Perioperative Efficacy and Survival Prognosis of Subxiphoid Versus Intercostal Thoracoscopic Surgery for Large-Sized Thymoma: A Multicenter Retrospective Study

Perioperative Efficacy and Survival Prognosis of Subxiphoid Versus Intercostal Thoracoscopic Surgery for Large-Sized Thymoma: A Multicenter Retrospective Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Perioperative Efficacy and Survival Prognosis of Subxiphoid Versus Intercostal Thoracoscopic Surgery for Large-Sized Thymoma: A Multicenter Retrospective Study Lichen Zhang, Zhengwei Huang, Jiajing Sun, Yingyu Zhu, Sheng Lu, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8464955/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 5 You are reading this latest preprint version Abstract Background Anterior mediastinal tumors, including thymoma, teratoma, lipoma, and pericardial cyst, represent the most common subtype of mediastinal tumors, among which thymoma is the most prevalent malignant tumor in the anterior mediastinum. With the widespread application of high-resolution spiral computed tomography (HRCT) and the intensification of health screening, the detection rate of thymoma has been significantly improved. Surgical resection remains the cornerstone of treatment, with intercostal video-assisted thoracoscopic surgery (IVATS) serving as the mainstream approach. In recent years, under the principles of enhanced recovery after surgery (ERAS), the subxiphoid VATS (SVATS) approach has attracted considerable attention. Nevertheless, robust evidence-based data comparing its perioperative efficacy and postoperative survival outcomes with the traditional intercostal approach for anterior mediastinal tumor resection remains lacking. Methods This retrospective study included 138 patients with thymomas (5.0–10.0 cm) who underwent subxiphoid or intercostal VATS at two hospitals from January 2018 to January 2023. Clinical data, intraoperative and postoperative outcomes, complications and overall survival were analyzed. The primary endpoints included overall survival (OS), intraoperative blood loss, and duration of postoperative oral analgesic use. The secondary endpoints comprised postoperative drainage volume, operative time, postoperative length of hospital stay, and postoperative complications. Results After matching, 138 patients were analyzed, drainage volume (subxiphoid: 437.09 ± 410.75 mL, intercostal: 662.71 ± 690.83 mL, P = 0.017), and duration of postoperative analgesic use (subxiphoid: 2.11 ± 1.27 days, intercostal: 3.88 ± 1.04 days, P < 0.001). Overall survival were prestened (HR for death, 0.3 95% CI, 0.06 to 2.20; P = 0.25). Conclusion Compared with IVATS, SVATS for large thymomas is associated with less postoperative drainage volume and shorter duration of oral analgesic use, demonstrating advantages in short-term perioperative efficacy. thymomas SVATS IVATS Multicenter Study Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Anterior mediastinal tumors, including thymoma, teratoma, lipoma, and pericardial cyst, represent the most common type of mediastinal tumors. With the popularization of routine health screening and the widespread application of high-resolution spiral computed tomography (HRCT), the detection rate of these tumors has been significantly improved. Among anterior mediastinal tumors, thymoma is the most prevalent, and surgical resection remains the mainstay of treatment for this condition. Compared with traditional open thoracotomy, video-assisted thoracoscopic surgery (VATS) has gained widespread preference due to its minimally invasive nature, cosmetic benefits, reduced postoperative complications, alleviated pain, and accelerated recovery ( 1 ).Currently, the intercostal VATS (IVATS) approach serves as the mainstream technique ( 2 , 3 ). In recent years, with the growing emphasis on enhanced recovery after surgery (ERAS), the subxiphoid VATS (SVATS) approach has emerged as an alternative. By placing the incision under the xiphoid process, SVATS can avoid intercostal nerve injury, thereby mitigating postoperative pain. Furthermore, this approach provides a superior surgical field of view, enabling clear visualization of the anatomical relationships between the tumor and critical structures such as the innominate vein and superior vena cava, thus attracting considerable attention among thoracic surgeons ( 4 ).Nevertheless, robust evidence comparing the perioperative outcomes and long-term postoperative survival of patients undergoing SVATS versus IVATS for thymoma resection remains scarce. Therefore, this study aims to compare the clinical efficacy and postoperative survival outcomes between SVATS and IVATS in the treatment of anterior mediastinal tumors, explore the potential advantages of SVATS, and provide valuable insights for clinical decision-making. Methods This retrospective study enrolled patients with large thymomas who underwent subxiphoid or intercostal video-assisted thoracoscopic surgery (VATS) at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, and The First Affiliated Hospital, Zhejiang University School of Medicine, between January 2018 and January 2023. A total of 138 patients were included, with 72 cases from Sir Run Run Shaw Hospital and 66 cases from The First Affiliated Hospital. Among them, 49 patients underwent subxiphoid VATS (16 cases from Sir Run Run Shaw Hospital and 33 cases from The First Affiliated Hospital), and 89 patients received intercostal VATS (56 cases from Sir Run Run Shaw Hospital and 33 cases from The First Affiliated Hospital), as shown in Fig. 1 . This study was approved by the Clinical Research Ethics Committee of The First Affiliated Hospital, Zhejiang University School of Medicine (2022 IIT No. 1166) and Sir Run Run Shaw Hospital, Zhejiang University School of Medicine (2025 No. 1067). The study was conducted in compliance with the Declaration of Helsinki (revised 2013) and Good Clinical Practice (GCP) guidelines. All patients provided written informed consent for the use of their medical record data. All patients underwent contrast-enhanced computed tomography (CECT) to assess the size, location, and invasiveness of the lesions. Large thymomas were defined as tumors with a maximum diameter of ≥ 5.0 cm and ≤ 10.0 cm on CECT scans (Figs. 2 and 3 ). Inclusion criteria: Age between 18 and 80 years. Thymoma with or without invasion of the pericardium, lung, or left innominate vein. Tumor diameter ≥ 5.0 cm and ≤ 10.0 cm. American Society of Anesthesiologists (ASA) physical status I–II.Adequate organ function and cardiopulmonary reserve. Exclusion criteria:Absence of pretreatment imaging.Myasthenia gravis.Bleeding disorders.Clinically significant concurrent malignancies.Invasion of surrounding organs (except pericardium, lung, and left innominate vein). Distant metastasis.Surgical indications:Adequate organ function and cardiopulmonary reserve to tolerate surgery. Absence of bleeding disorders.No invasion of surrounding organs (except pericardium, lung, and left innominate vein).No distant metastasis. The choice of surgical approach (subxiphoid VATS or intercostal VATS) was determined by the surgeon following thorough discussion. Data were collected through regular patient follow-ups or hospital visits, including baseline characteristics (age, body mass index BMI, sex, smoking status, alcohol consumption, comorbidities hypertension, diabetes, coronary heart disease, ASA status, tumor diameter,Masaoka-Koga and Pathology), intraoperative and postoperative outcomes (operation time, blood loss, intensive care unit ICU stay, drainage duration, drainage volume, postoperative hospital stay, duration of postoperative oral analgesics nonsteroidal anti-inflammatory drugs (NSAIDs), twice daily, R0 resection, and conversion to open surgery), and postoperative complications (pleural effusion, pneumothorax, pulmonary infection, chylothorax, subcutaneous emphysema, arrhythmia, postoperative hemorrhage, phrenic nerve paralysis, and reoperation). Follow-up was conducted for at least 36 months postoperatively. The primary endpoints included overall survival (OS), intraoperative blood loss, and duration of postoperative oral analgesic use. The secondary endpoints comprised postoperative drainage volume, operative time, postoperative length of hospital stay, and postoperative complications. Subxiphoid VATS Procedure: Under general anesthesia with double-lumen endotracheal intubation, patients were placed in a supine position with legs apart for unilateral lung ventilation. The surgeon stood between the patient’s legs, and the assistant stood on the patient’s right side. A longitudinal incision was made at the lower edge of the xiphoid process as the observation port for a 10-mm, 30-degree rigid thoracoscope. The rectus abdominis muscle was dissected vertically, and the retrosternal space was bluntly dissected with the surgeon’s finger to expand the working space. Two operative ports were created at the midclavicular line crossing the bilateral costal arches for the insertion of an ultrasonic scalpel and thoracoscopic graspers. An artificial pneumomediastinum was established using carbon dioxide (CO2) insufflation, maintaining a pressure of 8 cm H2O to expand the retrosternal space and facilitate the procedure. The bilateral mediastinal pleura were opened to fully expose the intrathoracic vessels and phrenic nerves. Intercostal VATS Procedure: Under general anesthesia with double-lumen endotracheal intubation, patients were placed in a semi-lateral decubitus position at 30–45 degrees with the cranial and caudal sides tilted downward. This approach was performed through three ports: one observation port and two operative ports. The port selection depended on the tumor’s location, size, and the surgeon’s preference. During the procedure, the tumor and surrounding fatty tissue, as well as any involved organs, were resected. If the intercostal approach was not feasible, conversion to a transsternal approach or median sternotomy was performed. All specimens were retrieved in a specimen bag. A drainage tube was inserted into the thoracic cavity and removed when no air leakage was observed and the drainage volume was < 200 mL within 24 hours.performed through three ports: one observation port and two operative ports. The port selection depended on the tumor’s location, size, and the surgeon’s preference. During the procedure, the tumor and surrounding fatty tissue, as well as any involved organs, were resected. If the intercostal approach was not feasible, conversion to a transsternal approach or median sternotomy was performed. All specimens were retrieved in a specimen bag. A drainage tube was inserted into the thoracic cavity and removed when no air leakage was observed and the drainage volume was < 200 mL within 24 hours. Statistical Analysis Data analysis was performed using R software (version 4.2.3) and the ggplot2 package (version 3.3.5) for visualization. Statistical descriptions and inferences were conducted based on the distribution characteristics of the data. For quantitative data, the number of cases (including missing cases), minimum, maximum, mean, standard deviation, and median were reported. For qualitative data, the frequency and percentage of each variable level were presented. For time-to-event data, continuous variables were tested for normality using the Shapiro-Wilk test. Normally distributed data were expressed as mean ± standard deviation, while non-normally distributed data were expressed as median ± interquartile range (IQR). Based on normality, either the t-test or Wilcoxon rank-sum test was applied. Categorical data were expressed as frequencies and analyzed using Pearson’s chi-square test or Fisher’s exact test. A p-value < 0.05 was considered statistically significant. Table 1 Characteristics of the patients at baseline Variables Subxiphoid approach(n = 49) Intercostal approach(n = 89) P-value Age (years, mean ± SD) 53.54 ± 13.46 52.74 ± 15.16 0.750 BMI (kg/m2, mean ± SD) 24.55 ± 2.93 23.69 ± 3.62 0.418 Sex, n (%) 0.229 Male 30 (61.2) 45 (50.6) Female 19 (38.8) 44 (49.4) Smoking status, n (%) 0.474 Never 39 (79.6) 66 (74.2) Ever 10(20.4) 23(25.8) Drinking status, n (%) 0.301 Never 43 (87.7) 72 (80.9) Ever 6 (22.3) 17 (19.1) ASA status class, n (%) 0.163 I 18 (36.7) 30 (33.7) II 31 (63.3) 59 (66.3) Comorbidity, n (%) 17 (34.7) 21 (23.6) 0.721 Tumor diameter (cm), mean ± SD (range) 6.3 ± 1.4(5.0–10.0) 6.24 ± 1.3(5.0–10.0) 0.547 Masaoka-Koga Ⅰ 15(30.6) 12(13.4) 0.102 ⅡA 10(20.4) 31(34.8) ⅡB 14(28.6) 27(30.3) ⅢA 7(14.3) 16(18.1) ⅢB 3(6.1) 3(3.4) Pathology Thymic carcinoma, n (%) 11 (22.4) 13 (14.6) 0.492 Type A thymic tumor, n (%) 5 (10.2) 9 (10.1) Type B1 thymic tumor, n (%) 5 (10.2) 10 (11.1) Type B2 thymic tumor, n (%) 7 (14.3) 22 (24.7) Type B3 thymic tumor, n (%) 5 (10.2) 4 (4.5) Type AB thymic tumor, n (%) 16 (32.7) 31 (35) Abbreviations: BMI, Body Mass Index; ASA, American Society of Anesthesiologists; SD, Standard Deviation. Comorbidities included hypertension, diabetes, and coronary heart disease. Table 2 Intraoperative and postoperative outcomes of all patients Variables Subxiphoid approach （ n=49 ） Intercostal approach （ n=89 ） P-value Operation time (min, x ± s) 120.96 ± 30.47 106.99 ± 45.74 0.058 Blood loss (ml, x ± s) 35.51 ± 48.12 31.96 ± 42.21 0.653 Drainage dura- tion (days, x ± s) 3.69 ± 2.41 3.35 ± 1.99 0.368 Volume of drain- age (ml, x ± s) 437.09 ± 410.75 662.71 ± 690.83 0.017 Postoperative hospital stay (days, x ± s) 5.14 ± 2.62 4.61 ± 1.86 0.157 Duration ofpostoperative oral analgesics (days, x ± s) 2.11 ± 1.27 3.88 ± 1.04 < 0.001 ICU stay, n (%) 4 (8.1%) 3 (3.3%) 0.220 R0 resection, n (%) 49(100.0) 89(100.0) NA Conversion to open surgery, n (%) 0(0.0) 0(0.0) NA Table 3 Postoperative complications of all patients Variables Subxiphoid approach （ n=49 ） Intercostal approach （ n=89 ） P-value Pleural effusion, n (%) 5 (10.2) 5 (5.6) 0.322 Pneumothorax, n (%) 0 (0) 0 (0) NA Pulmonary infection, n (%) 2 (4.1) 0 (0) 0.551 Chylothorax, n (%) 2 (4.1) 0 (0) 0.551 Subcutaneous emphysema, n (%) 1 (2.1) 4 (4.5) 0.463 Arrhythmias, n (%) 1 (2.1) 0 (0) 0.176 Phrenic nerve palsy, n (%) 0 (0) 2 (2.2) 0.290 Postoperative bleeding, n (%) 5 (10.2) 7 (7.9) 0.443 Results Baseline Characteristics From January 2018 to January 2023, a total of 247 patients were included in this study: 85 underwent subxiphoid VATS, and 162 underwent intercostal VATS. The baseline clinical characteristics of the two groups are shown in Table 1. There were no significant differences in age, BMI, sex, smoking status, alcohol consumption, comorbidities, ASA status, tumor diameter, or pathology and Masaoka-Koga between the two groups. (P > 0.05). Intraoperative and Postoperative Outcomes As shown in Table 2, significant differences were observed in operative time (subxiphoid: 120.96 ± 30.47 minutes, intercostal: 106.99 ± 45.74 minutes, P = 0.058), drainage volume (subxiphoid: 437.09 ± 410.75 mL, intercostal: 662.71 ± 690.83 mL, P = 0.017), and duration of postoperative analgesic use (subxiphoid: 2.11 ± 1.27 days, intercostal: 3.88 ± 1.04 days, P < 0.001). No significant differences were found in blood loss (subxiphoid: 35.51 ± 48.12 mL, intercostal: 31.96 ± 42.21 mL, P = 0.653), drainage duration (subxiphoid: 3.69 ± 2.41 days, intercostal: 3.35 ± 1.99 days, P = 0.368), postoperative hospital stay (subxiphoid: 5.14 ± 2.62 days, intercostal: 4.61 ± 1.86 days, P = 0.127), or ICU admission (subxiphoid: 4 [8.1%], intercostal: 3 [3.3%], P = 0.220). The R0 resection rate was 100% for both approaches, and no patients required conversion to open surgery. As shown in Table 3, the overall complication rates were similar between the two groups. There were no significant differences in postoperative complications, including pleural effusion, pneumothorax, pulmonary infection, chylothorax, subcutaneous emphysema, arrhythmia, or phrenic nerve paralysis (P > 0.05). Overall survival (OS) outcomes Overall survival (OS) outcomes between the subxiphoid (SVATS) and intercostal (IVATS) groups are presented in Figure 4.(HR for death, 0.3 95% CI, 0.06 to 2.20; P=0.25) Conclusion Compared with traditional open thoracotomy, intercostal video-assisted thoracoscopic surgery (IVATS) features smaller lateral incisions, rendering the wounds cosmetically less conspicuous (5). Multiple studies have demonstrated that IVATS offers advantages such as reduced intraoperative blood loss, shorter chest tube indwelling time, shorter hospital stay, fewer postoperative complications, and comparable oncological outcomes(6, 7). Nevertheless, it has certain limitations, including difficulty in exposing the contralateral phrenic nerve, and intercostal nerve injury that may lead to chronic incision pain and numbness(8). The subxiphoid VATS (SVATS) approach was developed to avoid intercostal nerve injury and alleviate postoperative pain. Several studies have indicated that compared with the intercostal approach, SVATS results in milder postoperative pain and satisfactory cosmetic outcomes(9, 10). In our previous study, we compared the perioperative indicators among IVATS, SVATS, and open thoracotomy. For large anterior mediastinal masses without organ invasion, VATS was associated with less intraoperative blood loss and shorter duration of postoperative oral analgesic use than open thoracotomy(11). However, these studies focused on anterior mediastinal masses in general, encompassing benign lesions such as thymic cysts and hyperplasia as well as malignant tumors like thymoma, making the findings overly general. The present study specifically focused on malignant thymomas, comparing the perioperative efficacy and postoperative survival outcomes between SVATS and IVATS in the treatment of large thymomas. We found that compared with the intercostal approach, the subxiphoid approach was associated with less postoperative drainage volume, significantly shorter duration of postoperative oral analgesic use, and superior short-term perioperative efficacy, while there was no significant difference in 3-year survival outcomes between the two groups. Nevertheless, the operative time was longer in the SVATS group, which may be attributed to the limited experience of the surgical team and the inherent learning curve(10, 12, 13). SVATS can avoid intercostal nerve injury intraoperatively, thereby reducing postoperative pain. In addition, this approach provides a superior surgical field of view, enabling clear visualization of the anatomical relationships between the tumor and critical structures such as the innominate vein and superior vena cava(14, 15). This facilitates minimized tissue damage and potential intraoperative hemorrhage, contributing to less postoperative pain and reduced drainage volume in the short-term perioperative period.Thymomas are classified into pathological types A, AB, B1, B2, B3, and C (thymic carcinoma) (16, 17). Even type A and AB thymomas exhibit potential malignancy, so patient survival remains an important indicator for evaluating the two surgical approaches. Studies comparing IVATS and SVATS for anterior mediastinal tumors larger than 5 cm are scarce, particularly for large malignant thymomas(18-20).Therefore, we collected data from eligible patients treated at two large general hospitals between January 2018 and January 2023. The results showed no significant difference in survival outcomes between patients who underwent the two surgical procedures. In conclusion, compared with IVATS, SVATS for large thymomas is associated with less postoperative drainage volume and shorter duration of oral analgesic use, demonstrating advantages in short-term perioperative efficacy. Declarations Ethical Statement : The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. the Declaration of Helsinki (as revised in 2013). This study was approved by the Clinical Research Ethics Committee of the First Affiliated Hospital, Zhejiang University School of Medicine (2022 IIT No. 1166), Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University(2025 No. 1067) this retrospective analysis was waived Author Contribution: L.Z. (conceptualization, data curation, formal analysis, investigation, visualization, methodology, writing—original draft). Z.H. (conceptualization, data curation, formal analysis, investigation, visualization, methodology, writing—review and editing). J.S. (conceptualization, investigation, visualization, methodology, writing—original draft). S.L. andY.Z.(conceptualization, data curation, investigation, visualization, methodology). A.G. and J.L. (conceptualization, investigation, visualization, methodology). X.L. Z.C.andY.L.(conceptualization, investigation, resources, supervision, validation). Z.H. (conceptualization, funding acquisition, investigation, resources, supervision, validation). All authors contributed to the article and approved the submitted version. Funding This research was not founded. Competing interests The authors declare no competing interests. Additional information All data generated or analysed during this study are included in this published article [and its supplementary information files. References Kamel MK, Villena-Vargas J, Rahouma M, Lee B, Harrison S, Stiles BM, et al. 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Interact Cardiovasc Thorac Surg. 2017;25(1):103–8. Lu Q, Zhao J, Wang J, Chen Z, Han Y, Huang L, et al. Subxiphoid and subcostal arch Three ports thoracoscopic extended thymectomy for myasthenia gravis. J Thorac Dis. 2018;10(3):1711–20. Qiu Z, Chen L, Lin Q, Wu H, Sun H, Zhou X, et al. Perioperative outcomes and mid-term effects in performing video-assisted thoracoscopic extended thymectomy for myasthenia gravis: subxiphoid versus right thoracic approaches. J Thorac Dis. 2020;12(4):1529–39. Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8464955","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":592615649,"identity":"8859273d-d17a-4064-a19c-4ad55b324a86","order_by":0,"name":"Lichen Zhang","email":"","orcid":"","institution":"Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Lichen","middleName":"","lastName":"Zhang","suffix":""},{"id":592615650,"identity":"078c7e77-1bd2-489e-b348-c036c5f48a3c","order_by":1,"name":"Zhengwei Huang","email":"","orcid":"","institution":"Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Zhengwei","middleName":"","lastName":"Huang","suffix":""},{"id":592615651,"identity":"05bd42d4-f04b-424a-9eb6-5f9c5ba09ed8","order_by":2,"name":"Jiajing Sun","email":"","orcid":"","institution":"Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Jiajing","middleName":"","lastName":"Sun","suffix":""},{"id":592615652,"identity":"2e10fc05-d547-4dba-9f85-9c5b2293efd9","order_by":3,"name":"Yingyu Zhu","email":"","orcid":"","institution":"Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Yingyu","middleName":"","lastName":"Zhu","suffix":""},{"id":592615653,"identity":"c5aee6fa-83c6-42ed-aa7c-e56ef0a999f6","order_by":4,"name":"Sheng Lu","email":"","orcid":"","institution":"Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Sheng","middleName":"","lastName":"Lu","suffix":""},{"id":592615654,"identity":"4a1c2970-d799-4d98-88fe-aa62eca7a221","order_by":5,"name":"Aotian Guo","email":"","orcid":"","institution":"Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Aotian","middleName":"","lastName":"Guo","suffix":""},{"id":592615655,"identity":"185f2881-77d3-425b-a209-4099aba2d4b3","order_by":6,"name":"Yifan Liu","email":"","orcid":"","institution":"Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Yifan","middleName":"","lastName":"Liu","suffix":""},{"id":592615656,"identity":"4d7d5bcf-0173-460c-9c76-8ffa2c93517b","order_by":7,"name":"Jiacong Liu","email":"","orcid":"","institution":"First Affiliated Hospital Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Jiacong","middleName":"","lastName":"Liu","suffix":""},{"id":592615657,"identity":"626df10b-0d21-4396-a418-0a70af834d83","order_by":8,"name":"Zhao Chen","email":"","orcid":"","institution":"Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University","correspondingAuthor":false,"prefix":"","firstName":"Zhao","middleName":"","lastName":"Chen","suffix":""},{"id":592615658,"identity":"5d818e35-4d71-41d1-85e4-841e235abac7","order_by":9,"name":"Zhengfu He","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA1klEQVRIiWNgGAWjYBACeWbmww8SDCTkGBgOALlsRGgxbGdLM3hQYGFMvBaG8zwGkg8+VCQ2gHnEaGFs5jEwADosfX7jGQOGD2WHGfhnN+DXws7MVgDyS25jwxkDxhnnDjNI3DlAyBbmDSBbcpsZzhgw87YdZjCQSCDgMrAaoMPYQFr+EqeFBawlgQekhZEYLYbNwEAGajGcwXCs4GDPuXQeiRsEtMjzHz788MefOnn5GYc3PvhRZi3HP4OQw+BA4gA4MnmIVQ8E/A0kKB4Fo2AUjIIRBQBrLEFftQcwPgAAAABJRU5ErkJggg==","orcid":"","institution":"Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University","correspondingAuthor":true,"prefix":"","firstName":"Zhengfu","middleName":"","lastName":"He","suffix":""}],"badges":[],"createdAt":"2025-12-28 09:38:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8464955/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8464955/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":103167020,"identity":"71f300f4-e831-4690-8c59-dfafa40537f8","added_by":"auto","created_at":"2026-02-22 12:43:28","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":165275,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFlowchart. VATS: Video-Assisted Thoracoscopic Surgery\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-8464955/v1/c9f3430662a4a7cacb3712ee.png"},{"id":103505125,"identity":"ee6a190b-5ad7-4953-8da8-294ca9c890ea","added_by":"auto","created_at":"2026-02-26 13:24:36","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":174387,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eComputed Tomography (CT) Scans Demonstrating A, B, and C. The maximum tumor diameter measured by CT scan was \u0026gt;5.0 cm and \u0026lt;10.0 cm.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-8464955/v1/45766fe98df519c684a08a50.png"},{"id":103167023,"identity":"9e86f85a-ef51-46bb-90de-5e0fd031b248","added_by":"auto","created_at":"2026-02-22 12:43:28","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":968941,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003e(A) (B): Surgical condition of thymoma resection through video-assisted thoracoscopic surgery (VATS) under the xiphoid process; (C): Resection of tumor, thymus, and adipose tissue (tumor size: 6.5cm); (D): Position of surgical incision and placement of drainage tube.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-8464955/v1/0c717f1fd609845772210a54.png"},{"id":103504767,"identity":"df0effe0-ccf1-4d9f-bef0-6fe34823656d","added_by":"auto","created_at":"2026-02-26 13:21:20","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":67455,"visible":true,"origin":"","legend":"\u003cp\u003eOverall survival (OS) outcomes\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-8464955/v1/f558311536854778945ad647.png"},{"id":103512785,"identity":"0d50a2aa-aad9-4b6e-a7aa-520443f73c7e","added_by":"auto","created_at":"2026-02-26 14:15:35","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2635734,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8464955/v1/2db59959-947d-4f3d-a6a0-257787bad8ab.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003ePerioperative Efficacy and Survival Prognosis of Subxiphoid Versus Intercostal Thoracoscopic Surgery for Large-Sized Thymoma: A Multicenter Retrospective Study \u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAnterior mediastinal tumors, including thymoma, teratoma, lipoma, and pericardial cyst, represent the most common type of mediastinal tumors. With the popularization of routine health screening and the widespread application of high-resolution spiral computed tomography (HRCT), the detection rate of these tumors has been significantly improved. Among anterior mediastinal tumors, thymoma is the most prevalent, and surgical resection remains the mainstay of treatment for this condition. Compared with traditional open thoracotomy, video-assisted thoracoscopic surgery (VATS) has gained widespread preference due to its minimally invasive nature, cosmetic benefits, reduced postoperative complications, alleviated pain, and accelerated recovery (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e).Currently, the intercostal VATS (IVATS) approach serves as the mainstream technique (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). In recent years, with the growing emphasis on enhanced recovery after surgery (ERAS), the subxiphoid VATS (SVATS) approach has emerged as an alternative. By placing the incision under the xiphoid process, SVATS can avoid intercostal nerve injury, thereby mitigating postoperative pain. Furthermore, this approach provides a superior surgical field of view, enabling clear visualization of the anatomical relationships between the tumor and critical structures such as the innominate vein and superior vena cava, thus attracting considerable attention among thoracic surgeons (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e).Nevertheless, robust evidence comparing the perioperative outcomes and long-term postoperative survival of patients undergoing SVATS versus IVATS for thymoma resection remains scarce. Therefore, this study aims to compare the clinical efficacy and postoperative survival outcomes between SVATS and IVATS in the treatment of anterior mediastinal tumors, explore the potential advantages of SVATS, and provide valuable insights for clinical decision-making.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis retrospective study enrolled patients with large thymomas who underwent subxiphoid or intercostal video-assisted thoracoscopic surgery (VATS) at Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, and The First Affiliated Hospital, Zhejiang University School of Medicine, between January 2018 and January 2023. A total of 138 patients were included, with 72 cases from Sir Run Run Shaw Hospital and 66 cases from The First Affiliated Hospital. Among them, 49 patients underwent subxiphoid VATS (16 cases from Sir Run Run Shaw Hospital and 33 cases from The First Affiliated Hospital), and 89 patients received intercostal VATS (56 cases from Sir Run Run Shaw Hospital and 33 cases from The First Affiliated Hospital), as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e This study was approved by the Clinical Research Ethics Committee of The First Affiliated Hospital, Zhejiang University School of Medicine (2022 IIT No. 1166) and Sir Run Run Shaw Hospital, Zhejiang University School of Medicine (2025 No. 1067). The study was conducted in compliance with the Declaration of Helsinki (revised 2013) and Good Clinical Practice (GCP) guidelines. All patients provided written informed consent for the use of their medical record data. All patients underwent contrast-enhanced computed tomography (CECT) to assess the size, location, and invasiveness of the lesions. Large thymomas were defined as tumors with a maximum diameter of \u0026ge;\u0026thinsp;5.0 cm and \u0026le;\u0026thinsp;10.0 cm on CECT scans (Figs.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eInclusion criteria: Age between 18 and 80 years. Thymoma with or without invasion of the pericardium, lung, or left innominate vein. Tumor diameter\u0026thinsp;\u0026ge;\u0026thinsp;5.0 cm and \u0026le;\u0026thinsp;10.0 cm. American Society of Anesthesiologists (ASA) physical status I\u0026ndash;II.Adequate organ function and cardiopulmonary reserve.\u003c/p\u003e \u003cp\u003eExclusion criteria:Absence of pretreatment imaging.Myasthenia gravis.Bleeding disorders.Clinically significant concurrent malignancies.Invasion of surrounding organs (except pericardium, lung, and left innominate vein).\u003c/p\u003e \u003cp\u003eDistant metastasis.Surgical indications:Adequate organ function and cardiopulmonary reserve to tolerate surgery.\u003c/p\u003e \u003cp\u003eAbsence of bleeding disorders.No invasion of surrounding organs (except pericardium, lung, and left innominate vein).No distant metastasis.\u003c/p\u003e \u003cp\u003eThe choice of surgical approach (subxiphoid VATS or intercostal VATS) was determined by the surgeon following thorough discussion. Data were collected through regular patient follow-ups or hospital visits, including baseline characteristics (age, body mass index BMI, sex, smoking status, alcohol consumption, comorbidities hypertension, diabetes, coronary heart disease, ASA status, tumor diameter,Masaoka-Koga and Pathology), intraoperative and postoperative outcomes (operation time, blood loss, intensive care unit ICU stay, drainage duration, drainage volume, postoperative hospital stay, duration of postoperative oral analgesics nonsteroidal anti-inflammatory drugs (NSAIDs), twice daily, R0 resection, and conversion to open surgery), and postoperative complications (pleural effusion, pneumothorax, pulmonary infection, chylothorax, subcutaneous emphysema, arrhythmia, postoperative hemorrhage, phrenic nerve paralysis, and reoperation). Follow-up was conducted for at least 36 months postoperatively.\u003c/p\u003e \u003cp\u003eThe primary endpoints included overall survival (OS), intraoperative blood loss, and duration of postoperative oral analgesic use. The secondary endpoints comprised postoperative drainage volume, operative time, postoperative length of hospital stay, and postoperative complications.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eSubxiphoid VATS Procedure:\u003c/h2\u003e \u003cp\u003eUnder general anesthesia with double-lumen endotracheal intubation, patients were placed in a supine position with legs apart for unilateral lung ventilation. The surgeon stood between the patient\u0026rsquo;s legs, and the assistant stood on the patient\u0026rsquo;s right side. A longitudinal incision was made at the lower edge of the xiphoid process as the observation port for a 10-mm, 30-degree rigid thoracoscope. The rectus abdominis muscle was dissected vertically, and the retrosternal space was bluntly dissected with the surgeon\u0026rsquo;s finger to expand the working space. Two operative ports were created at the midclavicular line crossing the bilateral costal arches for the insertion of an ultrasonic scalpel and thoracoscopic graspers. An artificial pneumomediastinum was established using carbon dioxide (CO2) insufflation, maintaining a pressure of 8 cm H2O to expand the retrosternal space and facilitate the procedure. The bilateral mediastinal pleura were opened to fully expose the intrathoracic vessels and phrenic nerves.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eIntercostal VATS Procedure:\u003c/h3\u003e\n\u003cp\u003eUnder general anesthesia with double-lumen endotracheal intubation, patients were placed in a semi-lateral decubitus position at 30\u0026ndash;45 degrees with the cranial and caudal sides tilted downward. This approach was performed through three ports: one observation port and two operative ports. The port selection depended on the tumor\u0026rsquo;s location, size, and the surgeon\u0026rsquo;s preference. During the procedure, the tumor and surrounding fatty tissue, as well as any involved organs, were resected. If the intercostal approach was not feasible, conversion to a transsternal approach or median sternotomy was performed. All specimens were retrieved in a specimen bag. A drainage tube was inserted into the thoracic cavity and removed when no air leakage was observed and the drainage volume was \u0026lt;\u0026thinsp;200 mL within 24 hours.performed through three ports: one observation port and two operative ports. The port selection depended on the tumor\u0026rsquo;s location, size, and the surgeon\u0026rsquo;s preference. During the procedure, the tumor and surrounding fatty tissue, as well as any involved organs, were resected. If the intercostal approach was not feasible, conversion to a transsternal approach or median sternotomy was performed. All specimens were retrieved in a specimen bag. A drainage tube was inserted into the thoracic cavity and removed when no air leakage was observed and the drainage volume was \u0026lt;\u0026thinsp;200 mL within 24 hours.\u003c/p\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eData analysis was performed using R software (version 4.2.3) and the ggplot2 package (version 3.3.5) for visualization. Statistical descriptions and inferences were conducted based on the distribution characteristics of the data. For quantitative data, the number of cases (including missing cases), minimum, maximum, mean, standard deviation, and median were reported. For qualitative data, the frequency and percentage of each variable level were presented. For time-to-event data, continuous variables were tested for normality using the Shapiro-Wilk test. Normally distributed data were expressed as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation, while non-normally distributed data were expressed as median\u0026thinsp;\u0026plusmn;\u0026thinsp;interquartile range (IQR). Based on normality, either the t-test or Wilcoxon rank-sum test was applied. Categorical data were expressed as frequencies and analyzed using Pearson\u0026rsquo;s chi-square test or Fisher\u0026rsquo;s exact test. A p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\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\u003eCharacteristics of the patients at baseline\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSubxiphoid approach(n\u0026thinsp;=\u0026thinsp;49)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eIntercostal approach(n\u0026thinsp;=\u0026thinsp;89)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge (years, mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e53.54\u0026thinsp;\u0026plusmn;\u0026thinsp;13.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e52.74\u0026thinsp;\u0026plusmn;\u0026thinsp;15.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.750\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBMI (kg/m2, mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24.55\u0026thinsp;\u0026plusmn;\u0026thinsp;2.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23.69\u0026thinsp;\u0026plusmn;\u0026thinsp;3.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.418\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSex, n (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.229\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30 (61.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e45 (50.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19 (38.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e44 (49.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSmoking status, n (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.474\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNever\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39 (79.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e66 (74.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEver\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10(20.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23(25.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eDrinking status, n (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.301\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNever\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43 (87.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e72 (80.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEver\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6 (22.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17 (19.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eASA status class, n (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.163\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18 (36.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30 (33.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eII\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e31 (63.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e59 (66.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eComorbidity, n (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17 (34.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21 (23.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.721\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTumor diameter (cm), mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD (range)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6.3\u0026thinsp;\u0026plusmn;\u0026thinsp;1.4(5.0\u0026ndash;10.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.24\u0026thinsp;\u0026plusmn;\u0026thinsp;1.3(5.0\u0026ndash;10.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.547\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMasaoka-Koga\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eⅠ\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15(30.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12(13.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.102\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eⅡA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10(20.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e31(34.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eⅡB\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14(28.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e27(30.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eⅢA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7(14.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16(18.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eⅢB\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3(6.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3(3.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePathology\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eThymic carcinoma, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11 (22.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13 (14.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.492\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType A thymic tumor, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (10.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9 (10.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType B1 thymic tumor, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (10.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10 (11.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType B2 thymic tumor, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7 (14.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22 (24.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType B3 thymic tumor, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (10.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4 (4.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType AB thymic tumor, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16 (32.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e31 (35)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e\u003cp\u003e\u003cstrong\u003eAbbreviations: BMI, Body Mass Index; ASA, American Society of Anesthesiologists; SD, Standard Deviation. Comorbidities included hypertension, diabetes, and coronary heart disease.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;2\u0026nbsp;\u003c/strong\u003eIntraoperative and postoperative outcomes of all patients\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"581\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 167px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 159px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSubxiphoid approach\u003c/strong\u003e\u003cstrong\u003e（\u003c/strong\u003e\u003cstrong\u003en=49\u003c/strong\u003e\u003cstrong\u003e）\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 148px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIntercostal approach\u003c/strong\u003e\u003cstrong\u003e（\u003c/strong\u003e\u003cstrong\u003en=89\u003c/strong\u003e\u003cstrong\u003e）\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 107px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 167px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOperation time (min, x \u0026plusmn; s)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 159px;\"\u003e\n \u003cp\u003e120.96 \u0026plusmn; 30.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 148px;\"\u003e\n \u003cp\u003e106.99 \u0026plusmn; 45.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 107px;\"\u003e\n \u003cp\u003e0.058\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 167px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBlood loss (ml, x \u0026plusmn; s)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 159px;\"\u003e\n \u003cp\u003e35.51 \u0026plusmn; 48.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 148px;\"\u003e\n \u003cp\u003e31.96 \u0026plusmn; 42.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 107px;\"\u003e\n \u003cp\u003e0.653\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 167px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDrainage dura- \u0026nbsp;tion (days, x \u0026plusmn; s)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 159px;\"\u003e\n \u003cp\u003e3.69 \u0026plusmn; 2.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 148px;\"\u003e\n \u003cp\u003e3.35 \u0026plusmn; 1.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 107px;\"\u003e\n \u003cp\u003e0.368\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 167px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVolume of drain- age (ml, x \u0026plusmn; s)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 159px;\"\u003e\n \u003cp\u003e437.09 \u0026plusmn; 410.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 148px;\"\u003e\n \u003cp\u003e662.71 \u0026plusmn; 690.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 107px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.017\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 167px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperative hospital stay \u0026nbsp; (days, x \u0026plusmn; s)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 159px;\"\u003e\n \u003cp\u003e5.14 \u0026plusmn; 2.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 148px;\"\u003e\n \u003cp\u003e4.61 \u0026plusmn; 1.86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 107px;\"\u003e\n \u003cp\u003e0.157\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 167px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDuration ofpostoperative \u0026nbsp;oral analgesics (days, x \u0026plusmn; s)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 159px;\"\u003e\n \u003cp\u003e2.11 \u0026plusmn; 1.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 148px;\"\u003e\n \u003cp\u003e3.88 \u0026plusmn; 1.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 107px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt; 0.001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 167px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eICU stay, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 159px;\"\u003e\n \u003cp\u003e4 (8.1%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 148px;\"\u003e\n \u003cp\u003e3 (3.3%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 107px;\"\u003e\n \u003cp\u003e0.220\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 167px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eR0 resection, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 159px;\"\u003e\n \u003cp\u003e49(100.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003e89(100.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 107px;\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 167px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eConversion to open surgery, \u0026nbsp;n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 159px;\"\u003e\n \u003cp\u003e0(0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003e0(0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 107px;\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;3\u0026nbsp;\u003c/strong\u003ePostoperative complications of all patients\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"511\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 193px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 142px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSubxiphoid approach\u003c/strong\u003e\u003cstrong\u003e（\u003c/strong\u003e\u003cstrong\u003en=49\u003c/strong\u003e\u003cstrong\u003e）\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 150px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIntercostal approach\u003c/strong\u003e\u003cstrong\u003e（\u003c/strong\u003e\u003cstrong\u003en=89\u003c/strong\u003e\u003cstrong\u003e）\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 193px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePleural effusion, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 142px;\"\u003e\n \u003cp\u003e5 (10.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 150px;\"\u003e\n \u003cp\u003e5 (5.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.322\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 193px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePneumothorax, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 142px;\"\u003e\n \u003cp\u003e0 (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 150px;\"\u003e\n \u003cp\u003e0 (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 193px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePulmonary infection, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 142px;\"\u003e\n \u003cp\u003e2 (4.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 150px;\"\u003e\n \u003cp\u003e0 (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.551\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 193px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eChylothorax, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 142px;\"\u003e\n \u003cp\u003e2 (4.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 150px;\"\u003e\n \u003cp\u003e0 (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.551\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 193px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSubcutaneous emphysema, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 142px;\"\u003e\n \u003cp\u003e1 (2.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 150px;\"\u003e\n \u003cp\u003e4 (4.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.463\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 193px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eArrhythmias, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 142px;\"\u003e\n \u003cp\u003e1 (2.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 150px;\"\u003e\n \u003cp\u003e0 (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.176\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 193px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePhrenic nerve palsy, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 142px;\"\u003e\n \u003cp\u003e0 (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 150px;\"\u003e\n \u003cp\u003e2 (2.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.290\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 193px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePostoperative bleeding, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 142px;\"\u003e\n \u003cp\u003e5 (10.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 150px;\"\u003e\n \u003cp\u003e7 (7.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.443\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"Results","content":"\u003cp\u003eBaseline Characteristics\u003c/p\u003e\n\u003cp\u003eFrom January 2018 to January 2023, a total of 247 patients were included in this study: 85 underwent subxiphoid VATS, and 162 underwent intercostal VATS. The baseline clinical characteristics of the two groups are shown in Table 1. There were no significant differences in age, BMI, sex, smoking status, alcohol consumption, comorbidities, ASA status, tumor diameter, or pathology and Masaoka-Koga between the two groups. (P \u0026gt; 0.05).\u003c/p\u003e\n\u003cp\u003eIntraoperative and Postoperative Outcomes\u003c/p\u003e\n\u003cp\u003eAs shown in Table 2, significant differences were observed in operative time (subxiphoid: 120.96 \u0026plusmn; 30.47 minutes, intercostal: 106.99 \u0026plusmn; 45.74 minutes, P = 0.058), drainage volume (subxiphoid: 437.09 \u0026plusmn; 410.75 mL, intercostal: 662.71 \u0026plusmn; 690.83 mL, P = 0.017), and duration of postoperative analgesic use (subxiphoid: 2.11 \u0026plusmn; 1.27 days, intercostal: 3.88 \u0026plusmn; 1.04 days, P \u0026lt; 0.001). No significant differences were found in blood loss (subxiphoid: 35.51 \u0026plusmn; 48.12 mL, intercostal: 31.96 \u0026plusmn; 42.21 mL, P = 0.653), drainage duration (subxiphoid: 3.69 \u0026plusmn; 2.41 days, intercostal: 3.35 \u0026plusmn; 1.99 days, P = 0.368), postoperative hospital stay (subxiphoid: 5.14 \u0026plusmn; 2.62 days, intercostal: 4.61 \u0026plusmn; 1.86 days, P = 0.127), or ICU admission (subxiphoid: 4 [8.1%], intercostal: 3 [3.3%], P = 0.220). The R0 resection rate was 100% for both approaches, and no patients required conversion to open surgery.\u003c/p\u003e\n\u003cp\u003eAs shown in Table 3, the overall complication rates were similar between the two groups. There were no significant differences in postoperative complications, including pleural effusion, pneumothorax, pulmonary infection, chylothorax, subcutaneous emphysema, arrhythmia, or phrenic nerve paralysis (P \u0026gt; 0.05).\u003c/p\u003e\n\u003cp\u003eOverall survival (OS) outcomes\u003c/p\u003e\n\u003cp\u003eOverall survival (OS) outcomes between the subxiphoid (SVATS) and intercostal (IVATS) groups are presented in Figure 4.(HR for death, 0.3 95% CI, 0.06 to 2.20; P=0.25)\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eCompared with traditional open thoracotomy, intercostal video-assisted thoracoscopic surgery (IVATS) features smaller lateral incisions, rendering the wounds cosmetically less conspicuous (5). Multiple studies have demonstrated that IVATS offers advantages such as reduced intraoperative blood loss, shorter chest tube indwelling time, shorter hospital stay, fewer postoperative complications, and comparable oncological outcomes(6, 7). Nevertheless, it has certain limitations, including difficulty in exposing the contralateral phrenic nerve, and intercostal nerve injury that may lead to chronic incision pain and numbness(8). The subxiphoid VATS (SVATS) approach was developed to avoid intercostal nerve injury and alleviate postoperative pain. Several studies have indicated that compared with the intercostal approach, SVATS results in milder postoperative pain and satisfactory cosmetic outcomes(9, 10). In our previous study, we compared the perioperative indicators among IVATS, SVATS, and open thoracotomy. For large anterior mediastinal masses without organ invasion, VATS was associated with less intraoperative blood loss and shorter duration of postoperative oral analgesic use than open thoracotomy(11). However, these studies focused on anterior mediastinal masses in general, encompassing benign lesions such as thymic cysts and hyperplasia as well as malignant tumors like thymoma, making the findings overly general.\u003c/p\u003e\n\u003cp\u003eThe present study specifically focused on malignant thymomas, comparing the perioperative efficacy and postoperative survival outcomes between SVATS and IVATS in the treatment of large thymomas. We found that compared with the intercostal approach, the subxiphoid approach was associated with less postoperative drainage volume, significantly shorter duration of postoperative oral analgesic use, and superior short-term perioperative efficacy, while there was no significant difference in 3-year survival outcomes between the two groups. Nevertheless, the operative time was longer in the SVATS group, which may be attributed to the limited experience of the surgical team and the inherent learning curve(10, 12, 13). SVATS can avoid intercostal nerve injury intraoperatively, thereby reducing postoperative pain. In addition, this approach provides a superior surgical field of view, enabling clear visualization of the anatomical relationships between the tumor and critical structures such as the innominate vein and superior vena cava(14, 15). This facilitates minimized tissue damage and potential intraoperative hemorrhage, contributing to less postoperative pain and reduced drainage volume in the short-term perioperative period.Thymomas are classified into pathological types A, AB, B1, B2, B3, and C (thymic carcinoma) (16, 17). Even type A and AB thymomas exhibit potential malignancy, so patient survival remains an important indicator for evaluating the two surgical approaches. Studies comparing IVATS and SVATS for anterior mediastinal tumors larger than 5 cm are scarce, particularly for large malignant thymomas(18-20).Therefore, we collected data from eligible patients treated at two large general hospitals between January 2018 and January 2023. The results showed no significant difference in survival outcomes between patients who underwent the two surgical procedures.\u003c/p\u003e\n\u003cp\u003eIn conclusion, compared with IVATS, SVATS for large thymomas is associated with less postoperative drainage volume and shorter duration of oral analgesic use, demonstrating advantages in short-term perioperative efficacy.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthical Statement\u003c/strong\u003e: The authors are accountable for all aspects of the work in ensuring\u003c/p\u003e\n\u003cp\u003ethat questions related to the accuracy or integrity of any part of the work are\u003c/p\u003e\n\u003cp\u003eappropriately investigated and resolved.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ethe Declaration of Helsinki (as revised in 2013). \u003cstrong\u003eThis study was approved by the Clinical Research Ethics Committee of the First Affiliated Hospital, Zhejiang University School of Medicine (2022 IIT No. 1166), Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University(2025 \u0026nbsp;No. 1067)\u003c/strong\u003e this retrospective analysis was waived\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eAuthor Contribution:\u003c/strong\u003e L.Z. (conceptualization, data curation, formal analysis, investigation, visualization, methodology, writing\u0026mdash;original draft). Z.H. (conceptualization, data curation, formal analysis, investigation, visualization, methodology,\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ewriting\u0026mdash;review and editing). J.S. (conceptualization, investigation, visualization, methodology, writing\u0026mdash;original draft). S.L. andY.Z.(conceptualization, data curation, investigation, visualization, methodology). A.G. and J.L.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e(conceptualization, investigation, visualization, methodology). X.L. Z.C.andY.L.(conceptualization, investigation, resources, supervision, validation). Z.H. (conceptualization, funding acquisition, investigation, resources, supervision, validation). All authors contributed to the article and approved the submitted version.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research was not founded.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eAdditional information\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analysed during this study are included in this published article [and its supplementary information files.\u003cstrong\u003e\u003c/strong\u003e\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eKamel MK, Villena-Vargas J, Rahouma M, Lee B, Harrison S, Stiles BM, et al. National trends and perioperative outcomes of robotic resection of thymic tumours in the United States: a propensity matching comparison with open and video-assisted thoracoscopic approaches\u0026dagger;. Eur J Cardiothorac Surg. 2019;56(4):762\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWu CF, Hsieh MJ, Liu HP, Gonzalez-Rivas D, Liu YH, Wu YC, et al. Management of post-operative pain by placement of an intraoperative intercostal catheter after single port video-assisted thoracoscopic surgery: a propensity-score matched study. J Thorac Dis. 2016;8(6):1087\u0026ndash;93.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGuerrero WG, Gonz\u0026aacute;lez-Rivas D. Multiportal video-assisted thoracic surgery, uniportal video-assisted thoracic surgery and minimally invasive open chest surgery-selection criteria. J Vis Surg. 2017;3:56.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLi Y, Huang Z, Han W, Yuan J, Xie R, Cheng G, et al. Subxiphoid and subcostal arch versus unilateral video-assisted thoracic surgery approaches to thymectomy for myasthenia gravis. Surg Today. 2023;53(1):12\u0026ndash;21.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAgatsuma H, Yoshida K, Yoshino I, Okumura M, Higashiyama M, Suzuki K, et al. Video-Assisted Thoracic Surgery Thymectomy Versus Sternotomy Thymectomy in Patients With Thymoma. Ann Thorac Surg. 2017;104(3):1047\u0026ndash;53.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSuda T, Hachimaru A, Tochii D, Maeda R, Tochii S, Takagi Y. Video-assisted thoracoscopic thymectomy versus subxiphoid single-port thymectomy: initial results\u0026dagger;. Eur J Cardiothorac Surg. 2016;49(Suppl 1):i54\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYe B, Tantai JC, Ge XX, Li W, Feng J, Cheng M, et al. Surgical techniques for early-stage thymoma: video-assisted thoracoscopic thymectomy versus transsternal thymectomy. J Thorac Cardiovasc Surg. 2014;147(5):1599\u0026ndash;603.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLiu Z, Yang R. Comparison of Subxiphoid and Intercostal Uniportal Thoracoscopic Thymectomy for Nonmyasthenic Early-Stage Thymoma: A Retrospective Single-Center Propensity-Score Matching Analysis. Thorac Cardiovasc Surg. 2021;69(2):173\u0026ndash;80.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYano M, Moriyama S, Haneda H, Okuda K, Kawano O, Oda R, et al. The Subxiphoid Approach Leads to Less Invasive Thoracoscopic Thymectomy Than the Lateral Approach. World J Surg. 2017;41(3):763\u0026ndash;70.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMao Y, Lan Y, Cui F, Deng H, Zhang Y, Wu X, et al. Comparison of different surgical approaches for anterior mediastinal tumor. J Thorac Dis. 2020;12(10):5430\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang L, Liu J, Xu W, Tang M, Wang Y, Lv W, et al. Three different surgical methods for large-sized anterior mediastinal tumors in real-world practice. BMC Cancer. 2024;24(1):1475.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWeng W, Li X, Meng S, Liu X, Peng P, Wang Z, et al. Video-assisted thoracoscopic thymectomy is feasible for large thymomas: a propensity-matched comparison. Interact Cardiovasc Thorac Surg. 2020;30(4):565\u0026ndash;72.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePennathur A, Qureshi I, Schuchert MJ, Dhupar R, Ferson PF, Gooding WE, et al. Comparison of surgical techniques for early-stage thymoma: feasibility of minimally invasive thymectomy and comparison with open resection. J Thorac Cardiovasc Surg. 2011;141(3):694\u0026ndash;701.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eShimomura M, Ishihara S, Okada S, Inoue M. Robotic subxiphoid-optical thymectomy. Interact Cardiovasc Thorac Surg. 2022;35(2).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHsu CP, Chuang CY, Hsu NY, Chen CY. Comparison between the right side and subxiphoid bilateral approaches in performing video-assisted thoracoscopic extended thymectomy for myasthenia gravis. Surg Endosc. 2004;18(5):821\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTateishi Y, Horita N, Namkoong H, Enomoto T, Takeda A, Kaneko T. Postoperative Radiotherapy for Completely Resected Masaoka/Masaoka-Koga Stage II/III Thymoma Improves Overall Survival: An Updated Meta-Analysis of 4746 Patients. J Thorac Oncol. 2021;16(4):677\u0026ndash;85.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFalkson CB, Vella ET, Ellis PM, Maziak DE, Ung YC, Yu E. Surgical, Radiation, and Systemic Treatments of Patients With Thymic Epithelial Tumors: A Systematic Review. J Thorac Oncol. 2023;18(3):299\u0026ndash;312.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOdaka M, Tsukamoto Y, Shibasaki T, Katou D, Mori S, Asano H, et al. Thoracoscopic thymectomy is a feasible and less invasive alternative for the surgical treatment of large thymomas. Interact Cardiovasc Thorac Surg. 2017;25(1):103\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLu Q, Zhao J, Wang J, Chen Z, Han Y, Huang L, et al. Subxiphoid and subcostal arch Three ports thoracoscopic extended thymectomy for myasthenia gravis. J Thorac Dis. 2018;10(3):1711\u0026ndash;20.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eQiu Z, Chen L, Lin Q, Wu H, Sun H, Zhou X, et al. Perioperative outcomes and mid-term effects in performing video-assisted thoracoscopic extended thymectomy for myasthenia gravis: subxiphoid versus right thoracic approaches. J Thorac Dis. 2020;12(4):1529\u0026ndash;39.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"thymomas, SVATS, IVATS, Multicenter Study","lastPublishedDoi":"10.21203/rs.3.rs-8464955/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8464955/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e \u003cb\u003eBackground\u003c/b\u003e \u003c/p\u003e \u003cp\u003eAnterior mediastinal tumors, including thymoma, teratoma, lipoma, and pericardial cyst, represent the most common subtype of mediastinal tumors, among which thymoma is the most prevalent malignant tumor in the anterior mediastinum. With the widespread application of high-resolution spiral computed tomography (HRCT) and the intensification of health screening, the detection rate of thymoma has been significantly improved. Surgical resection remains the cornerstone of treatment, with intercostal video-assisted thoracoscopic surgery (IVATS) serving as the mainstream approach. In recent years, under the principles of enhanced recovery after surgery (ERAS), the subxiphoid VATS (SVATS) approach has attracted considerable attention. Nevertheless, robust evidence-based data comparing its perioperative efficacy and postoperative survival outcomes with the traditional intercostal approach for anterior mediastinal tumor resection remains lacking.\u003c/p\u003e \u003cp\u003e \u003cb\u003eMethods\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThis retrospective study included 138 patients with thymomas (5.0\u0026ndash;10.0 cm) who underwent subxiphoid or intercostal VATS at two hospitals from January 2018 to January 2023. Clinical data, intraoperative and postoperative outcomes, complications and overall survival were analyzed. The primary endpoints included overall survival (OS), intraoperative blood loss, and duration of postoperative oral analgesic use. The secondary endpoints comprised postoperative drainage volume, operative time, postoperative length of hospital stay, and postoperative complications.\u003c/p\u003e \u003cp\u003e \u003cb\u003eResults\u003c/b\u003e \u003c/p\u003e \u003cp\u003eAfter matching, 138 patients were analyzed, drainage volume (subxiphoid: 437.09\u0026thinsp;\u0026plusmn;\u0026thinsp;410.75 mL, intercostal: 662.71\u0026thinsp;\u0026plusmn;\u0026thinsp;690.83 mL, P\u0026thinsp;=\u0026thinsp;0.017), and duration of postoperative analgesic use (subxiphoid: 2.11\u0026thinsp;\u0026plusmn;\u0026thinsp;1.27 days, intercostal: 3.88\u0026thinsp;\u0026plusmn;\u0026thinsp;1.04 days, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Overall survival were prestened (HR for death, 0.3 95% CI, 0.06 to 2.20; P\u0026thinsp;=\u0026thinsp;0.25).\u003c/p\u003e \u003cp\u003e \u003cb\u003eConclusion\u003c/b\u003e \u003c/p\u003e \u003cp\u003e Compared with IVATS, SVATS for large thymomas is associated with less postoperative drainage volume and shorter duration of oral analgesic use, demonstrating advantages in short-term perioperative efficacy.\u003c/p\u003e","manuscriptTitle":"Perioperative Efficacy and Survival Prognosis of Subxiphoid Versus Intercostal Thoracoscopic Surgery for Large-Sized Thymoma: A Multicenter Retrospective Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-22 12:43:24","doi":"10.21203/rs.3.rs-8464955/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewersInvited","content":"","date":"2026-02-17T08:49:41+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-16T12:37:07+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-01-27T09:38:36+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-25T07:33:04+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Gastroenterology","date":"2026-01-25T07:27:10+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"8736cc19-96ab-4ab8-be49-c87034041c6c","owner":[],"postedDate":"February 22nd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-02-22T12:43:24+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-22 12:43:24","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8464955","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8464955","identity":"rs-8464955","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}