Clinical efficacy of MWA via the caudal‒cranial puncture pathway for small hepatocellular carcinoma at the hepatic dome: 3 years of follow-up

Clinical efficacy of MWA via the caudal‒cranial puncture pathway for small hepatocellular carcinoma at the hepatic dome: 3 years of follow-up | 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 Systematic Review Clinical efficacy of MWA via the caudal‒cranial puncture pathway for small hepatocellular carcinoma at the hepatic dome: 3 years of follow-up Wei-Guo Tang, Juan-Juan Xu, Yuan Liu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6213729/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 08 Jan, 2026 Read the published version in BMC Surgery → Version 1 posted 4 You are reading this latest preprint version Abstract Purpose To evaluate the clinical efficacy of microwave ablation (MWA) for small hepatocellular carcinoma (HCC) located at the hepatic dome via the caudal‒cranial direction puncture (CCDPP) within the coronal or sagittal plane under computed tomography (CT) guidance. Methods A retrospective analysis was conducted to analyze data from 29 patients with HCC located at the hepatic dome who underwent CT-guided MWA from March 2019 to November 2024. The puncture path of the microwave antenna during ablation is from caudal to cephalic within the coronal or sagittal planes reconstructed via multislicespiral CT. Baseline patient data were collected, and outcomes, including the puncture technique success rate, ablation success rate, and incidence of complications, were observed. Kaplan‒Meier survival curve analysis was used to calculate the disease-free survival (DFS) and overall survival (OS) rates of all patients. Results The puncture technique and ablation success rates were both 100%, and no serious complications occurred. One month post-MWA, enhanced abdominal CT or MRI scans revealed complete ablation in 96.6% of all patients, whereas 3.4% (1/29) had incomplete ablation, necessitating additional MWA treatment. By the cutoff of follow-up, the mean follow-up time for all patients was 26.03 ± 17.98 months. The local tumor progression rate was 22.7%, and the 1-, 2-, and 3-year disease-free survival rates were 88.1%, 74.2%, and 74.2%, respectively. The 1-, 2-, and 3-year overall survival rates were 91.8%, 72.4%, and 72.4%, respectively. Conclusion Microwave ablation with the CCDPP used in the puncture process is safe, feasible, and effective, with acceptable oncological midterm outcomes for the treatment of small HCC lesions in the hepatic dome. Microwave Ablation Hepatocellular Carcinoma Hepatic Dome Caudal-Cranial direction puncture pathway CT Coronal (Sagittal) Reconstruction Figures Figure 1 Figure 2 Figure 3 Introduction According to data published by the International Agency for Research on Cancer (IARC) in 2020, liver cancer ranks sixth among the most common malignant tumors and is the third leading cause of tumor-related death worldwide[ 1 ]. The annual incidence of hepatocellular carcinoma (HCC) is increasing. The literature reports that only 5–15% of HCC cases are suitable for surgical resection[ 2 ]. Microwave ablation (MWA), known as a thermal ablation technique, offers benefits such as rapid ablation speed, extensive coverage, minimal interference from thermal deposition, and excellent tolerability and repeatability[ 3 , 4 ]. It has become a key treatment modality for HCC, especially for smaller tumor foci, where it shows superior therapeutic efficacy[ 5 ]. While there is a growing body of clinical research on the application of MWA for treating HCC, managing liver tumor lesions located at the hepatic dome remains a great challenge because of factors such as blockage from the ribs and the risk of adjacent tissue (diaphragm or lung) injury. This intricate anatomy complicates the puncture process, increasing the risk of complications, which has long been a significant challenge in liver carcinoma ablation therapy[ 6 ]. The caudal‒cranial direction puncture pathway (CCDPP) is a method that we propose for guiding the puncture process and is much different from the method in the cross-sectional plane normally used in clinical practice. It involves inserting a needle from a point below the plane of the costophrenic angle, pushing the needle from the caudal to cranial direction within the coronal or sagittal plane under CT guidance, and the process of puncture and ablation is finished mainly under the guidance of coronal or sagittal images. The CCDPP may avoid passing through the diaphragm and lungs and decrease the risk of the ablation procedure. In this retrospective study, data were collected and analyzed from 22 patients with HCC lesions located at the hepatic dome at our institution between March 2019 and June 2023 to assess the efficacy, safety and midterm oncological outcome of MWA via the CCDPP for these lesions. Methods General information The Ethics Committee waived formal study approval for this retrospective investigation. All patients provided written consent for the use of their unidentified medical information for research purposes. Between March 2019 and November 2024, 29 patients with HCC lesions at the hepatic dome underwent MWA via the CCDPP. The inclusion criteria were as follows: 1. Pathological or clinical diagnosis of HCC; 2. A single lesion with a maximum diameter of ≤ 5 cm or up to three lesions with a maximum diameter of ≤ 3 cm; 3. Liver function Child‒Pugh class A or B; 4. Tumor lesions located above the plane of the costophrenic angle, with a distance between the edge of the lesion and the diaphragm ≤ 10 mm; 5. The microwave antenna will pass through the diaphragm and lung tissues if puncture is performed within the cross-sectional plane; 6. There was no serious cardiac or pulmonary disease or coagulation disorders. Before ablation treatment, each patient underwent comprehensive laboratory testing, which included routine blood tests, liver and kidney function assessments, coagulation tests, and cardiopulmonary function evaluations. Preprocedural imaging studies included enhanced CT and/or MRI. In addition, after describing the benefits of taking TACE therapy before MWA, some patients chose to receive TACE therapy before MWA therapy. MWA program MWA was performed by two interventional radiologists, each with over five years of MWA experience. A 40-slice spiral CT machine (model U550, united imaging, China) was used for image guidance. The ablation equipment included an MTI-5A MWA system (Nanjing Great Wall Medical Equipment Co., Ltd.), featuring a microwave output frequency of (2450 ± 30) MHz and an adjustable output power range of 0–120 W. A water-cooled circulating MWA antenna with effective lengths of 150 mm, 180 mm, and 210 mm; a diameter of 2 mm; and a microwave emission length of 10 mm was utilized. Ablation was conducted under local anesthesia or sedation with dexmedetomidine (0.5 µg/kg), and patients’ vital signs were continuously monitored. Patients were placed in the supine or prone position on the basis of the lesion's location. A CT scan with a 5-mm layer thickness and 1.0 pitch was performed when respiratory motion was absent. A coronal or sagittal MPR was immediately performed on the postprocessing interface in the CT machine, and a specific CCDPP within the coronal or sagittal plane was planned to ensure that the puncture path could avoid passing through critical anatomical structures such as the diaphragm, lung tissue, kidney and major blood vessels and that most of the pathway remained within the liver parenchyma. After the CCDPP was determined, the puncture point was marked on the body surface, disinfected, and draped. Local anesthesia (2% lidocaine) was administered to the puncture site, after which the microwave ablation needle was inserted through the designated point and pushed following the predetermined CCDPP. After the needle was pushed forward 3–5 cm, another CT scan was performed, and coronal or sagittal images were reconstructed on the postprocessing interface. The angle, position, and depth of the needle were observed and adjusted according to the predetermined CCDPP before further advancing the needle. Once the placement of the ablation needle at the predetermined position within the lesion was confirmed, the microwave ablator was connected, and the ablation parameters were carefully selected according to the size and location of the lesion. The administration of microwave energy will last until the ablated region fully covers the tumor lesion and has at least a 5 mm safety margin. After the ablation procedure, an enhanced CT scan was performed to assess the effectiveness of the treatment. Evaluating whether complete ablation has been achieved is mainly based on coronal or sagittal images. Typically, the ablation region exhibited a low-density region, and if a lesion was fully covered by a low-density region with a safety margin greater than 5 mm, the lesion was considered to be completely ablated. If any residual lesion was identified, the position of the needle tip was adjusted, and the ablation process was repeated. At the end of the procedure, a 10-second needle tract ablation was carried out to prevent tumor implantation and bleeding. After removing the ablation needle, an additional CT scan was performed to confirm the absence of complications such as pneumothorax, pleural effusion, subperitoneal hepatic effusion, and diaphragmatic perforation. After the operation, the patient was placed on bed rest, and vital signs were monitored. The patient also received routine treatments such as liver function protection, hemostasis, and infection prevention. Laboratory examinations, such as liver function tests and routine blood tests, were performed 2 to 3 days postoperation, and the patient was discharged when no abnormalities were found. Observation indicators The success rate of the puncture technique (defined as the number of lesions where the ablation needle successfully punctures the center of the lesion divided by the total number of lesions), the success rate of ablation completion (defined as the number of lesions for which MWA treatment was completed divided by the total number of lesions), and the complication rate were evaluated. The length of the puncture path (defined as the distance from the transcutaneous entry point to the tip of the ablation needle when the tip reaches the lesion) and the number of CT scans (defined as the total number of CT scans per procedure, from the first scan until the lesion was ready for ablation) were recorded. Follow-up One month after the ablation procedure, patients were monitored via enhanced CT or MRI. If a tumor showed hypointense features with no enhancement at any of the three scan phases in the enhanced CT/MRI scan, the efficacy of the lesion was classified as complete ablation (CA). Conversely, if any enhancement was revealed in the tumor region or its edge in the arterial or portal vein phase, the result was classified as incomplete ablation (ICA). For patients with ICA, a repeat MWA procedure may be considered. Subsequent evaluations, including enhanced CT/MRI scans, tumor markers, and other relevant factors, should be conducted every three to six months to monitor tumor progression. Local tumor progression (LTP) was identified by a dispersed, nodular, or irregularly enhanced pattern surrounding the ablation region on contrast-enhanced CT or MR images during follow-up. If LTP is identified during follow-up, the multidisciplinary team will reach a unanimous decision to proceed with further treatment, such as MWA or TACE, on the basis of the CT/MRI assessment of tumor status. The primary follow-up data included disease-free survival (DFS) and overall survival (OS) data. DFS was defined as the period from the day of the MWA procedure to the time of tumor recurrence or death from any cause, whereas OS was defined as the period from treatment initiation to the date of death or the last follow-up visit. Posttreatment lesions were described by imaging according to internationally standardized terminology. At the end of follow-up, all available cross-sectional images after MWA were reviewed to assess the effects on the abdomen. MWA adverse events reported in the book and during postoperative hospitalization were graded according to the Common Terminology Criteria for Adverse Events (CTCAE) v5.0[ 7 ]. Statistical analysis Statistical analysis was conducted via SPSS version 26 (IBM SPSS Statistics). Data are presented as either the mean ± standard deviation or median (range) for continuous variables or as the number and percentage for categorical variables. To compare differences between groups for continuous variables, a t test or the nonparametric Wilcoxon Mann‒Whitney test was used. For qualitative variables, a chi-square test or Fisher’s exact test was employed. Kaplan‒Meier survival curves were used to determine one-, two-, and three-year relapse-free survival rates and overall survival rates, as well as to construct survival curves. Statistical significance was defined as a p value less than 0.05. Results Patient and tumor characteristics A total of 29 lesions from 29 patients with HCC meeting the clinical and pathological diagnosis criteria were included; the maximum diameter of the lesions was 49 mm, with a mean diameter of 25.5 ± 11.0 mm; the distance between the diaphragm and the margins of the lesions was < 5 mm in 65.5% (19/29) of the patients and ≥ 5 mm in 34.5% (10/29) of the patients. The baseline characteristics of the patients are shown in Table 1 . Table 1 Clinical Characteristics (N = 29) Characteristic Value Age(years) Mean 58 Range 45ཞ76 Gender Men 24 Women 5 Etiology of liver disease Hepatitis B virus 15 Hepatitis C virus 1 Other 13 Underlying liver disease Liver cirrhosis 12 Child-Pugh class A 19 Child-Pugh class B 10 TACE 18 Ablation outcome ( one month later ) complete respons 28 partial response 1 Tumor size (mm) Mean ± SD 25.5 ± 11.0 Range 5.0 ~ 49.0 Location the right lobe of liver 26 the left lobe of liver 3 Follow-up time(months) Mean ± SD 26.03 ± 17.98 Range 2 ~ 63 HCC: hepatocellular carcinoma; TACE: transcatheter arterial chemoembolization Technical parameters and efficacy analysis of microwave ablation All 29 lesions were successfully treated via the CCDPP technique, and the success rates for the puncture technique and ablation completion were 100%. The mean puncture path length during ablation was 10.88 ± 1.69 cm, and the average ablation time was 9.63 ± 5.17 minutes. The mean number of CT scans was 9.5 ± 4.9, and the mean total number of CT scans was 24.0 ± 8.6. One month after the MWA procedure, 95.5% (21/22) of all lesions were completely ablated (CA), whereas 4.5% (1/22) remained incompletely ablated (ICA). MWA was performed again on this patient, and complete ablation was achieved after the repeat treatment. (Fig. 1 – 2 ) Complications The pain level varies depending on the location of the lesion during the ablation procedure. The patient complained of pain in the posterior shoulder when the lesion was at the right diaphragmatic apex, whereas discomfort in the precordial region was observed when the lesion was at the left diaphragmatic apex. In this study, the incidence of intraoperative pain was 65.5% (19/29), which was relieved by adjusting the anesthetic dose. Adverse events during intraoperative and postoperative hospitalization were recorded in 21 (72.4%) of the 29 treatments, most of which were CTCAE grade 1 ~ 2 adverse events, including malaise, transient shortness of breath, mild pain or fever, and transient slowing of the heart rate, most of which were self-limiting or disappeared after symptomatic management. No serious complications (≥ CTCAE grade 3), such as pneumothorax, diaphragmatic rupture, hemorrhage, pleural effusion, or biliobronchial fistula, occurred. Survival analysis The mean follow-up of all patients was 26.03 ± 17.98 months. At the end of follow-up, 17.2% (5/29) of the patients experienced local tumor progression. Six patients died during the follow-up period, five after local tumor progression and one from nontumour causes. No tumor needle tract implant metastases were observed. By the end of follow-up, the 1-, 2-, and 3-year disease-free survival rates were 88.1%, 74.2%, and 74.2%, respectively, and the 1-, 2-, and 3-year overall survival rates were 91.8%, 72.4%, and 72.4%, respectively. (Fig. 3 ) Subgroup analysis Comparison between the group with lesion margins ≥ 5 mm away from the diaphragm and the group with margins < 5 mm: the differences in the rates of complete local ablation; 1-, 2-, and 3-year disease-free survival; and 1-, 2-, and 3-year overall survival were not statistically significant. Discussion MWA is a minimally invasive local treatment for early-stage HCC and metastatic liver tumors. Its efficacy has been supported by multiple studies, which indicate that its long-term prognosis is comparable to that of surgery[ 8 – 11 ]. The location of the tumor is a crucial factor influencing local recurrence after percutaneous ablation[ 12 ]. HCC located in the hepatic dome is susceptible to complications, including lung injury, phrenic nerve or diaphragm injury, pneumothorax, and peritoneal burns during the process of puncture and ablation, owing to its proximity to the diaphragm and lung tissue. Therefore, ablating HCC lesions near the diaphragm poses unique challenges. Previous studies have examined various techniques for ablating tumors at the liver apex near the diaphragm, including percutaneous transdiaphragmatic and percutaneous transpulmonary approaches guided by ultrasound or CT imaging. However, these studies reported a high incidence of complications, including hemothorax, pneumothorax, lung injury, and diaphragmatic rupture, with rates reaching 28.6%[ 13 – 15 ]. Other studies concerning conventional cross-sectional puncture and ablation in combination with other methods, such as artificial pleural fluid[ 16 ] and artificial ascites[ 17 , 18 ], or ablations through open surgery or laparoscopic approaches[ 19 , 20 ] have been conducted. However, these methods increase patient suffering, healthcare costs, and the incidence of medically induced or treatment-related adverse effects, resulting in multiple complications. Although in recent years, the development of electromagnetic navigation and image fusion technology can accurately guide the ablation probe puncture into the tumor lesion and improve the puncture operation efficiency, the supporting equipment is expensive and requires additional purchase, which limits the popularity and accessibility of these technologies. Previous studies have described various CT-guided puncture methods for lesions at the top of the hepatic diaphragm, including "craniocaudal tilt"[ 21 ], "angled puncture," "angled approach"[ 22 ], and "nonpleural approach"[ 23 ]. However, few studies have explained the specific procedures of these methods in detail. On the basis of our experience in a single-center setting and a review of the literature, we proposed the CCDPP method and applied it in the clinic. The CCDPP technique involves determining the pathway of the ablation needle in a direction from the caudal to the cranial and determining the extent of the ablation region within the coronal or sagittal plane during the procedure. With the excellent spatial and tissue resolution of the reconstructed coronal or sagittal image, the depth and angle of the ablation needle's entry, the location of the lesion, and the distance between the needle tip and the lesion can be easily visualized, helping the operator exactly adjust the path of the puncture to achieve a successful puncture. The large inclined angle of needle puncture used in the CCDPP reduces the possibility of bleeding by compressing the needle path with the help of the gravity of the upper liver tissue. As the needle is parallel or almost parallel to the diaphragm, this method also has the following advantages: first, it ensures that the needle can pass through normal liver tissue to reach the lesion rather than through the lung or diaphragm, reducing the occurrence of complications such as puncture-related injury of the diaphragm and lung tissue or needle tract bleeding; second, as most lesions are found to grow parallel to the diaphragm, it also ensures that the ablation region and the shape of the tumor match each other very well to achieve appropriate coverage of the ablation region. In addition, the significant improvements in the scanning speed and computing speed of multislice spiral CT have significantly reduced the time delay of the MPR (multiplanar reconstruction) needed for coronal or sagittal images. This makes it technically possible to finish the puncture operation within the coronal or sagittal plane by applying the CCDPP in the ablation of hepatic dome tumors without delay. The majority of hospitals can carry out ablation treatment in this way by using existing CT equipment without increasing the cost of acquiring additional equipment. Nazanin et al. reported an overall success rate of 94% for CT-guided MWA of 48 hepatic fornix tumors, with an average tumor size of 2.2 cm, including patients who underwent successful repeat treatments[ 24 ]. In our study, of the 29 patients treated with ablation via the CCDPP, the success rate for both the puncture technique and ablation completion was 100%, suggesting that the CCDPP is technically applicable in clinical practice. In our study, one-month postoperative follow-up imaging revealed primary complete ablation (CA) in 96.6% (28/29) of the lesions, while the average diameter of the lesions was 25.5 mm, which was greater than those reported in previous studies. Favorable clinical and oncological outcomes in the middle term were also achieved even when the lesion edge was less than 5 mm away from the diaphragm. Teng et al. reported that ablation safety margins less than 5 mm were associated with a higher local tumor progression rate following thermal ablation of HCC, with a 46% risk reduction for each 5 mm increase in the minimum margin size[ 25 ]. It is generally believed that to achieve complete ablation, the ablation boundary typically needs to extend beyond the tumor margin by at least 5 to 10 mm[ 26 ]. However, why is the CA rate comparable to previous findings in this study, even for most lesions < 5 mm away from the diaphragm? The authors believe that the reason is as follows: the needle body of the microwave antenna is parallel to the diaphragm, and the possibility of the microwave antenna working area penetrating the diaphragm for ablation is avoided. If this is the case, catastrophic and severe complications, such as biliary pleural fistula, bronchobiliary fistula or major bleeding, inevitably occur. Typically, in my study, the long axis of the ablation zone was found to be parallel to that of the tumor as well as the diaphragm on coronal or sagittal images. Although the ablation zone touches the diaphragm in a wide basement way, the diaphragm remains undamaged, and exudation in adjacent lungs is also not identified. This makes the operator more conficient when the ablation machine is working and when the ablation is as thorough as possible. Previous studies have reported that local tumor progression (LTP) rates are 5–15.1% for MWA treatment of HCC lesions less than 3 cm in diameter2728(27,28). Several studies have shown that tumor size and inadequate ablation margins are significant factors influencing local tumor progression[ 11 , 29 ]. In this study, LTP was observed in 17.2% (5/29) of the lesions during the follow-up period. The higher rate of LTP in this study than in previous reports may be related to the larger average diameter of the lesions, the small number of patients enrolled, and the longer duration of follow-up. Various studies have confirmed the therapeutic efficacy of TACE-MWA[ 30 , 31 ]. TACE administered before ablation can diminish or obstruct the local blood supply to the tumor, leading to more thorough ablation and a reduced likelihood of local recurrence. This approach also diminishes the heat sink effect and the potential for hematogenous metastasis and implantation metastasis of the tumor during the MWA procedure[ 32 ]. DSA examination has the ability to detect and embolize tiny lesions that may not be discernible through imaging modalities such as ultrasound, CT, and MRI. Additionally, iodine‒oil deposition, which is high density in CT images, serves as a tracer and increases the visibility of tumors on plain CT scans. In our study, 62.1% (18/29) of the patients underwent TACE prior to MWA, accounting for the high complete ablation rate achieved during follow-up. The occurrence of abdominal pain and discomfort following thermal ablation is reported to be 80.1% when the liver cancer lesion is situated below the diaphragm or in close proximity to the hepatic pericardium[ 33 ]. The predominant intraoperative and postoperative complication observed in this patient cohort was pain, predominantly presenting as right upper abdominal discomfort or shoulder pain exacerbated by respiratory movements. Two patients experienced heart rate slowing during the procedure, which improved with intravenous medication, and successfully completed the ablation. Nausea, vomiting, and hypothermia are all common complications after ablation, which may be the response of an organism to visceral nerve reflexes and the stimulation of inflammatory mediators released from necrotic tissues[ 34 , 35 ]. All the apparent complications could be relieved after symptomatic treatment without serious complications such as bleeding, hemothorax, pneumothorax, diaphragm injury, and cholangio-pleural fistula, which indicated that CT-guided MWA via the CCDPP was safe and feasible for the treatment of HCC in the hepatic dome. In conclusion, CT-guided microwave ablation combined with the CCDPP method for the treatment of small HCC at the top of the liver dome did not increase the difficulty of puncture or decrease the technical success rate. Complete ablation could still be achieved even for lesions less than 5 mm away from the diaphragm, indicating that the method is feasible and provides an alternative to solve the problem of puncture access for ablation of liver tumors very close to the diaphragm. However, this study is a single-center retrospective study with a small number of cases, which has limitations, and a multicenter study with a larger sample size and longer follow-up is still warranted to confirm the safety and effectiveness of this method. Declarations Author Contribution T conceived the article; T and X collected the data; T and X, assembled the data; T and L provided the study materials, wrote the manuscript and approved the manuscript. Acknowledgement The authors thank the colleagues in the imaging department for the medical images provided. The author would also like to thank the patient for agreeing to disclose the details of the case for publication. References Sung H, Ferlay J, Siegel RL, et al. 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Zhang YJ, Chen MS, Chen Y, Lau WY, Peng Z. Long-term Outcomes of Transcatheter Arterial Chemoembolization Combined With Radiofrequency Ablation as an Initial Treatment for Early-Stage Hepatocellular Carcinoma. JAMA Netw Open . 2021;4(9):e2126992. Liu C, He J, Li T, Hong D, Su H, Shao H. Evaluation of the efficacy and postoperative outcomes of hydrodissection-assisted microwave ablation for subcapsular hepatocellular carcinoma and colorectal liver metastases. Abdom Radiol . 2021;46(5):2161-2172. Liang P, Wang Y, Yu X, Dong B. Malignant Liver Tumors: Treatment with Percutaneous Microwave Ablation—Complications among Cohort of 1136 Patients. Radiology . 2009;251(3):933-940. Zhou F, Yu X ling, Liang P, et al. Microwave ablation is effective against liver metastases from gastric adenocarcinoma. International Journal of Hyperthermia . Published online March 29, 2017:1-6. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 08 Jan, 2026 Read the published version in BMC Surgery → Version 1 posted Editorial decision: Revision requested 01 Apr, 2025 Editor assigned by journal 27 Mar, 2025 Submission checks completed at journal 27 Mar, 2025 First submitted to journal 12 Mar, 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-6213729","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Systematic Review","associatedPublications":[],"authors":[{"id":433226423,"identity":"559253ff-e652-4291-9d89-442fa8bd7ebd","order_by":0,"name":"Wei-Guo Tang","email":"","orcid":"","institution":"Chengdu University of Traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Wei-Guo","middleName":"","lastName":"Tang","suffix":""},{"id":433226424,"identity":"d390b5a9-f3fa-4c8d-b49d-731bd720d4af","order_by":1,"name":"Juan-Juan Xu","email":"","orcid":"","institution":"Chengdu University of Traditional Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Juan-Juan","middleName":"","lastName":"Xu","suffix":""},{"id":433226425,"identity":"91771d07-c571-497a-9fa8-6bc718aef479","order_by":2,"name":"Yuan Liu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA1UlEQVRIiWNgGAWjYBACPmYog5+ZseHABwYJwlrYYFok25sPPpxBlBYYw+DMsWRjHmIcxsbOY8DM22aXx3Ajx0za5o9FHn8D88NHN/A6DKwluZhxBlBLbptEscQBNmPjHMJamBObJUBaGiQSGw7wsEkToaU+sQ2kxeKPROJ8IrUcTuzhAXqfgU0icQNhLWwFjHPOHU+cwQ4M5N42icSNhwn4hZ//8AaGN2XVifsPA6Pyx5+6xHnHmx8+xqcFCNh/oUYHMw51yIDxBxGKRsEoGAWjYAQDAImWQvVWNq0vAAAAAElFTkSuQmCC","orcid":"","institution":"Department of Interventional Oncology, Hospital of Chengdu University of Traditional Chinese Medicine","correspondingAuthor":true,"prefix":"","firstName":"Yuan","middleName":"","lastName":"Liu","suffix":""}],"badges":[],"createdAt":"2025-03-12 16:23:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6213729/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6213729/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12893-025-03290-0","type":"published","date":"2026-01-08T15:58:50+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":79259734,"identity":"d66c76e0-4fdf-4ce5-afb3-25da85a8e0cc","added_by":"auto","created_at":"2025-03-26 09:21:40","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":96475,"visible":true,"origin":"","legend":"\u003cp\u003ea: A 60-year-old male patient with enhanced MR image suggesting a nodule in segment VII of the right lobe of the liver (white arrow), approximately 24 mm in diameter. The lesion, which was clinically diagnosed as primary HCC, had obvious enhancement in the arterial phase, and its edge was very close to the diaphragm.\u003c/p\u003e\n\u003cp\u003eb: The patient was treated with CT-guided MWA. The microwave antenna was pushed through the narrow gap between the upper pole of the right kidney and the diaphragm and reached the lesion in the sagittal plane via the CCDPP. The body of the microwave antenna is parallel to the diaphragm.\u003c/p\u003e\n\u003cp\u003ec: Enhanced CT after ablation revealed that the long axis of the ablation region (white arrow) was parallel to the diaphragm and close to the diaphragm, with no signs of diaphragm injury, bleeding, or pneumothorax, and the ablation region completely covered the tumor.\u003c/p\u003e\n\u003cp\u003ed: Enhanced MR image of the patient 2 years after the operation showing that the ablation region had further shrunk and that there was no sign of tumor survival.\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6213729/v1/33036648e3b6d9ca2f81fbbe.jpg"},{"id":79260977,"identity":"9b6e2122-7c13-4964-8ecb-ce0a579fd580","added_by":"auto","created_at":"2025-03-26 09:29:40","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":73781,"visible":true,"origin":"","legend":"\u003cp\u003ea, b: A 49-year-old male patient with a diagnosis of HCC. Enhanced CT revealed a nodule in segment VII of the liver, and transverse and sagittal planes revealed that the nodule was broadly basal, with the edges of the lesion being close to the diaphragm.\u003c/p\u003e\n\u003cp\u003ec: The patient was placed in the prone position, and the microwave antennae were punctured in the coronal plane via the CCDPP method. The microwave antennae were parallel to the diaphragm (white arrows) after the antenna was in place and did not penetrate the diaphragm or lung tissue.\u003c/p\u003e\n\u003cp\u003ed: Enhanced CT during ablation revealed that the ablated region was close to the diaphragm and completely covered the tumor while the diaphragm remained intact.\u003c/p\u003e\n\u003cp\u003ee, f: Cross-sectional and sagittal enhanced CT images showing that the ablated region was close to the diaphragm and completely covered the tumor, and no tumor survival was observed 19 months after the operation.\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6213729/v1/1f64ea3089454691421e456b.jpg"},{"id":79259737,"identity":"7af7d03f-c7d1-42a7-a1cb-ea84a709c419","added_by":"auto","created_at":"2025-03-26 09:21:40","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":26640,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Graph showing the overall survival rate. The 1-, 2- and 3-year overall survival rates were 91.8%, 72.4% and 72.4%, respectively. (b) Graph showing disease-free survival. The 1-, 2- and 3-year disease-free survival rates were 88.1%, 74.2% and 74.2%, respectively.\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6213729/v1/9919c7cf7ac9390e35da7162.jpg"},{"id":100069419,"identity":"217cfdd3-d2e4-451c-af6f-632d394ff1bc","added_by":"auto","created_at":"2026-01-12 16:13:46","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":791367,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6213729/v1/dd82013d-23fe-44d5-b199-8cc29d255f73.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Clinical efficacy of MWA via the caudal‒cranial puncture pathway for small hepatocellular carcinoma at the hepatic dome: 3 years of follow-up","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAccording to data published by the International Agency for Research on Cancer (IARC) in 2020, liver cancer ranks sixth among the most common malignant tumors and is the third leading cause of tumor-related death worldwide[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. The annual incidence of hepatocellular carcinoma (HCC) is increasing. The literature reports that only 5\u0026ndash;15% of HCC cases are suitable for surgical resection[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Microwave ablation (MWA), known as a thermal ablation technique, offers benefits such as rapid ablation speed, extensive coverage, minimal interference from thermal deposition, and excellent tolerability and repeatability[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. It has become a key treatment modality for HCC, especially for smaller tumor foci, where it shows superior therapeutic efficacy[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. While there is a growing body of clinical research on the application of MWA for treating HCC, managing liver tumor lesions located at the hepatic dome remains a great challenge because of factors such as blockage from the ribs and the risk of adjacent tissue (diaphragm or lung) injury. This intricate anatomy complicates the puncture process, increasing the risk of complications, which has long been a significant challenge in liver carcinoma ablation therapy[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. The caudal‒cranial direction puncture pathway (CCDPP) is a method that we propose for guiding the puncture process and is much different from the method in the cross-sectional plane normally used in clinical practice. It involves inserting a needle from a point below the plane of the costophrenic angle, pushing the needle from the caudal to cranial direction within the coronal or sagittal plane under CT guidance, and the process of puncture and ablation is finished mainly under the guidance of coronal or sagittal images.\u003c/p\u003e \u003cp\u003eThe CCDPP may avoid passing through the diaphragm and lungs and decrease the risk of the ablation procedure. In this retrospective study, data were collected and analyzed from 22 patients with HCC lesions located at the hepatic dome at our institution between March 2019 and June 2023 to assess the efficacy, safety and midterm oncological outcome of MWA via the CCDPP for these lesions.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eGeneral information\u003c/h2\u003e \u003cp\u003eThe Ethics Committee waived formal study approval for this retrospective investigation. All patients provided written consent for the use of their unidentified medical information for research purposes. Between March 2019 and November 2024, 29 patients with HCC lesions at the hepatic dome underwent MWA via the CCDPP. The inclusion criteria were as follows: 1. Pathological or clinical diagnosis of HCC; 2. A single lesion with a maximum diameter of \u0026le;\u0026thinsp;5 cm or up to three lesions with a maximum diameter of \u0026le;\u0026thinsp;3 cm; 3. Liver function Child‒Pugh class A or B; 4. Tumor lesions located above the plane of the costophrenic angle, with a distance between the edge of the lesion and the diaphragm\u0026thinsp;\u0026le;\u0026thinsp;10 mm; 5. The microwave antenna will pass through the diaphragm and lung tissues if puncture is performed within the cross-sectional plane; 6. There was no serious cardiac or pulmonary disease or coagulation disorders. Before ablation treatment, each patient underwent comprehensive laboratory testing, which included routine blood tests, liver and kidney function assessments, coagulation tests, and cardiopulmonary function evaluations. Preprocedural imaging studies included enhanced CT and/or MRI. In addition, after describing the benefits of taking TACE therapy before MWA, some patients chose to receive TACE therapy before MWA therapy.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eMWA program\u003c/h3\u003e\n\u003cp\u003eMWA was performed by two interventional radiologists, each with over five years of MWA experience. A 40-slice spiral CT machine (model U550, united imaging, China) was used for image guidance. The ablation equipment included an MTI-5A MWA system (Nanjing Great Wall Medical Equipment Co., Ltd.), featuring a microwave output frequency of (2450\u0026thinsp;\u0026plusmn;\u0026thinsp;30) MHz and an adjustable output power range of 0\u0026ndash;120 W. A water-cooled circulating MWA antenna with effective lengths of 150 mm, 180 mm, and 210 mm; a diameter of 2 mm; and a microwave emission length of 10 mm was utilized.\u003c/p\u003e \u003cp\u003eAblation was conducted under local anesthesia or sedation with dexmedetomidine (0.5 \u0026micro;g/kg), and patients\u0026rsquo; vital signs were continuously monitored. Patients were placed in the supine or prone position on the basis of the lesion's location. A CT scan with a 5-mm layer thickness and 1.0 pitch was performed when respiratory motion was absent. A coronal or sagittal MPR was immediately performed on the postprocessing interface in the CT machine, and a specific CCDPP within the coronal or sagittal plane was planned to ensure that the puncture path could avoid passing through critical anatomical structures such as the diaphragm, lung tissue, kidney and major blood vessels and that most of the pathway remained within the liver parenchyma. After the CCDPP was determined, the puncture point was marked on the body surface, disinfected, and draped. Local anesthesia (2% lidocaine) was administered to the puncture site, after which the microwave ablation needle was inserted through the designated point and pushed following the predetermined CCDPP. After the needle was pushed forward 3\u0026ndash;5 cm, another CT scan was performed, and coronal or sagittal images were reconstructed on the postprocessing interface. The angle, position, and depth of the needle were observed and adjusted according to the predetermined CCDPP before further advancing the needle. Once the placement of the ablation needle at the predetermined position within the lesion was confirmed, the microwave ablator was connected, and the ablation parameters were carefully selected according to the size and location of the lesion. The administration of microwave energy will last until the ablated region fully covers the tumor lesion and has at least a 5 mm safety margin. After the ablation procedure, an enhanced CT scan was performed to assess the effectiveness of the treatment. Evaluating whether complete ablation has been achieved is mainly based on coronal or sagittal images. Typically, the ablation region exhibited a low-density region, and if a lesion was fully covered by a low-density region with a safety margin greater than 5 mm, the lesion was considered to be completely ablated. If any residual lesion was identified, the position of the needle tip was adjusted, and the ablation process was repeated. At the end of the procedure, a 10-second needle tract ablation was carried out to prevent tumor implantation and bleeding. After removing the ablation needle, an additional CT scan was performed to confirm the absence of complications such as pneumothorax, pleural effusion, subperitoneal hepatic effusion, and diaphragmatic perforation.\u003c/p\u003e \u003cp\u003eAfter the operation, the patient was placed on bed rest, and vital signs were monitored. The patient also received routine treatments such as liver function protection, hemostasis, and infection prevention. Laboratory examinations, such as liver function tests and routine blood tests, were performed 2 to 3 days postoperation, and the patient was discharged when no abnormalities were found.\u003c/p\u003e\n\u003ch3\u003eObservation indicators\u003c/h3\u003e\n\u003cp\u003eThe success rate of the puncture technique (defined as the number of lesions where the ablation needle successfully punctures the center of the lesion divided by the total number of lesions), the success rate of ablation completion (defined as the number of lesions for which MWA treatment was completed divided by the total number of lesions), and the complication rate were evaluated. The length of the puncture path (defined as the distance from the transcutaneous entry point to the tip of the ablation needle when the tip reaches the lesion) and the number of CT scans (defined as the total number of CT scans per procedure, from the first scan until the lesion was ready for ablation) were recorded.\u003c/p\u003e\n\u003ch3\u003eFollow-up\u003c/h3\u003e\n\u003cp\u003eOne month after the ablation procedure, patients were monitored via enhanced CT or MRI. If a tumor showed hypointense features with no enhancement at any of the three scan phases in the enhanced CT/MRI scan, the efficacy of the lesion was classified as complete ablation (CA). Conversely, if any enhancement was revealed in the tumor region or its edge in the arterial or portal vein phase, the result was classified as incomplete ablation (ICA). For patients with ICA, a repeat MWA procedure may be considered. Subsequent evaluations, including enhanced CT/MRI scans, tumor markers, and other relevant factors, should be conducted every three to six months to monitor tumor progression. Local tumor progression (LTP) was identified by a dispersed, nodular, or irregularly enhanced pattern surrounding the ablation region on contrast-enhanced CT or MR images during follow-up. If LTP is identified during follow-up, the multidisciplinary team will reach a unanimous decision to proceed with further treatment, such as MWA or TACE, on the basis of the CT/MRI assessment of tumor status. The primary follow-up data included disease-free survival (DFS) and overall survival (OS) data. DFS was defined as the period from the day of the MWA procedure to the time of tumor recurrence or death from any cause, whereas OS was defined as the period from treatment initiation to the date of death or the last follow-up visit. Posttreatment lesions were described by imaging according to internationally standardized terminology. At the end of follow-up, all available cross-sectional images after MWA were reviewed to assess the effects on the abdomen. MWA adverse events reported in the book and during postoperative hospitalization were graded according to the Common Terminology Criteria for Adverse Events (CTCAE) v5.0[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eStatistical analysis was conducted via SPSS version 26 (IBM SPSS Statistics). Data are presented as either the mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation or median (range) for continuous variables or as the number and percentage for categorical variables. To compare differences between groups for continuous variables, a t test or the nonparametric Wilcoxon Mann‒Whitney test was used. For qualitative variables, a chi-square test or Fisher\u0026rsquo;s exact test was employed. Kaplan‒Meier survival curves were used to determine one-, two-, and three-year relapse-free survival rates and overall survival rates, as well as to construct survival curves. Statistical significance was defined as a p value less than 0.05.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003ePatient and tumor characteristics\u003c/h2\u003e \u003cp\u003eA total of 29 lesions from 29 patients with HCC meeting the clinical and pathological diagnosis criteria were included; the maximum diameter of the lesions was 49 mm, with a mean diameter of 25.5\u0026thinsp;\u0026plusmn;\u0026thinsp;11.0 mm; the distance between the diaphragm and the margins of the lesions was \u0026lt;\u0026thinsp;5 mm in 65.5% (19/29) of the patients and \u0026ge;\u0026thinsp;5 mm in 34.5% (10/29) of the patients. The baseline characteristics of the patients are shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\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\u003eClinical Characteristics (N\u0026thinsp;=\u0026thinsp;29)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eCharacteristic\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eValue\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eAge(years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\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\u003eMean\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e58\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\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e45ཞ76\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eGender\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\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\u003eMen\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e24\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\u003eWomen\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eEtiology of liver disease\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\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\u003eHepatitis B virus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e15\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\u003eHepatitis C virus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1\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\u003eOther\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eUnderlying liver disease\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\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\u003eLiver cirrhosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e12\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\u003eChild-Pugh class A\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e19\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\u003eChild-Pugh class B\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eTACE\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eAblation outcome ( one month later )\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\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\u003ecomplete respons\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e28\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\u003epartial response\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eTumor size (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\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\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e25.5\u0026thinsp;\u0026plusmn;\u0026thinsp;11.0\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\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.0\u0026thinsp;~\u0026thinsp;49.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eLocation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\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\u003ethe right lobe of liver\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e26\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\u003ethe left lobe of liver\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eFollow-up time(months)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\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\u003eMean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e26.03\u0026thinsp;\u0026plusmn;\u0026thinsp;17.98\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\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2\u0026thinsp;~\u0026thinsp;63\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003eHCC: hepatocellular carcinoma; TACE: transcatheter arterial chemoembolization\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eTechnical parameters and efficacy analysis of microwave ablation\u003c/h3\u003e\n\u003cp\u003eAll 29 lesions were successfully treated via the CCDPP technique, and the success rates for the puncture technique and ablation completion were 100%. The mean puncture path length during ablation was 10.88\u0026thinsp;\u0026plusmn;\u0026thinsp;1.69 cm, and the average ablation time was 9.63\u0026thinsp;\u0026plusmn;\u0026thinsp;5.17 minutes. The mean number of CT scans was 9.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.9, and the mean total number of CT scans was 24.0\u0026thinsp;\u0026plusmn;\u0026thinsp;8.6. One month after the MWA procedure, 95.5% (21/22) of all lesions were completely ablated (CA), whereas 4.5% (1/22) remained incompletely ablated (ICA). MWA was performed again on this patient, and complete ablation was achieved after the repeat treatment. (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eComplications\u003c/h2\u003e \u003cp\u003eThe pain level varies depending on the location of the lesion during the ablation procedure. The patient complained of pain in the posterior shoulder when the lesion was at the right diaphragmatic apex, whereas discomfort in the precordial region was observed when the lesion was at the left diaphragmatic apex. In this study, the incidence of intraoperative pain was 65.5% (19/29), which was relieved by adjusting the anesthetic dose. Adverse events during intraoperative and postoperative hospitalization were recorded in 21 (72.4%) of the 29 treatments, most of which were CTCAE grade 1\u0026thinsp;~\u0026thinsp;2 adverse events, including malaise, transient shortness of breath, mild pain or fever, and transient slowing of the heart rate, most of which were self-limiting or disappeared after symptomatic management. No serious complications (\u0026ge;\u0026thinsp;CTCAE grade 3), such as pneumothorax, diaphragmatic rupture, hemorrhage, pleural effusion, or biliobronchial fistula, occurred.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eSurvival analysis\u003c/h2\u003e \u003cp\u003eThe mean follow-up of all patients was 26.03\u0026thinsp;\u0026plusmn;\u0026thinsp;17.98 months. At the end of follow-up, 17.2% (5/29) of the patients experienced local tumor progression. Six patients died during the follow-up period, five after local tumor progression and one from nontumour causes. No tumor needle tract implant metastases were observed. By the end of follow-up, the 1-, 2-, and 3-year disease-free survival rates were 88.1%, 74.2%, and 74.2%, respectively, and the 1-, 2-, and 3-year overall survival rates were 91.8%, 72.4%, and 72.4%, respectively. (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eSubgroup analysis\u003c/h2\u003e \u003cp\u003eComparison between the group with lesion margins\u0026thinsp;\u0026ge;\u0026thinsp;5 mm away from the diaphragm and the group with margins\u0026thinsp;\u0026lt;\u0026thinsp;5 mm: the differences in the rates of complete local ablation; 1-, 2-, and 3-year disease-free survival; and 1-, 2-, and 3-year overall survival were not statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eMWA is a minimally invasive local treatment for early-stage HCC and metastatic liver tumors. Its efficacy has been supported by multiple studies, which indicate that its long-term prognosis is comparable to that of surgery[\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. The location of the tumor is a crucial factor influencing local recurrence after percutaneous ablation[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. HCC located in the hepatic dome is susceptible to complications, including lung injury, phrenic nerve or diaphragm injury, pneumothorax, and peritoneal burns during the process of puncture and ablation, owing to its proximity to the diaphragm and lung tissue. Therefore, ablating HCC lesions near the diaphragm poses unique challenges. Previous studies have examined various techniques for ablating tumors at the liver apex near the diaphragm, including percutaneous transdiaphragmatic and percutaneous transpulmonary approaches guided by ultrasound or CT imaging. However, these studies reported a high incidence of complications, including hemothorax, pneumothorax, lung injury, and diaphragmatic rupture, with rates reaching 28.6%[\u003cspan additionalcitationids=\"CR14\" citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Other studies concerning conventional cross-sectional puncture and ablation in combination with other methods, such as artificial pleural fluid[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] and artificial ascites[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], or ablations through open surgery or laparoscopic approaches[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] have been conducted. However, these methods increase patient suffering, healthcare costs, and the incidence of medically induced or treatment-related adverse effects, resulting in multiple complications. Although in recent years, the development of electromagnetic navigation and image fusion technology can accurately guide the ablation probe puncture into the tumor lesion and improve the puncture operation efficiency, the supporting equipment is expensive and requires additional purchase, which limits the popularity and accessibility of these technologies.\u003c/p\u003e \u003cp\u003ePrevious studies have described various CT-guided puncture methods for lesions at the top of the hepatic diaphragm, including \"craniocaudal tilt\"[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], \"angled puncture,\" \"angled approach\"[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], and \"nonpleural approach\"[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. However, few studies have explained the specific procedures of these methods in detail. On the basis of our experience in a single-center setting and a review of the literature, we proposed the CCDPP method and applied it in the clinic. The CCDPP technique involves determining the pathway of the ablation needle in a direction from the caudal to the cranial and determining the extent of the ablation region within the coronal or sagittal plane during the procedure. With the excellent spatial and tissue resolution of the reconstructed coronal or sagittal image, the depth and angle of the ablation needle's entry, the location of the lesion, and the distance between the needle tip and the lesion can be easily visualized, helping the operator exactly adjust the path of the puncture to achieve a successful puncture. The large inclined angle of needle puncture used in the CCDPP reduces the possibility of bleeding by compressing the needle path with the help of the gravity of the upper liver tissue. As the needle is parallel or almost parallel to the diaphragm, this method also has the following advantages: first, it ensures that the needle can pass through normal liver tissue to reach the lesion rather than through the lung or diaphragm, reducing the occurrence of complications such as puncture-related injury of the diaphragm and lung tissue or needle tract bleeding; second, as most lesions are found to grow parallel to the diaphragm, it also ensures that the ablation region and the shape of the tumor match each other very well to achieve appropriate coverage of the ablation region.\u003c/p\u003e \u003cp\u003eIn addition, the significant improvements in the scanning speed and computing speed of multislice spiral CT have significantly reduced the time delay of the MPR (multiplanar reconstruction) needed for coronal or sagittal images. This makes it technically possible to finish the puncture operation within the coronal or sagittal plane by applying the CCDPP in the ablation of hepatic dome tumors without delay. The majority of hospitals can carry out ablation treatment in this way by using existing CT equipment without increasing the cost of acquiring additional equipment. Nazanin et al. reported an overall success rate of 94% for CT-guided MWA of 48 hepatic fornix tumors, with an average tumor size of 2.2 cm, including patients who underwent successful repeat treatments[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. In our study, of the 29 patients treated with ablation via the CCDPP, the success rate for both the puncture technique and ablation completion was 100%, suggesting that the CCDPP is technically applicable in clinical practice.\u003c/p\u003e \u003cp\u003eIn our study, one-month postoperative follow-up imaging revealed primary complete ablation (CA) in 96.6% (28/29) of the lesions, while the average diameter of the lesions was 25.5 mm, which was greater than those reported in previous studies. Favorable clinical and oncological outcomes in the middle term were also achieved even when the lesion edge was less than 5 mm away from the diaphragm. Teng et al. reported that ablation safety margins less than 5 mm were associated with a higher local tumor progression rate following thermal ablation of HCC, with a 46% risk reduction for each 5 mm increase in the minimum margin size[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. It is generally believed that to achieve complete ablation, the ablation boundary typically needs to extend beyond the tumor margin by at least 5 to 10 mm[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. However, why is the CA rate comparable to previous findings in this study, even for most lesions\u0026thinsp;\u0026lt;\u0026thinsp;5 mm away from the diaphragm? The authors believe that the reason is as follows: the needle body of the microwave antenna is parallel to the diaphragm, and the possibility of the microwave antenna working area penetrating the diaphragm for ablation is avoided. If this is the case, catastrophic and severe complications, such as biliary pleural fistula, bronchobiliary fistula or major bleeding, inevitably occur. Typically, in my study, the long axis of the ablation zone was found to be parallel to that of the tumor as well as the diaphragm on coronal or sagittal images. Although the ablation zone touches the diaphragm in a wide basement way, the diaphragm remains undamaged, and exudation in adjacent lungs is also not identified. This makes the operator more conficient when the ablation machine is working and when the ablation is as thorough as possible.\u003c/p\u003e \u003cp\u003ePrevious studies have reported that local tumor progression (LTP) rates are 5\u0026ndash;15.1% for MWA treatment of HCC lesions less than 3 cm in diameter2728(27,28). Several studies have shown that tumor size and inadequate ablation margins are significant factors influencing local tumor progression[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. In this study, LTP was observed in 17.2% (5/29) of the lesions during the follow-up period. The higher rate of LTP in this study than in previous reports may be related to the larger average diameter of the lesions, the small number of patients enrolled, and the longer duration of follow-up.\u003c/p\u003e \u003cp\u003eVarious studies have confirmed the therapeutic efficacy of TACE-MWA[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. TACE administered before ablation can diminish or obstruct the local blood supply to the tumor, leading to more thorough ablation and a reduced likelihood of local recurrence. This approach also diminishes the heat sink effect and the potential for hematogenous metastasis and implantation metastasis of the tumor during the MWA procedure[\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. DSA examination has the ability to detect and embolize tiny lesions that may not be discernible through imaging modalities such as ultrasound, CT, and MRI. Additionally, iodine‒oil deposition, which is high density in CT images, serves as a tracer and increases the visibility of tumors on plain CT scans. In our study, 62.1% (18/29) of the patients underwent TACE prior to MWA, accounting for the high complete ablation rate achieved during follow-up.\u003c/p\u003e \u003cp\u003eThe occurrence of abdominal pain and discomfort following thermal ablation is reported to be 80.1% when the liver cancer lesion is situated below the diaphragm or in close proximity to the hepatic pericardium[\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. The predominant intraoperative and postoperative complication observed in this patient cohort was pain, predominantly presenting as right upper abdominal discomfort or shoulder pain exacerbated by respiratory movements. Two patients experienced heart rate slowing during the procedure, which improved with intravenous medication, and successfully completed the ablation. Nausea, vomiting, and hypothermia are all common complications after ablation, which may be the response of an organism to visceral nerve reflexes and the stimulation of inflammatory mediators released from necrotic tissues[\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. All the apparent complications could be relieved after symptomatic treatment without serious complications such as bleeding, hemothorax, pneumothorax, diaphragm injury, and cholangio-pleural fistula, which indicated that CT-guided MWA via the CCDPP was safe and feasible for the treatment of HCC in the hepatic dome.\u003c/p\u003e \u003cp\u003eIn conclusion, CT-guided microwave ablation combined with the CCDPP method for the treatment of small HCC at the top of the liver dome did not increase the difficulty of puncture or decrease the technical success rate. Complete ablation could still be achieved even for lesions less than 5 mm away from the diaphragm, indicating that the method is feasible and provides an alternative to solve the problem of puncture access for ablation of liver tumors very close to the diaphragm. However, this study is a single-center retrospective study with a small number of cases, which has limitations, and a multicenter study with a larger sample size and longer follow-up is still warranted to confirm the safety and effectiveness of this method.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eT conceived the article; T and X collected the data; T and X, assembled the data; T and L provided the study materials, wrote the manuscript and approved the manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eThe authors thank the colleagues in the imaging department for the medical images provided. The author would also like to thank the patient for agreeing to disclose the details of the case for publication.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eSung H, Ferlay J, Siegel RL, et al. 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Efficacy and safety of percutaneous microwave ablation for hepatocellular carcinomas \u0026lt;4 cm in difficult location. \u003cem\u003eBJR\u003c/em\u003e. 2020;93(1116):20191025.\u003c/li\u003e\n\u003cli\u003eToyoda M. Computed tomography-guided transpulmonary radiofrequency ablation for hepatocellular carcinoma located in hepatic dome. \u003cem\u003eWJG\u003c/em\u003e. 2006;12(4):608.\u003c/li\u003e\n\u003cli\u003eMiura H, Yamagami T, Terayama K, Yoshimatsu R, Matsumoto T, Nishimura T. Pneumothorax induced by radiofrequency ablation for hepatocellular carcinoma beneath the diaphragm under real-time computed tomography-fluoroscopic guidance. \u003cem\u003eActa Radiol\u003c/em\u003e. 2010;51(6):613-618.\u003c/li\u003e\n\u003cli\u003eKim YK, Kim CS, Lee JM, Chung GH, Chon SB. 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Computed tomography-guided percutaneous microwave ablation with artificial ascites for problematic hepatocellular tumors. \u003cem\u003eInternational Journal of Hyperthermia\u003c/em\u003e. 2020;37(1):256-262.\u003c/li\u003e\n\u003cli\u003eHead HW, Dodd GD, Dalrymple NC, et al. Percutaneous Radiofrequency Ablation of Hepatic Tumors against the Diaphragm: Frequency of Diaphragmatic Injury \u003csup\u003e1\u003c/sup\u003e. \u003cem\u003eRadiology\u003c/em\u003e. 2007;243(3):877-884.\u003c/li\u003e\n\u003cli\u003eKurokohchi K, Hirai S, Ohgi T, et al. Thoracoscopic ethanol injection and radiofrequency ablation for the treatment of hepatocellular carcinoma located immediately under the diaphragm. \u003cem\u003eInt J Oncol\u003c/em\u003e. 2006;29(2):375-380.\u003c/li\u003e\n\u003cli\u003eChen J, Lin Z, Lin Q, Lin R, Yan Y, Chen J. Percutaneous radiofrequency ablation for small hepatocellular carcinoma in hepatic dome under MR-guidance: clinical safety and efficacy. \u003cem\u003eInternational Journal of Hyperthermia\u003c/em\u003e. 2020;37(1):192-201.\u003c/li\u003e\n\u003cli\u003eSchullian P, Putzer D, Laimer G, Levy E, Bale R. Feasibility, safety, and long-term efficacy of stereotactic radiofrequency ablation for tumors adjacent to the diaphragm in the hepatic dome: a case-control study. \u003cem\u003eEur Radiol\u003c/em\u003e. 2020;30(2):950-960.\u003c/li\u003e\n\u003cli\u003eFilippiadis DK, Spiliopoulos S, Konstantos C, et al. Computed tomography-guided percutaneous microwave ablation of hepatocellular carcinoma in challenging locations: safety and efficacy of high-power microwave platforms. \u003cem\u003eInternational Journal of Hyperthermia\u003c/em\u003e. 2018;34(6):863-869.\u003c/li\u003e\n\u003cli\u003eAsvadi NH, Anvari A, Uppot RN, Thabet A, Zhu AX, Arellano RS. CT-Guided Percutaneous Microwave Ablation of Tumors in the Hepatic Dome: Assessment of Efficacy and Safety. \u003cem\u003eJournal of Vascular and Interventional Radiology\u003c/em\u003e. 2016;27(4):496-502.\u003c/li\u003e\n\u003cli\u003eTeng W, Liu KW, Lin CC, et al. Insufficient Ablative Margin Determined by Early Computed Tomography May Predict the Recurrence of Hepatocellular Carcinoma after Radiofrequency Ablation. \u003cem\u003eLiver Cancer\u003c/em\u003e. 2015;4(1):26-38.\u003c/li\u003e\n\u003cli\u003eHasegawa K, Kokudo N, Makuuchi M, et al. Comparison of resection and ablation for hepatocellular carcinoma: A cohort study based on a Japanese nationwide survey. \u003cem\u003eJournal of Hepatology\u003c/em\u003e. 2013;58(4):724-729.\u003c/li\u003e\n\u003cli\u003eVogl T, Nour-Eldin NE, Hammerstingl R, Panahi B, Naguib N. Microwave Ablation (MWA): Basics, Technique and Results in Primary and Metastatic Liver Neoplasms \u0026ndash; Review Article. \u003cem\u003eFortschr R\u0026ouml;ntgenstr\u003c/em\u003e. 2017;189(11):1055-1066.\u003c/li\u003e\n\u003cli\u003eMeloni M, Galimberti S, Dietrich C, et al. Microwave ablation of hepatic tumors with a third generation system: loco‑regional efficacy in a prospective cohort study with intermediate term follow-up. \u003cem\u003eZ Gastroenterol\u003c/em\u003e. 2016;54(06):541-547.\u003c/li\u003e\n\u003cli\u003eKim Y sun, Rhim H, Cho OK, Koh BH, Kim Y. Intrahepatic recurrence after percutaneous radiofrequency ablation of hepatocellular carcinoma: Analysis of the pattern and risk factors. \u003cem\u003eEuropean Journal of Radiology\u003c/em\u003e. 2006;59(3):432-441.\u003c/li\u003e\n\u003cli\u003eZheng L, Li HL, Guo CY, Luo SX. Comparison of the Efficacy and Prognostic Factors of Transarterial Chemoembolization Plus Microwave Ablation versus Transarterial Chemoembolization Alone in Patients with a Large Solitary or Multinodular Hepatocellular Carcinomas. \u003cem\u003eKorean J Radiol\u003c/em\u003e. 2018;19(2):237.\u003c/li\u003e\n\u003cli\u003eSmolock AR, Cristescu MM, Hinshaw A, et al. Combination transarterial chemoembolization and microwave ablation improves local tumor control for 3- to 5-cm hepatocellular carcinoma when compared with transarterial chemoembolization alone. \u003cem\u003eAbdom Radiol\u003c/em\u003e. 2018;43(9):2497-2504.\u003c/li\u003e\n\u003cli\u003eZhang YJ, Chen MS, Chen Y, Lau WY, Peng Z. Long-term Outcomes of Transcatheter Arterial Chemoembolization Combined With Radiofrequency Ablation as an Initial Treatment for Early-Stage Hepatocellular Carcinoma. \u003cem\u003eJAMA Netw Open\u003c/em\u003e. 2021;4(9):e2126992.\u003c/li\u003e\n\u003cli\u003eLiu C, He J, Li T, Hong D, Su H, Shao H. Evaluation of the efficacy and postoperative outcomes of hydrodissection-assisted microwave ablation for subcapsular hepatocellular carcinoma and colorectal liver metastases. \u003cem\u003eAbdom Radiol\u003c/em\u003e. 2021;46(5):2161-2172.\u003c/li\u003e\n\u003cli\u003eLiang P, Wang Y, Yu X, Dong B. Malignant Liver Tumors: Treatment with Percutaneous Microwave Ablation\u0026mdash;Complications among Cohort of 1136 Patients. \u003cem\u003eRadiology\u003c/em\u003e. 2009;251(3):933-940.\u003c/li\u003e\n\u003cli\u003eZhou F, Yu X ling, Liang P, et al. Microwave ablation is effective against liver metastases from gastric adenocarcinoma. \u003cem\u003eInternational Journal of Hyperthermia\u003c/em\u003e. Published online March 29, 2017:1-6.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bsur","sideBox":"Learn more about [BMC Surgery](http://bmcsurg.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bsur/default.aspx","title":"BMC Surgery","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Microwave Ablation, Hepatocellular Carcinoma, Hepatic Dome, Caudal-Cranial direction puncture pathway, CT Coronal (Sagittal) Reconstruction","lastPublishedDoi":"10.21203/rs.3.rs-6213729/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6213729/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo evaluate the clinical efficacy of microwave ablation (MWA) for small hepatocellular carcinoma (HCC) located at the hepatic dome via the caudal‒cranial direction puncture (CCDPP) within the coronal or sagittal plane under computed tomography (CT) guidance.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA retrospective analysis was conducted to analyze data from 29 patients with HCC located at the hepatic dome who underwent CT-guided MWA from March 2019 to November 2024. The puncture path of the microwave antenna during ablation is from caudal to cephalic within the coronal or sagittal planes reconstructed via multislicespiral CT. Baseline patient data were collected, and outcomes, including the puncture technique success rate, ablation success rate, and incidence of complications, were observed. Kaplan‒Meier survival curve analysis was used to calculate the disease-free survival (DFS) and overall survival (OS) rates of all patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe puncture technique and ablation success rates were both 100%, and no serious complications occurred. One month post-MWA, enhanced abdominal CT or MRI scans revealed complete ablation in 96.6% of all patients, whereas 3.4% (1/29) had incomplete ablation, necessitating additional MWA treatment. By the cutoff of follow-up, the mean follow-up time for all patients was 26.03 ± 17.98 months. The local tumor progression rate was 22.7%, and the 1-, 2-, and 3-year disease-free survival rates were 88.1%, 74.2%, and 74.2%, respectively. The 1-, 2-, and 3-year overall survival rates were 91.8%, 72.4%, and 72.4%, respectively.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMicrowave ablation with the CCDPP used in the puncture process is safe, feasible, and effective, with acceptable oncological midterm outcomes for the treatment of small HCC lesions in the hepatic dome.\u003c/p\u003e","manuscriptTitle":"Clinical efficacy of MWA via the caudal‒cranial puncture pathway for small hepatocellular carcinoma at the hepatic dome: 3 years of follow-up","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-26 09:21:36","doi":"10.21203/rs.3.rs-6213729/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-04-01T05:23:21+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-03-27T09:27:54+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-03-27T09:25:26+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Surgery","date":"2025-03-12T16:09:33+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bsur","sideBox":"Learn more about [BMC Surgery](http://bmcsurg.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bsur/default.aspx","title":"BMC Surgery","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7721309b-4e7d-4a52-bb7d-fa11072f9057","owner":[],"postedDate":"March 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-01-12T16:05:39+00:00","versionOfRecord":{"articleIdentity":"rs-6213729","link":"https://doi.org/10.1186/s12893-025-03290-0","journal":{"identity":"bmc-surgery","isVorOnly":false,"title":"BMC Surgery"},"publishedOn":"2026-01-08 15:58:50","publishedOnDateReadable":"January 8th, 2026"},"versionCreatedAt":"2025-03-26 09:21:36","video":"","vorDoi":"10.1186/s12893-025-03290-0","vorDoiUrl":"https://doi.org/10.1186/s12893-025-03290-0","workflowStages":[]},"version":"v1","identity":"rs-6213729","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6213729","identity":"rs-6213729","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}