol 84(8):1593–1600 Ding W, Yu J, Zheng C, Fu P, Huang Q, Feng DD et al (2022) Machine Learning-Based Noninvasive Quantification of Single-Imaging Session Dual-Tracer (18)F-FDG and (68)Ga-DOTATATE Dynamic PET-CT in Oncology. IEEE Trans Med Imaging 41(2):347–359 Cite Share Download PDF Status: Published Journal Publication published 12 Feb, 2026 Read the published version in Molecular Imaging and Biology → Version 1 posted Editorial decision: Minor revisions 22 Oct, 2025 Reviewers agreed at journal 02 Oct, 2025 Reviewers invited by journal 02 Oct, 2025 Editor assigned by journal 29 Sep, 2025 First submitted to journal 25 Sep, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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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-7718410","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":523665787,"identity":"d1c399bf-9596-46f6-b14b-28e8e9b981f2","order_by":0,"name":"Wenjin Zhao","email":"","orcid":"","institution":"Zhongshan Hospital Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Wenjin","middleName":"","lastName":"Zhao","suffix":""},{"id":523665788,"identity":"1466d0ae-b40c-4d18-8af4-e8e4970fdc28","order_by":1,"name":"Lifang Pang","email":"","orcid":"","institution":"Zhongshan Hospital Fudan 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1","display":"","copyAsset":false,"role":"figure","size":200943,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eProcess of the patient recruitment. \u003c/strong\u003eNEN, neuroendocrine neoplasms.\u003c/p\u003e","description":"","filename":"Fig1.png","url":"https://assets-eu.researchsquare.com/files/rs-7718410/v1/53ca4281e5cfa2ba5f31cbd2.png"},{"id":93616452,"identity":"db577870-80e6-47f8-a9ac-08ed6a5eb17c","added_by":"auto","created_at":"2025-10-15 17:00:29","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":233579,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eImaging protocol diagram. (a)\u003c/strong\u003eDiagram of the 1-day protocol. \u003cstrong\u003e(b)\u003c/strong\u003e Diagram of the 2-day protocol.AC, attenuation correction; EPI-DWI, echo planar imaging-diffusion weighted imaging; FS, fat suppression; FSE, fast spin echo; RG, respiratory gating.\u003c/p\u003e","description":"","filename":"Fig2.png","url":"https://assets-eu.researchsquare.com/files/rs-7718410/v1/b716f5f98420d0021540a8c0.png"},{"id":93616450,"identity":"af96a321-b45b-4e1d-8cf3-f827b8ac57e1","added_by":"auto","created_at":"2025-10-15 17:00:29","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":773994,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eThe smallest and lowest \u003c/strong\u003e\u003csup\u003e\u003cstrong\u003e68\u003c/strong\u003e\u003c/sup\u003e\u003cstrong\u003eGa-DOTATATE uptake lesions detected by the 1-day and 2-day protocol. (a-d)\u003c/strong\u003e show the smallest lesion (white arrow) detected by the 1-day protocol, a 2 mm liver metastasis in a patient with G2 duodenal NET. The lesion exhibited mild \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE uptake \u003cstrong\u003e(a)\u003c/strong\u003e and high signal intensity on T2 FS \u003cstrong\u003e(c)\u003c/strong\u003e and DWI \u003cstrong\u003e(d)\u003c/strong\u003e images. \u003cstrong\u003e(e-h)\u003c/strong\u003e show the lesion (white circle) with the lowest \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE uptake in the 1-day protocol, a primary tumor in the same G2 rectal NET patient from Figure 4, with an SUV\u003csub\u003emax\u003c/sub\u003e of 2.9. The lesion exhibited mild \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE uptake \u003cstrong\u003e(e)\u003c/strong\u003e, isointensity on T2 FS \u003cstrong\u003e(g)\u003c/strong\u003e images, and high signal intensity on DWI \u003cstrong\u003e(h)\u003c/strong\u003e images. I-L show the smallest lesion (white triangle) detected by the 2-day protocol, a 2.6 mm liver metastasis in the same patient from Figure 5 with G2 rectal NET. The lesion exhibited mild \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE uptake \u003cstrong\u003e(i)\u003c/strong\u003e and high signal intensity on T2 FS \u003cstrong\u003e(k)\u003c/strong\u003e and DWI \u003cstrong\u003e(l)\u003c/strong\u003e images. M-P show the lesion (white rectangle) with the lowest \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE uptake in the 2-day protocol, a lymph node metastasis in another G2 rectal NET patient with an SUV\u003csub\u003emax\u003c/sub\u003e of 0.5. The lesion exhibited no \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE uptake \u003cstrong\u003e(m)\u003c/strong\u003e, high signal intensity on T2 FS \u003cstrong\u003e(k)\u003c/strong\u003e and DWI \u003cstrong\u003e(p)\u003c/strong\u003e images. All fusion images \u003cstrong\u003e(b, f, j, n)\u003c/strong\u003e were generated by combining \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET images with T2 FS images. DWI, diffusion weighted imaging; FS, fat suppression; NET, neuroendocrine tumor; SUV\u003csub\u003emax\u003c/sub\u003e, maximum standard uptake value.\u003c/p\u003e","description":"","filename":"Fig3.png","url":"https://assets-eu.researchsquare.com/files/rs-7718410/v1/d7849ad919aee8312cdfc409.png"},{"id":93616453,"identity":"7908a02c-519c-4fbd-8819-e46bb6cc7c06","added_by":"auto","created_at":"2025-10-15 17:00:29","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":627701,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePET/MR images of a patient from the 1-day protocol cohort.\u003c/strong\u003e A 53-year-old female diagnosed with G1 rectal NET by pathology. The primary tumor (red arrow) demonstrates mild uptake of \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE \u003cstrong\u003e(b)\u003c/strong\u003e and slight uptake of \u003csup\u003e18\u003c/sup\u003eF-FDG \u003cstrong\u003e(f)\u003c/strong\u003e, along with slightly high signal intensity on T2 FS \u003cstrong\u003e(d)\u003c/strong\u003e and isointense on T1 images \u003cstrong\u003e(h)\u003c/strong\u003e. The short diameter of the primary tumor was 10.8 mm, and the SUV\u003csub\u003emax\u003c/sub\u003e on the \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET and \u003csup\u003e18\u003c/sup\u003eF-FDG PET was 2.9 and 3.3, respectively. The fusion images \u003cstrong\u003e(c, g)\u003c/strong\u003e were respectively generated by combining \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET with T2 FS images, and \u003csup\u003e18\u003c/sup\u003eF-FDG PET with T1 images. FS, fat suppression; NET, neuroendocrine tumor; SUV\u003csub\u003emax\u003c/sub\u003e, maximum standard uptake value.\u003c/p\u003e","description":"","filename":"Fig4.png","url":"https://assets-eu.researchsquare.com/files/rs-7718410/v1/a58a0442fb84272f55ff8935.png"},{"id":93616454,"identity":"c3755609-9a92-4711-b277-bc4721764903","added_by":"auto","created_at":"2025-10-15 17:00:29","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":755014,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePET/MR images of a patient from the 2-day protocol cohort. \u003c/strong\u003eA 55-year-old male diagnosed with G2 rectal NET by pathology. The primary tumor demonstrates (red triangle) significant uptake of \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE \u003cstrong\u003e(a, b)\u003c/strong\u003e, slight uptake of \u003csup\u003e18\u003c/sup\u003eF-FDG \u003cstrong\u003e(e, f)\u003c/strong\u003e, along with high signal intensity on DWI \u003cstrong\u003e(d)\u003c/strong\u003e and T2 \u003cstrong\u003e(h)\u003c/strong\u003e images. The short diameter of the primary tumor was 19.9 mm, and the SUV\u003csub\u003emax\u003c/sub\u003e on the \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET and \u003csup\u003e18\u003c/sup\u003eF-FDG PET was 35.3 and 3.2, respectively. The fusion images \u003cstrong\u003e(c, g)\u003c/strong\u003e were respectively generated by combining \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET with DWI images, and \u003csup\u003e18\u003c/sup\u003eF-FDG PET with T2 images. DWI, diffusion weighted imaging; FS, fat suppression; NET, neuroendocrine tumor; SUV\u003csub\u003emax\u003c/sub\u003e, maximum standard uptake value.\u003c/p\u003e","description":"","filename":"Fig5.png","url":"https://assets-eu.researchsquare.com/files/rs-7718410/v1/86bfed1f6c448f0297bd5714.png"},{"id":102785468,"identity":"4d752317-1f25-4fa4-a0cc-e35af947684e","added_by":"auto","created_at":"2026-02-16 16:07:08","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4082520,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7718410/v1/a14f06db-a165-4b11-b040-21e4bd5f43dd.pdf"}],"financialInterests":"","formattedTitle":"\u003cp\u003eExploration of the Feasibility of One-day Dual-low-activity \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and 18F-FDG PET/MR in Patients with Neuroendocrine Neoplasms\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eNeuroendocrine neoplasms (NEN) are a highly heterogeneous group of neoplasms, classified into neuroendocrine tumor (NET) G1, G2, G3 and neuroendocrine carcinoma (NEC) based on cellular morphology and Ki-67 proliferation index. Most well-differentiated NENs exhibit overexpression of somatostatin receptors (SSTRSs), providing a specific target for molecular imaging techniques utilizing somatostatin analogs. (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET imaging, based on SSTRS analogs, is currently a preferred imaging modality for patients with suspected NENs, offering high specificity and sensitivity. (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e) Besides, \u003csup\u003e18\u003c/sup\u003eF-FDG PET, widely used in the imaging of malignant tumors, has demonstrated increasing value in poorly differentiated NENs with low SSTRS expression. A positive \u003csup\u003e18\u003c/sup\u003eF-FDG PET imaging often indicates a more aggressive tumor phenotype and is associated with a poorer patient prognosis. (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e) Consequently, dual-tracer PET using both \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG has gained increasing attention for its potential value in NENs. For instance, Kayani et al. found that combining \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT provided a better assessment of intermediate- and high-grade NENs. (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e) Zhou et al. revealed that diverse uptake patterns of \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG in newly diagnosed NENs was significantly associated with progression-free survival. (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e) However, most previous studies employed a 2-day PET protocol, which increased time cost. What\u0026rsquo;s more, while PET/MR has been increasingly applied in oncology in recent years due to its lower radiation dose and superior soft tissue resolution, the efficiency of dual-tracer PET/MR imaging in NENs remains unreported.\u003c/p\u003e\u003cp\u003eTherefore, the aim of this study was to validate the feasibility of 1-day \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG PET/MR imaging with dual-low-activity compared with 2-day protocol.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eStudy population\u003c/h2\u003e\u003cp\u003eThis single-center retrospective study was approved by our institution\u0026rsquo;s ethics committee (No. B2025-175R). Informed written consent was obtained from each patient. Patients with NENs who underwent 1-day dual-low-activity \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG PET/MR imaging, hereafter referred to as the 1-day protocol, at our hospital between February and July 2024 were reviewed. Fourteen patients with NENs confirmed by pathology performed 1-day protocol were included. Then, another 14 patients with NENs underwent regular-activity \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG PET/MR imaging on separate days, hereafter referred to as the 2-day protocol, were included as control. These patients were matched to the 1-day protocol cohort based on pathology. The patient recruitment process is shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003ePatient preparation and injection\u003c/h3\u003e\n\u003cp\u003eIn the 2-day protocol, the \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE (2.00 MBq/kg) and \u003csup\u003e18\u003c/sup\u003eF-FDG (3.70 MBq/kg) PET/MR scan were performed on two separate days, and were both performed about 1 hour after radiotracer injection.\u003c/p\u003e\u003cp\u003eIn the 1-day protocol, patients first underwent \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE (1.33 MBq/kg) PET/MR scan about 1 hour after the injection, followed by \u003csup\u003e18\u003c/sup\u003eF-FDG (1.85 MBq/kg) PET/MR scan about 1 hour after the injection.\u003c/p\u003e\u003cp\u003eAll patients were required to fast for at least 6 hours before the \u003csup\u003e18\u003c/sup\u003eF-FDG injection with blood glucose not exceeding 11 mmol/L.\u003c/p\u003e\n\u003ch3\u003ePET/MR protocol\u003c/h3\u003e\n\u003cp\u003eThe dual-tracer PET/MR (United Imaging Healthcare Co.Limited, Shanghai, China) scan included a whole-body scan and then a dedicated abdomen-pelvis scan with respiratory gating PET and MRI acquisition at the same time for each tracer. The whole-body PET/MR scan consisted of 5 beds, each involving a 3-minute PET acquisition and a 2-sequence MRI acquisition: 3D Dixon-based T1 water-fat imaging (WFI) sequence for attenuation correction and axial T2 single-shot fast-spin-echo (SSFSE) sequence. The dedicated abdomen-pelvis PET/MR scan include a 15-minute PET acquisition for abdomen and a 10-minute PET acquisition for pelvis, including 3D T1 WFI, axial and coronal T2 fat suppression (FS)-FSE and axial echo planar imaging-diffusion weighted imaging (EPI-DWI) sequence for each bed.\u003c/p\u003e\u003cp\u003eIn the 1-day protocol, the dedicated abdomen-pelvis scan was omitted from the \u003csup\u003e18\u003c/sup\u003eF-FDG PET/MR scan. In the 2-day protocol, the EPI-DWI sequence was omitted from the \u0026sup1;⁸F-FDG PET/MR scan. The two protocols are illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, and the detailed information about the MRI sequences is provided in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eMRI sequence parameters\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eParameter\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eT1 WFI\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eT2 SSFSE\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eT2 FS-FSE\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eEPI-DWI\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eImaging plane\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3D\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAxial\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAxial/coronal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eAxial\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVoxel size, mm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1.52\u0026times;1.37\u0026times;4.00\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.79\u0026times;1.34\u0026times;6.00\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.58\u0026times;1.19\u0026times;6.00\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2.97\u0026times;2.97\u0026times;6.00\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRepetition time, ms\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4.94\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1100\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3500/4000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e4000\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEcho time, ms\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e82.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e99.32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e66.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFlip angle, degrees\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e160\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e90\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e90\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSection thickness, mm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eField of view, mm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e350\u0026times;500\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e450\u0026times;320\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e380\u0026times;300\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e380\u0026times;300\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIntersection gap\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e/\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e20%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e20%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo. of signals acquired\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e/\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eReceiver bandwidth, Hz\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1080\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e500\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e700\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2100\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eb value, mm/s\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e/\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e/\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e/\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e50, 800\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eScan time, s\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e141\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e32, 47, 52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e84, 96\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e212\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRespiratory gating\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e+\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e+\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e+\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e+\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003eEPI-DWI, echo planar imaging-diffusion weighted imaging; FS-FSE, fat suppression fast-spin-echo; SSFSE, single-shot fast-spin-echo; WFI, water-fat imaging.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\n\u003ch3\u003eImaging analysis\u003c/h3\u003e\n\u003cp\u003eTwo nuclear medicine physicians (H.G. and Y.X.) independently analyzed all patient images in random order, assessing lesion detection, diagnostic confidence, and tracer uptake heterogeneity. Both were blinded to clinical data. In cases of disagreement between the two physicians, consensus was reached through discussion.\u003c/p\u003e\u003cp\u003eA lesion took up any radiotracer beyond the adjacent normal tissue was considered detected on PET images. On MRI, a lesion was considered detected if it displayed a signal different from adjacent tissue on any sequence. In PET/MR images, a lesion was considered detected if its tracer uptake exceeded that of adjacent normal tissue on PET, or if an abnormal signal was present in the corresponding area on any MRI sequence. For organs with multiple metastases, two nuclear medicine physicians (L.P. and W.Z.) jointly selected up to 10 lesions per organ: the five with the lowest \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE uptake on dedicated abdomen-pelvis PET images and the five with the smallest short-axis diameter on FS-FSE T2WI.\u003c/p\u003e\u003cp\u003eDiagnostic confidence for all selected lesions was independently assessed on \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET, \u003csup\u003e18\u003c/sup\u003eF-FDG PET, and PET/MR images using a 5-point Likert scale (1-not at all confident, 2-not very confident, 3-neutral, 4-confident, 5-very confident). For PET images, higher tracer uptake in a lesion was considered to correspond to greater diagnostic confidence. For MRI images, more pronounced lesion signal alterations and number of sequences showing these abnormal signals were associated with higher diagnostic confidence. To minimize potential memory effects, diagnostic confidence evaluations of different imaging sets were conducted at 4-week intervals. The evaluation was further subdivided into lesions confirmed by pathology (lesion\u003csub\u003eP\u003c/sub\u003e), lesions confirmed by imaging follow-up (lesion\u003csub\u003eF\u003c/sub\u003e), G1 NETs, G2 NETs and NEC subgroup.\u003c/p\u003e\u003cp\u003eIntra-lesional tumor heterogeneity for lesions confirmed by pathology was evaluated based on the combined uptake patterns of \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG. On each PET scan, lesions with significant tracer uptake (diagnostic confidence score of 4 or 5) were assigned \"++\"; those with mild to moderate uptake (diagnostic confidence score of 2 or 3) were assigned \"+\"; and those with no tracer uptake (diagnostic confidence score of 1) were assigned \"-\"\u003c/p\u003e\u003cp\u003eBesides, spherical volumes of interest (VOI) were drawn around each lesion on \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE dedicated abdomen-pelvis PET images and \u003csup\u003e18\u003c/sup\u003eF-FDG PET images (with VOI drawn on whole-body PET images for the 1-day protocol and on abdomen-pelvis PET images for the 2-day protocol), with the maximum standard uptake value (SUV\u003csub\u003emax\u003c/sub\u003e) automatically calculated.\u003c/p\u003e\u003cp\u003e\u003cem\u003eReference standard\u003c/em\u003e\u003c/p\u003e\u003cp\u003ePrimary tumors were confirmed by pathology. For metastases that could not be confirmed by pathology due to ethical considerations, a diagnosis of malignancy was established based on follow-up contrast-enhanced CT or MRI, with a minimum follow-up period of 2 months.\u003c/p\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003eStatistical analysis\u003c/h2\u003e\u003cp\u003eAll statistical analyses were performed using SPSS (version 22.0; IBM SPSS Inc., IL, USA). The normality of continuous variables was tested using the Kolmogorov-Smirnov test and Shapiro-Wilk test as appropriate. The homogeneity of variance was tested using the Levene test. Continuous variables are presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation or median and interquartile range as appropriate. Categorical variables are represented by absolute values and percentages. The means of variables with normal continuous distributions and the medians of variables with non-normal continuous distributions in two cohorts were compared using the two independent-sample t-test and the Mann-Whitney U test, respectively. The categorical variables were compared using the Fisher\u0026rsquo;s exact test. A \u003cem\u003eP\u003c/em\u003e value\u0026thinsp;\u0026lt;\u0026thinsp;.05 indicated a statistically significant difference.\u003c/p\u003e\u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 14 patients with NENs were included in the 1-day protocol cohort, and another 14 pathologically matched patients were included in the 2-day protocol cohort.\u003c/p\u003e\n\u003ch3\u003eBasic information\u003c/h3\u003e\n\u003cp\u003eThe patient information is presented in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. No significant differences were observed between the 1-day and the 2-day protocol cohort in terms of age, sex, BMI, or NENs grading (all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eBaseline characteristics of patients\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1-day protocol\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2-day protocol\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(N\u0026thinsp;=\u0026thinsp;14)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(N\u0026thinsp;=\u0026thinsp;14)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex, male\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e12(85.71%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e9(64.29%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.385\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge, year\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e53.00\u0026thinsp;\u0026plusmn;\u0026thinsp;12.21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e54.50\u0026thinsp;\u0026plusmn;\u0026thinsp;10.88\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.270\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBMI, kg/m\u0026sup2;\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e24.74\u0026thinsp;\u0026plusmn;\u0026thinsp;2.89\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e24.61\u0026thinsp;\u0026plusmn;\u0026thinsp;2.63\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.868\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTracer dose, MBq\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6.01\u0026thinsp;\u0026plusmn;\u0026thinsp;0.92\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e11.52\u0026thinsp;\u0026plusmn;\u0026thinsp;1.29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePathological diagnosis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eG1 duodenal NET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eG1 rectal NET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eG1 pancreatic NET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eG2 gastric NET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eG2 duodenal NET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eG2 rectal NET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eG2 pancreatic NET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePancreatic NEC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003eValues are absolute value (percentage) or mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation. BMI, body mass index; NEC, neuroendocrine carcinoma; NET, neuroendocrine tumor.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eIn the 1-day protocol cohort, a total of 40 lesions were included. Among them, 13 primary tumors in 14 patients were confirmed by pathology (one patient had two primary tumors, and 2 patients had undergone surgical resection of primary tumors prior to PET/MR imaging). These 2 patients also underwent liver biopsy, which confirmed that the hepatic lesions were metastases originating from the resected primary tumors. In addition, 2 lymph node metastases and 25 distant metastases, both confirmed by imaging follow-up. In the 2-day protocol cohort, a total of 66 lesions in 14 patients were included. Among of them, 15 primary tumors confirmed by pathology (2 patients each had two primary tumors, and 1 patient had undergone surgical resection of the primary tumor prior to PET/MR imaging), 14 lymph node metastases and 37 distant metastases, both confirmed by imaging follow-up.\u003c/p\u003e\n\u003ch3\u003eLesion detection\u003c/h3\u003e\n\u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, no significant differences were observed between the two cohorts in the lesion detection rates or short-axis diameter. The 1-day protocol detected 39 out of 40 lesions, while the 2-day protocol detected 65 out of 66 lesions. In the 1-day protocol cohort, the detected smallest lesion was a 2.0 mm diameter liver metastasis in a patient with G2 duodenal NET (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eA-C), and the lowest \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE uptake lesion was a primary tumor with SUV\u003csub\u003emax\u003c/sub\u003e of 2.91 in a patient with G1 rectal NET (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eD-F). In the 2-day protocol cohort, the detected smallest lesion was a 2.6 mm diameter liver metastasis in a patient with G2 rectal NET (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eG-I), and the lowest \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE uptake lesion was a lymph node metastasis with SUV\u003csub\u003emax\u003c/sub\u003e of 0.54 in a patient with G2 rectal NET, identified through MRI images (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eJ-L). Both protocols failed to detect one G1 rectal primary tumor. Furthermore, for the lesion\u003csub\u003eP\u003c/sub\u003e and lesion\u003csub\u003eF\u003c/sub\u003e subgroups, lesion detection rates did not show any significant differences between protocols (all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparisons of the lesion detection between 1-day and 2-day protocol cohort\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1-day protocol\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2-day protocol\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAll lesions\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e39(97.50%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e65(98.48%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.000\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eShort-axis diameter, mm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6.7(3.3\u0026ndash;10.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.4(3.9\u0026ndash;10.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.877\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e8.2\u0026thinsp;\u0026plusmn;\u0026thinsp;6.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e9.2\u0026thinsp;\u0026plusmn;\u0026thinsp;9.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSUV\u003csub\u003emax\u003c/sub\u003e\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003csup\u003e68\u003c/sup\u003eGa-DOTATATE\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5.1(4.0-19.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e9.2(5.4\u0026ndash;27.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.049\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e17.1\u0026thinsp;\u0026plusmn;\u0026thinsp;25.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e20.6\u0026thinsp;\u0026plusmn;\u0026thinsp;25.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003csup\u003e18\u003c/sup\u003eF-FDG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3.0(2.4-4.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.5(1.2-2.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3.8\u0026thinsp;\u0026plusmn;\u0026thinsp;3.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.4\u0026thinsp;\u0026plusmn;\u0026thinsp;3.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLesions\u003csub\u003eP\u003c/sub\u003e\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e12(92.31%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e14(93.33%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.000\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eShort-axis diameter, mm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10.3(8.1\u0026ndash;14.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e14.6(9.1\u0026ndash;21.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.231\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e12.0\u0026thinsp;\u0026plusmn;\u0026thinsp;5.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e18.0\u0026thinsp;\u0026plusmn;\u0026thinsp;13.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSUV\u003csub\u003emax\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003csup\u003e68\u003c/sup\u003eGa-DOTATATE\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e16.0(4.8\u0026ndash;47.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e29.8(20.4\u0026ndash;35.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.252\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e34.2\u0026thinsp;\u0026plusmn;\u0026thinsp;39.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e42.0\u0026thinsp;\u0026plusmn;\u0026thinsp;38.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003csup\u003e18\u003c/sup\u003eF-FDG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4.2(3.0-6.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.9(1.2\u0026ndash;3.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.020\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5.9\u0026thinsp;\u0026plusmn;\u0026thinsp;5.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLesions\u003csub\u003eF\u003c/sub\u003e\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e27(100%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e51(100%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eN/A\u003csup\u003e4\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eShort-axis diameter, mm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4.2(3.0-9.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4.7(3.9\u0026ndash;6.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.401\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6.6\u0026thinsp;\u0026plusmn;\u0026thinsp;5.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.8\u0026thinsp;\u0026plusmn;\u0026thinsp;5.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSUV\u003csub\u003emax\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003csup\u003e68\u003c/sup\u003eGa-DOTATATE\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5.1(3.8\u0026ndash;15.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7.1(5.1\u0026ndash;18.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.052\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e9.5\u0026thinsp;\u0026plusmn;\u0026thinsp;8.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e14.7\u0026thinsp;\u0026plusmn;\u0026thinsp;16.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003csup\u003e18\u003c/sup\u003eF-FDG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.7(2.3\u0026ndash;3.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.5(1.2\u0026ndash;1.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.9\u0026thinsp;\u0026plusmn;\u0026thinsp;0.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003eValues are absolute value (percentage) or median (interquartile range) or mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation.\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003e1. SUV\u003csub\u003emax\u003c/sub\u003e indicates maximum standard uptake value\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003e2. Lesions\u003csub\u003eP\u003c/sub\u003e indicates lesions confirmed by pathology\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003e3. Lesions\u003csub\u003eF\u003c/sub\u003e indicates lesions confirmed by imaging follow-up\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003e4. N/A indicates not applicable\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003eDiagnostic confidence\u003c/h2\u003e\u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, no significant differences were observed in diagnostic confidence between the 1-day and 2-day protocols for all lesions, lesions\u003csub\u003eP\u003c/sub\u003e, lesion\u003csub\u003eF\u003c/sub\u003e or G2 NETs when evaluating lesions using \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET, \u003csup\u003e18\u003c/sup\u003eF-FDG PET or PET/MR images (all P\u0026thinsp;\u0026gt;\u0026thinsp;0.05). For the G1 NETs subgroup, no significant differences were observed in the diagnostic confidence between cohorts when using \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET or PET/MR images. However, the \u003csup\u003e18\u003c/sup\u003eF-FDG PET diagnostic confidence was slightly higher in the 1-day protocol cohort than in the 2-day protocol cohort. Since only one NEC lesion was presented in the 1-day protocol, statistical analysis was not performed.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparisons of the diagnostic confidence between 1-day and 2-day protocol cohort\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"10\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e\u003cp\u003e1-day protocol\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c7\" namest=\"c5\"\u003e\u003cp\u003e2-day protocol\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c10\" namest=\"c8\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDOTATATE PET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eFDG PET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePET/MR\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eDOTATATE PET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eFDG PET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003ePET/MR\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003eDOTATATE PET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eFDG PET\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003ePET/MR\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAll lesions\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3(\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4(\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" 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colname=\"c9\"\u003e\u003cp\u003e0.188\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.119\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLesions\u003csub\u003eP\u003c/sub\u003e\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2(\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4(\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e5(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.316\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.156\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.185\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLesions\u003csub\u003eF\u003c/sub\u003e\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2(\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4(\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e5(\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.178\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.563\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.231\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eG1 NETs\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e5(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.351\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.016\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.606\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eG2 NETs\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3(\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e5(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3(\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e5(\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.681\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.967\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.337\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNEC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e5(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003eN/A\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eN/A\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"10\"\u003eValues are medians (interquartile range).\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"10\"\u003e1. Lesions\u003csub\u003eP\u003c/sub\u003e indicates lesions confirmed by pathology\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"10\"\u003e2. Lesions\u003csub\u003eF\u003c/sub\u003e indicates lesions confirmed by imaging follow-up\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"10\"\u003e3. N/A indicates not applicable\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003eTumor uptake patterns of the dual tracer\u003c/h2\u003e\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e5\u003c/span\u003e presents the different uptake patterns of \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG in the two cohorts. In the 1-day protocol, 5 G1, 3 G2, 1 NEC primary tumors, 2 lymph node and 2 liver metastases were positive for both \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG PET, 1 G1 pancreatic primary tumor, 2 G2 duodenal primary tumors 1 bone and 19 liver metastases were positive for \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET and negative for \u003csup\u003e18\u003c/sup\u003eF-FDG PET, and 1 G1 rectal primary tumor and 3 liver metastases were negative for both \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG PET. Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e shows PET/MR images of a patient from the 1-day protocol cohort diagnosed with G2 pancreatic NET.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003e\u003cb\u003ea\u003c/b\u003e Different uptake patterns in primary tumors of the both cohorts\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c2\" namest=\"c1\" rowspan=\"2\"\u003e\u003cp\u003e1-day protocol\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e\u003cp\u003eDOTATATE uptake pattern\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eNumber\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(++)\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(+)\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(-)\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eFDG uptake pattern\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(++)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(+)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(-)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eNumber\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c2\" namest=\"c1\" rowspan=\"2\"\u003e\u003cp\u003e2-day protocol\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e\u003cp\u003eDOTATATE uptake pattern\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eNumber\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(++)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(+)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(-)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eFDG uptake pattern\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(++)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(+)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(-)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eNumber\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003e1. ++ indicates lesion presents significant tracer uptake\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003e2. + indicates lesion presents mild to moderate tracer uptake\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003e3. - indicates lesion presents no tracer uptake.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003e\u003cb\u003eb\u003c/b\u003e Different uptake patterns in metastases of the both cohorts\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c2\" namest=\"c1\" rowspan=\"2\"\u003e\u003cp\u003e1-day protocol\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e\u003cp\u003eDOTATATE uptake pattern\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eNumber\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(++)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(+)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(-)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eFDG uptake pattern\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(++)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(+)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(-)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e23\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eNumber\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e27\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c2\" namest=\"c1\" rowspan=\"2\"\u003e\u003cp\u003e2-day protocol\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e\u003cp\u003eDOTATATE uptake pattern\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eNumber\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(++)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(+)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(-)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eFDG uptake pattern\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(++)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(+)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e(-)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e43\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eNumber\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e51\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003e++ indicates lesion presents significant tracer uptake, + indicates lesion presents mild to moderate tracer uptake, - indicates lesion presents no tracer uptake.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eIn the 2-day protocol, 6 G2 primary tumors, 6 lymph node, 1 implantation and 1 liver metastases were positive for both \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG PET, 8 G1 primary tumors, 7 lymph node, 2 bone and 28 liver metastases were positive for \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET and negative for \u003csup\u003e18\u003c/sup\u003eF-FDG PET, and 1 G1 rectal primary tumor, 1 lymph node and 5 liver metastases were negative for both \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG PET. Figure\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e displays PET/MR images of a patient from the 2-day protocol cohort diagnosed with G2 rectal NET.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this study, primary tumors in the 1-day and 2-day protocol cohorts were matched based on pathology diagnosis. No significant differences were found in lesion detection rates or diagnostic confidence between the two cohorts, including 13 primary tumors confirmed by pathology and 33 metastases confirmed by imaging follow-up in the 1-day protocol while 15 primary tumors confirmed by pathology and 54 metastases confirmed by imaging follow-up in the 2-day protocol. \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG dual-tracer PET imaging revealed the NET tumor heterogeneity in a broader scope than the limited sampling of biopsy. However, the choice of 1-day or 2-day protocol should be considered based on clinical situation.\u003c/p\u003e\u003cp\u003eMany studies have already confirmed the value of dual-tracer PET in NENs. Paiella et al. found that in pancreatic NENs, the combined lesion detection rate of \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT was higher than that of single-tracer PET/CT. (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e) In this study, \u003csup\u003e18\u003c/sup\u003eF-FDG PET did not provide additional lesion detection, which may be attributed to the small sample size in this study and variations in study populations across different researches. Hayes et al. proposed a dual-tracer classification served as an independent predictor of overall survival (OS) in patients with gastrointestinal pancreatic-NENs (GEP-NENs): D1 (\u003csup\u003e68\u003c/sup\u003eGa-DOTATATE positive/\u003csup\u003e18\u003c/sup\u003eF-FDG negative), D2 (\u003csup\u003e68\u003c/sup\u003eGa-DOTATATE positive/\u003csup\u003e18\u003c/sup\u003eF-FDG positive), and D3 (\u003csup\u003e68\u003c/sup\u003eGa-DOTATATE negative/\u003csup\u003e18\u003c/sup\u003eF-FDG positive). Patients classified as D1 had a significant longer OS compared to D3, and the dual-tracer classification distributed across G1, G2 and G3 NETs. (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e) Similarly, a study on \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT for G1 GEP-NEN patients reported that 49% of the patients showed positive \u003csup\u003e18\u003c/sup\u003eF-FDG PET images. (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e) In our study, 9 G1 and 2 G2 primary tumors and 57 metastases were \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE positive and \u003csup\u003e18\u003c/sup\u003eF-FDG negative, while 5 G1, 9 G2 and 1 NEC primary tumors and 12 metastases were \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE positive and \u003csup\u003e18\u003c/sup\u003eF-FDG positive. NENs typically exhibit intertumoral and intratumoral heterogeneity, which may limit the accuracy of pathology diagnosis because of the sampling bias from biopsy site. In addition, \u003csup\u003e18\u003c/sup\u003eF-FDG uptake is not solely dependent on proliferation or grading but is influenced by various factors, such as tumor hypoxia, the degree of neovascularization, and the activation of oncogenic pathway and so on, which are all associated with aggressiveness of NENs. (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e) In a dual-tracer PET/CT study, among patients who initially underwent only \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET/CT, 42.5% experienced a change in treatment strategy after additional \u003csup\u003e18\u003c/sup\u003eF-FDG PET/CT (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e), also highlighting the heterogeneity of NENs and the value of dual-tracer PET as an imaging biomarker to supplement the prognostication and treatment guidance of NENs. In summary, dual-tracer PET imaging is helpful for NENs patients, as it provides a more comprehensive evaluation of tumors in a large field than pathology while meeting the needs of integrated diagnosis and treatment, as well as assessing patient prognosis.\u003c/p\u003e\u003cp\u003eHowever, the standard 2-day protocol increases time cost, which may affect patient compliance and potentially delay treatment. Previous studies have confirmed the feasibility of the one-stop \u003csup\u003e18\u003c/sup\u003eF-FDG and \u003csup\u003e68\u003c/sup\u003eGa-DOTA-FAPI-04 PET/CT imaging using dual‑low activity in patients with malignancies, providing support for exploring dual-tracer PET protocol in this study. (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e) Notably, although no significant difference was observed in the lesion detection between the 1-day and 2-day protocol cohorts in this study, the 1-day protocol has the advantage of integrating the two tracers, potentially improving lesion detection efficiency. Moreover, compared to PET/CT, PET/MR offers advantages such as higher soft tissue resolution and the absence of CT radiation. In a study by Beiderwellen et al., 8 patients (including 5 patients with GEP-NENs) underwent \u003csup\u003e68\u003c/sup\u003eGa-DOTATOC PET/MR and PET/CT. The results indicated that PET/MR identified more NENs patients and demonstrated better potential for detecting abdominal lesions compared to PET/CT. (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e) Flechsig et al. found that the combination of \u003csup\u003e68\u003c/sup\u003eGa-DOTATOC PET and non-contrast-enhanced MRI is the optimal method for assessing liver metastases in GEP-NENs. (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e) Overall, exploring the feasibility of a 1-day dual-tracer PET/MR protocol in NENs is essential. It is worth noting that in the 2-day protocol, the \u003csup\u003e18\u003c/sup\u003eF-FDG PET/MR scan includes a dedicated abdomen-pelvis scan which are not performed in the 1-day protocol, thus provides \u003csup\u003e18\u003c/sup\u003eF-FDG PET images with higher counting rate, extra T2 FS images, and fusion images of \u003csup\u003e18\u003c/sup\u003eF-FDG PET and T2 FS images. These additional images may enhance lesion conspicuity and characterization, as well as anatomical-functional correlation, especially for small lesions like liver metastasis from NENs or those located in organs with substantial physiological variation, such as GEP-NENs. Thus, the choice of protocol should be individualized based on clinical circumstances.\u003c/p\u003e\u003cp\u003eThis study had some limitations. First, it was a single-center retrospective study with a small sample size, and therefore was not sufficient to explore the potential value of dual-tracer integration in the 1-day protocol for NENs or analysis the diagnostic confidence in NEC subgroup, as mentioned above. In this study, diagnostic confidence in\u003csup\u003e18\u003c/sup\u003eF-FDG PET images for G2 NETs was slightly higher in the 1-day protocol cohort than in the 2-day protocol cohort. This result may also be attributed to the small sample size. Secondly, in the 1-day protocol, \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE could potentially influence \u003csup\u003e18\u003c/sup\u003eF-FDG PET/MR imaging. However, the interval between \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE injection and \u003csup\u003e18\u003c/sup\u003eF-FDG PET/MR scanning was approximately 5.5 hours. Considering the half-life and pharmacokinetics of \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE, (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e) this effect could be considered negligible.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn patients with NENs, the 1-day \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG PET/MR imaging with dual-low-activity is feasible and provides equivalent lesion detection and diagnostic confidence compared to the 2-day protocol.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u003c/strong\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e This study is supported by the Innovative Medical Device Application Demonstration Program of Shanghai Municipal Commission of Economy and Informatization (grant number: 23SHS01200), the Key Program of Ministry of Industry and Information Technology of China (CEIEC-2022-ZM02-0219), the Chinese National Key Clinical Specialty Program (grant number: YWP2022-007), National High-End Medical Equipment Popularization and Application Program (2024TGYY06).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of interest:\u003c/strong\u003e The authors declare that they have no conflict of interest with regard to this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical approval:\u003c/strong\u003e All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability:\u0026nbsp;\u003c/strong\u003e All research data and computer codes are available from the corresponding author upon request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eReubi JC, Maecke HR (2008) Peptide-based probes for cancer imaging. J Nucl Med 49(11):1735\u0026ndash;1738\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAmbrosini V, Kunikowska J, Baudin E, Bodei L, Bouvier C, Capdevila J et al (2021) Consensus on molecular imaging and theranostics in neuroendocrine neoplasms. Eur J Cancer 146:56\u0026ndash;73\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eEzziddin S, Adler L, Sabet A, P\u0026ouml;ppel TD, Grabellus F, Y\u0026uuml;ce A et al (2014) Prognostic stratification of metastatic gastroenteropancreatic neuroendocrine neoplasms by 18F-FDG PET: feasibility of a metabolic grading system. J Nucl Med 55(8):1260\u0026ndash;1266\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYu R, Wachsman A (2017) Imaging of Neuroendocrine Tumors: Indications, Interpretations, Limits, and Pitfalls. Endocrinol Metab Clin North Am 46(3):795\u0026ndash;814\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKayani I, Bomanji JB, Groves A, Conway G, Gacinovic S, Win T et al (2008) Functional imaging of neuroendocrine tumors with combined PET/CT using 68Ga-DOTATATE (DOTA-DPhe1,Tyr3-octreotate) and 18F-FDG. Cancer 112(11):2447\u0026ndash;2455\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhou Y, Li L, Wang H, Huang HX, Cao D, Ke NW et al (2024) Heterogeneous Uptake of 68 Ga-DOTATATE and 18 F-FDG in Initial Diagnosed Neuroendocrine Tumors Patients: Which Patients Are Suitable for Dual-Tracer PET Imaging? Clin Nucl Med 49(6):516\u0026ndash;520\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePaiella S, Landoni L, Tebaldi S, Zuffante M, Salgarello M, Cingarlini S et al (2022) Dual-Tracer (68Ga-DOTATOC and 18F-FDG-)-PET/CT Scan and G1-G2 Nonfunctioning Pancreatic Neuroendocrine Tumors: A Single-Center Retrospective Evaluation of 124 Nonmetastatic Resected Cases. Neuroendocrinology 112(2):143\u0026ndash;152\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHayes AR, Furtado O'Mahony L, Quigley AM, Gnanasegaran G, Caplin ME, Navalkissoor S et al (2022) The Combined Interpretation of 68Ga-DOTATATE PET/CT and 18F-FDG PET/CT in Metastatic Gastroenteropancreatic Neuroendocrine Tumors: A Classification System With Prognostic Impact. Clin Nucl Med 47(1):26\u0026ndash;35\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMagi L, Prosperi D, Lamberti G, Marasco M, Ambrosini V, Rinzivillo M et al (2022) Role of [(18)F]FDG PET/CT in the management of G1 gastro-entero-pancreatic neuroendocrine tumors. Endocrine 76(2):484\u0026ndash;490\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBinderup T, Knigge U, Johnbeck CB, Loft A, Berthelsen AK, Oturai P et al (2021) (18)F-FDG PET is Superior to WHO Grading as a Prognostic Tool in Neuroendocrine Neoplasms and Useful in Guiding PRRT: A Prospective 10-Year Follow-up Study. J Nucl Med 62(6):808\u0026ndash;815\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMetser U, Nunez JE, Chan D, Kulanthaivelu R, Murad V, Santiago AT et al (2024) Dual Somatostatin Receptor/(18)F-FDG PET/CT Imaging in Patients with Well-Differentiated, Grade 2 and 3 Gastroenteropancreatic Neuroendocrine Tumors. J Nucl Med 65(10):1591\u0026ndash;1596\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLiu G, Mao W, Yu H, Hu Y, Gu J, Shi H (2023) One-stop [(18)F]FDG and [(68)Ga]Ga-DOTA-FAPI-04 total-body PET/CT examination with dual-low activity: a feasibility study. Eur J Nucl Med Mol Imaging 50(8):2271\u0026ndash;2281\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZheng Z, He Y, Mao W, Yu H, Wu H, Yang R et al (2025) Exploration the feasibility and additional value of [(18)F]FDG/[(68)Ga]Ga-FAPI-04 dual-low-activity-tracer one-stop total-body PET imaging at 34 min post-injection of [(68)Ga]Ga-FAPI-04. Eur J Nucl Med Mol Imaging 52(2):638\u0026ndash;647\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBeiderwellen KJ, Poeppel TD, Hartung-Knemeyer V, Buchbender C, Kuehl H, Bockisch A et al (2013) Simultaneous 68Ga-DOTATOC PET/MRI in patients with gastroenteropancreatic neuroendocrine tumors: initial results. Invest Radiol 48(5):273\u0026ndash;279\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFlechsig P, Zechmann CM, Schreiweis J, Kratochwil C, Rath D, Schwartz LH et al (2015) Qualitative and quantitative image analysis of CT and MR imaging in patients with neuroendocrine liver metastases in comparison to (68)Ga-DOTATOC PET. Eur J Radiol 84(8):1593\u0026ndash;1600\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDing W, Yu J, Zheng C, Fu P, Huang Q, Feng DD et al (2022) Machine Learning-Based Noninvasive Quantification of Single-Imaging Session Dual-Tracer (18)F-FDG and (68)Ga-DOTATATE Dynamic PET-CT in Oncology. IEEE Trans Med Imaging 41(2):347\u0026ndash;359\u003c/span\u003e\u003c/li\u003e\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":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"molecular-imaging-and-biology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mibi","sideBox":"Learn more about [Molecular Imaging and Biology](http://link.springer.com/journal/11307)","snPcode":"11307","submissionUrl":"https://www.editorialmanager.com/mibi/default2.aspx","title":"Molecular Imaging and Biology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Dual tracer, 18F-FDG, 68Ga-DOTATATE, NEN, PET/MR","lastPublishedDoi":"10.21203/rs.3.rs-7718410/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7718410/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e\u003cp\u003eThe standard 2-day dual-tracer PET protocol provides more information but is time consuming. Thus, this study aimed to validate the feasibility of 1-day \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG dual-low-activity PET/MR imaging in patient with neuroendocrine neoplasms (NENs).\u003c/p\u003e\u003ch2\u003eProcedures:\u003c/h2\u003e\u003cp\u003eFourteen pairs of NENs patients who underwent 1-day \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG dual-low-activity PET/MR and 2-day \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG PET/MR were retrospectively enrolled. Imaging analysis was performed, including lesion detection rate and diagnostic confidence. Additionally, the diagnostic confidence was also assessed based on \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET, \u003csup\u003e18\u003c/sup\u003eF-FDG PET and PET/MR, respectively.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eThe 1-day protocol detected 39 out of 40 lesions in 14 patients, while the 2-day protocol detected 67 out of 68 lesions in 14 patients. No significant differences were observed in lesion detection (all P\u0026thinsp;\u0026gt;\u0026thinsp;0.05). There was no significant difference in diagnostic confidence between the 1-day protocol and the 2-day protocol for \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE PET (median [IQR]: 3[2\u0026ndash;3] vs. 3[2\u0026ndash;3]), \u003csup\u003e18\u003c/sup\u003eF-FDG PET (1[1\u0026ndash;2] vs. 1[1\u0026ndash;1]), and PET/MR (4[3\u0026ndash;5] vs. 5[4\u0026ndash;5]) in all lesions (all P\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003ethe 1-day \u003csup\u003e68\u003c/sup\u003eGa-DOTATATE and \u003csup\u003e18\u003c/sup\u003eF-FDG dual-low-activity PET/MR imaging protocol in patients with NENs is feasible and provides equivalent lesion detection and diagnostic confidence compared to the 2-day protocol.\u003c/p\u003e","manuscriptTitle":"Exploration of the Feasibility of One-day Dual-low-activity 68Ga-DOTATATE and 18F-FDG PET/MR in Patients with Neuroendocrine Neoplasms","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-15 17:00:24","doi":"10.21203/rs.3.rs-7718410/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Minor revisions","date":"2025-10-22T04:59:18+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2025-10-02T06:59:42+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-02T06:55:47+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-09-29T21:43:13+00:00","index":"","fulltext":""},{"type":"submitted","content":"Molecular Imaging and Biology","date":"2025-09-26T02:37:27+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"molecular-imaging-and-biology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mibi","sideBox":"Learn more about [Molecular Imaging and Biology](http://link.springer.com/journal/11307)","snPcode":"11307","submissionUrl":"https://www.editorialmanager.com/mibi/default2.aspx","title":"Molecular Imaging and Biology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"93b55030-33d0-4e59-8b21-750f2ebca00b","owner":[],"postedDate":"October 15th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-02-16T16:03:23+00:00","versionOfRecord":{"articleIdentity":"rs-7718410","link":"https://doi.org/10.1007/s11307-026-02081-0","journal":{"identity":"molecular-imaging-and-biology","isVorOnly":false,"title":"Molecular Imaging and Biology"},"publishedOn":"2026-02-12 15:58:52","publishedOnDateReadable":"February 12th, 2026"},"versionCreatedAt":"2025-10-15 17:00:24","video":"","vorDoi":"10.1007/s11307-026-02081-0","vorDoiUrl":"https://doi.org/10.1007/s11307-026-02081-0","workflowStages":[]},"version":"v1","identity":"rs-7718410","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7718410","identity":"rs-7718410","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}