A Comparative Study of Clinical Outcomes According to the Level of Inferior Mesenteric Vein Ligation in Laparoscopic Colorectal Cancer Surgery

A Comparative Study of Clinical Outcomes According to the Level of Inferior Mesenteric Vein Ligation in Laparoscopic Colorectal Cancer Surgery | 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 A Comparative Study of Clinical Outcomes According to the Level of Inferior Mesenteric Vein Ligation in Laparoscopic Colorectal Cancer Surgery Dae Ro Lim, Nahyeon Park, Go Won Park, Jung Kul Kuk, Eung Jin Shin This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8495808/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Propose : In colorectal cancer surgery, both the inferior mesenteric artery (IMA) and inferior mesenteric vein (IMV) are routinely ligated. While the optimal level of IMV has been extensively studied, evidence regarding the appropriate level of IMV ligation remains limited. This study aimed to evaluate clinical and oncologic outcomes according to the level of IMV ligation in laparoscopic colorectal cancer surgery. Materials and Methods: Between January 2016 and August 2018, a total 223 patients who underwentlaparoscopic curative resection for colorectal cancer were retrospectively identified from an institutional database. Patients were divided into two groups according to the level of IMV ligation: high ligation (n=138) vs. low ligation (n=85). Clinical characteristics, perioperative complications, and long-term oncologic outcomes were compared between the two groups. Results: With a median follow up of 49.4 months, the overall postoperative complication rate did not differ significantly between the high and low IMV ligation groups (12.3% vs. 12.0%, p=0.902). The rate of major complications, including anastomotic leakage, ischemia, and stenosis, was also comparable (2.2% vs. 1.2%, p=0.602). The mean length of hospital stay was similar between the two groups (9.3 vs. 9.1 days, P=0.590). The 5-years disease free survivalrate were 88.4% in the high ligation group and 88.5% in the low ligation group (p = 0.743), while the 5-years overall survival ratewere 92.7% and 88.5%, respectively (p = 0.562). Conclusion: Based on present data, the level of IMV ligation – whether high or low – was not associated with significant differences in short-term postoperative outcomes or long-term oncologic results in laparoscopic anterior and low anterior resection for colorectal cancer. Colorectal cancer Inferior mesenteric vein Laparoscopic surgery Figures Figure 1 Figure 2 Introduction Surgery remains the cornerstone of curative treatment for colorectal cancer, and laparoscopic colorectal cancer surgery has become a standard approach, providing oncologic outcomes comparable to open surgery while offering the benefits of reduced postoperative pain, faster recovery, and shorter hospital stay [ 1 – 3 ]. During laparoscopic anterior resection or low anterior resection, vascular ligation plays a critical role in achieving adequate oncologic clearance and facilitating safe mobilization of the colon. In colorectal cancer surgery, both the inferior mesenteric artery (IMA) and inferior mesenteric vein (IMV) ligation are routinely ligated during mesenteric mobilization. While the optimal level of IMA ligation has been extensively investigated, including its impact on oncologic outcomes and anastomotic perfusion, the clinical significance of the level of IMV ligation remains less well defined. Anatomically, the IMV courses in close proximity to the pancreas and splenic vessels, and its level of ligation may influence operative complexity, the extent of mesocolic mobilization, and risk of injury to adjacent structures. High ligation of the IMV at the level of the inferior border of the pancreas has been advocated to facilitate splenic flexure mobilization and to reduce mesenteric tension, potentially allowing for a tension-free colorectal anastomosis. Conversely, low ligation of the IMV near the origin of the IMA may simplify the operative procedure and reduce the risk of pancreatic or collateral vessel injury [ 4 – 5 ]. In addition, preservation of venous drainage through low IMV ligation has been proposed to reduce venous congestion and bowel wall edema at the anastomotic site. Despite these theoretical considerations, available evidence comparing high and low IMV ligation is limited, and previously published studies have reported inconsistent results regarding perioperative outcomes and oncologic adequacy [ 6 – 11 ]. Moreover, most prior investigations have primarily focused on arterial ligation strategies, with comparatively little attention given to the clinical implications of IMV ligation level. As a result, the optimal approach to IMV management during laparoscopic colorectal cancer surgery remains controversial, and clinical guidance is lacking. Therefore, the present study aimed to compare perioperative outcomes, postoperative complications, and long-term oncologic outcomes according to the level of IMV ligation in patients undergoing laparoscopic colorectal cancer surgery. By evaluating the clinical impact of high versus low IMV ligation, this study seeks to support informed surgical decision-making regarding IMV management. Materials and Methods Patients Between January 2016 and August 2018, a total 223 patients who underwent laparoscopic assisted low anterior resection with double stapling technique for rectal adenocarcinoma were retrospectively identified from an institutional database. Patients with synchronous and metachronous cancer were excluded. Patient with stage IV disease were also excluded from the analysis. All clinical and pathological data were reviewed retrospectively. Preoperative evaluation included colonoscopy with biopsy and staging studies using computed tomography of the chest, abdomen, and pelvis. Positron emission tomography scans were performed selectively when clinically indicated. All patients underwent curative resection. Patients with clinically staged T3 or T4 tumors and/or node-positive disease received long-course neoadjuvant chemoradiation therapy consisting of fluorouracil-based chemotherapy and a total radiation dose of 50.4 Gy. Surgical resection was performed 6–8 weeks after completion of neoadjuvant therapy. Patients were followed until December 2022 or until death, if it occurred earlier. Based on the level of IMV ligation, patients were divided into two groups: high IMV ligation (n = 138) and low IMV ligation (n = 58) (Fig. 1 .). The two groups were compared with respect to demographic characteristics, perioperative outcomes, postoperative morbidity, and pathological and oncologic outcomes. Definition of IMV ligation and Surgery All surgical procedures were performed laparoscopically by experienced colorectal surgeons using a standardized technique. Laparoscopic anterior resection or low anterior resection with total mesorectal excision was performed according to tumor location, following established oncologic principles. The level of IMV ligation was classified base on the anatomical site of division. Low IMV ligation was defined as division of the IMV near the root of the IMA, corresponding to the level of high IMA ligation, in which the IMA was divided approximately 1-2cm from its origin. High IMV ligation was defined as division of the IMV at a more proximal level, near the inferior border of the pancreas and close to the ligament of Treitz (Fig. 1 .). The choice of IMV ligation level was determined by the operating surgeon based on intraoperative anatomical considerations and the extent of colonic mobilization required. Statistical Analysis All statistical analyses were performed using SAS software version 9.1.3 (SAS Institute Inc., Cary, NC, USA) and SPSS software version 24.0 (SPSS Inc., Chicago, IL, USA). Categorical variables were analyzed using the chi-square test or Fisher’s exact tests, as appropriate. Continuous variables were analyzed using Student’s t test or the Mann-Whitney U test depending on data distribution. Overall survival (OS) and disease-free survival (DFS) were estimated using the Kaplan-Meier method and compared between groups using the log-rank test. To identify independent prognostic factors for DFS, univariate and multivariate analyses performed using the Cox proportional hazards regression mode. Variables with clinical relevance and/or those with a p-value < 0.10 in univariate analysis were entered into the multivariate model. Proportional hazards assumptions were assessed using log-minus-log plots and/or Schoenfeld residuals. Results are presented as hazard ratios (HRs) with 95% confidence intervals (Cis). A two-sided p-value < 0.05 was considered statistically significant. Ethics This study was approved by the institutional Review Board of Soonchunhyang University Bucheon Hospital (IRB No: SCHBC2025-0…..). Given the retrospective study design and anonymized data collection, the requirement for informed consent was waived. Results Patients characteristics Patient characteristics were compared between the high IMV ligation group (n = 138) and low IMV ligation group (n = 85) (Table 1 .). There were no significant differences between the two groups with respect to mean age, sex distribution, height, weight, body mass index (BMI), and ASA scores, or history of previous abdominal surgery. The rate of neoadjuavnt chemoradiation therapy rate was significantly higher in the high IMV ligation group than in the low IMV ligation group (23.2% vs. 10.6%, p = 0.018). The rate of adjuvant chemotherapy did not differ significantly between the two groups (Table 1 .). Table 1 Patient characteristics (n = 223) High IMV ligation (n = 138) (%) Low IMV ligation (n = 85) (%) p value Age(mean \(\:\pm\:\:\text{S}\text{D},\:\left(\text{r}\text{a}\text{n}\text{g}\text{e}\right)\) ) (year) 63.4 ± 9.9(32–85) 63.8 ± 12.6(33–89) 0.820 Sex, n (%) 0.634 Male 84(60.9%) 49(57.6%) Female 54(39.1%) 36(42.4%) Weight(mean \(\:\pm\:\:\text{S}\text{D},\:\left(\text{r}\text{a}\text{n}\text{g}\text{e}\right)\) ) (kg) 62.6 ± 11.0 (38.0-100.4) 62.0 ± 11.0 (32.0-86.9) 0.638 Height(mean \(\:\pm\:\:\text{S}\text{D},\:\left(\text{r}\text{a}\text{n}\text{g}\text{e}\right)\) ) (cm) 161.3 ± 8.4 (136.5-178.3) 160.4 ± 9.3 (141.1-181.4) 0.160 BMI(mean \(\:\pm\:\:\text{S}\text{D},\:\:\left(\text{r}\text{a}\text{n}\text{g}\text{e}\right)\) ) (Kg/m 2 ) 23.9 ± 3.2(16.8–36.2) 24.0 ± 3.3(14.6–33.0) 0.799 ASA score, n (%) 0.205 1 70(50.7%) 36(42.4%) 2 57(41.3%) 45(52.9%) 3 11(8.0%) 4(4.7%) Previous abdomen surgery 0.385 Yes 10(7.2%) 9(10.6%) No 128(92.8%) 76(89.4%) Neoadjuvant chemoradiation therapy 0.018 Yes 32(23.2%) 9(10.6%) No 106(76.8%) 76(89.4%) Adjuvant chemotherapy 0.112 Yes 58(42.0%) 45(52.9%) No 80(58.0%) 40(47.1%) Pathologic results Pathologic staging was performed according to the American Joint Committee on Cancer (AJCC) 8th edition. There was no significant difference in overall TNM stage distribution between the two groups (p = 0.585). Similarly, pT stage and pN stage distributions were comparable. Histological grades of differentiation, lymphovascular invasion rate, perineural invasion rate, proximal resection margin, distal resection margin, and tumor size did not differ significantly between the high and low IMV ligation groups. The mean number of harvested lymph nodes was also comparable between the two groups (Table 2 .). Table 2 Postoperative pathologic outcomes (n = 223) High IMV ligation (n = 138) (%) Low IMV ligation (n = 85) (%) p value pTNM stage, no. (%) CR 4(2.9%) 2(2.4%) 0.585 I 35(25.4%) 25(29.4%) IIa IIb IIIa IIIb IIIc 48(34.8%) 2(1.4%) 8(5.8%) 35(25.4%) 6(4.3%) 22(25.9%) 2(2.4%) 6(7.1%) 19(22.4%) 9(10.6%) pT/ypT stage, no. (%) CR/0 4(2.9%) 2(2.4%) 0.489 1 27(19.6%) 16(18.8%) 2 21(15.2%) 15(17.6%) 3 80(58.0%) 46(54.1%) 4 6(4.3%) 6(7.1%) pN/ypN stage, no. (%) 0.211 0 1a 1b 1c 2a 2b 89(64.5%) 13(9.4%) 7(5.1%) 3(2.2%) 15(10.9%) 11(8.0%) 50(58.8%) 9(10.6%) 14(16.5%) 0(0.0%) 4(4.7%) 8(9.4%) Grade of differentiation, no. (%) 0.709 Well 13(9.4%) 11(12.9%) Moderate 117(84.8%) 69(81.2%) Poor 8(5.8%) 5(5.9%) Mucinous 0(0.0%) 0(0.0%) Harvested no. of lymph nodes, (mean \(\:\pm\:\:\) SD, range), (No) 17.0 ± 9.3 16.7 ± 7.0 0.065 Lymphovascular invasion 0.856 No 109(79.0%) 68(80.0%) Yes Perineural invasion No Yes 29(21.0%) 83(60.1%) 55(39.9%) 17(20.0%) 45(52.9%) 40(47.1%) 0.291 PRM, (mean \(\:\pm\:\:\) SD, range), (cm) 9.7 ± 7.5 9.8 ± 5.4 0.711 DRM, (mean \(\:\pm\:\:\) SD, range), (cm) 4.3 ± 3.9 3.9 ± 1.9 0.121 Mass size 3.8 ± 2.1 3.6 ± 1.8 0.108 PRM: proximal resection margin, DRM: Distal resection margin Peri-operative outcomes The mean operation time was significantly longer in the high IMV ligation group than in the low IMV ligation group (198.6 ± 55.5 minutes vs. 180.8 ± 67.7, p = 0.019). Mean intraoperative blood loss did not differ significantly between the two group (100.5 ml vs. 96.2 ml, p = 0.429). The mean length of hospital stay was 9.3 days in high IMV ligation group and 9.1 days in low IMV ligation group, with no significant difference (p = 0.590). The overall postoperative morbidity comparable between the two groups (12.3% vs. 12.0%, p = 0.902). Anastomotic leakage occurred in 2.2% (n = 3) of patients in the high IMV ligation group and 1.2% (n = 1) of patients in the low IMV ligation group, with no significant difference (p = 0.602). Rates of intestinal obstruction or ileus were 5.1% (n = 7) in the high ligation group and 1.2% (n = 1) in the low ligation group. There was no significant difference in postoperative mortality between the two groups (Table 3 .). Table 3 Peri-postoperative outcomes at High IMV versus Low IMV ligation groups (n = 223). High IMV ligation (n = 138) (%) Low IMV ligation (n = 85) (%) p value Operation time (min) 198.6 ± 55.5 180.8 ± 67.7 0.019 Blood loss (ml) 100.5 ± 114.3 96.2 ± 148.5 0.429 Length of hospital stay (day) 9.3 ± 2.6(7–24) 9.1 ± 2.9(7–27) 0.590 Time to sips of water (day) 3.2 ± 0.4(3–6) 3.4 ± 0.9(3–10) 0.000 Time to liquid diet (day) Time to soft diet (day) 5.3 ± 1.2(3–14) 6.3 ± 1.2(4–15) 5.2 ± 1.3(4–12) 6.2 ± 1.3(4–13) 0.557 0.643 Total Morbidity (n; %) Urinary disfunction 17(12.3%) 2(1.4%) 10(12.0%) 2(2.4%) 0.902 Pulmonary disease Ileus/intestinal obstruction Late intestinal obstruction Wound infection Anastomosis site leakage Major leakage Minor leakage Delayed leakage Anal stenosis Bleeding Ischemia Sepsis 2(1.4%) 7(5.1%) 1(0.7%) 1(0.7%) 3 (0.0%) 1(0.7%) 1(0.7%) 1(0.7%) 1(0.7%) 0(0.0%) 0(0.0%) 0(0/0%) 2(2.4%) 1(1.2%) 1(1.2%) 0(0.0%) 1(1.2%) 0(0.0%) 1(1.2%) 0(0.0%) 1(1.2%) 0(0.0%) 1(1.2%) 1(1.2%) Total Mortality 0(0.0%) 1(1.2%) NS Oncologic outcomes and Recurrent patterns after surgery The mean follow-up duration was 49.4 months. There was no significant differences between the two groups in 5-year overall survival, disease-free survival, local recurrence, or distant recurrence rate. The 5-year overall survival rate was 92.7% in high IMV ligation group and 88.5% in low IMV ligation group (p = 0.562). The 5-year disease free survival rate was 88.4% in high IMV ligation group and 88.5% in low IMV ligation group (p = 0.743) (Fig. 2 .). The overall recurrence rate was 13.0% in high IMV ligation group and 10.6% in low IMV ligation group (p = 0.601). Local recurrence occurred in 0.7% of patients in the high IMV ligation group and 2.4% in the low IMV ligation group. Distant recurrence rates were 12.3% and 8.2%, respectively. Recurrent patterns did not differ significantly different between the two groups (Table 4 .). Table 4 Recurrence pattern of IMV high versus low ligation groups (n = 223). High IMV ligation (n = 138) (%) Low IMV ligation (n = 85) (%) p value Total Number of Recurrence 18(13.0%) 9(10.6%) 0.601 Systemic recurrence 17(12.3%) 7(8.2%) NS Lung 7(5.1%) 4(4.7%) Liver 4(2.9%) 3(3.5%) Paraaortic node 4(2.9%) 0(0.0%) Bone Peritoneum 0(0.0%) 2(1.4%) 0(0.0%) 0(0.0%) Local recurrence 1(0.7%) 2(2.4%) NS Pelvic side wall 0(0.0%) 1(1.2%) Perineum Rectal fossa Anastomosis site 0(0.0%) 1(0.7%) 0(0.0%) 0(0.0%) 0(0.0%) 1(1.2%) Univariate and multivariate analysis of prognostic factors for 5-year disease free survival Univariate and multivariate Cox proportional hazards regression analyses were performed to identify prognostic factors for 5-year disease free survival. In univariate analysis, sex, age, BMI, tumor size, N stage, histological grade, perineural invasion, and neoadjuvant chemoradiation therapy were not significantly associated with disease free survival. T stage, lymphovascular invasion, and adjuvant chemotherapy were significantly associated with disease-free survival in univariate analysis. In multivariate analysis, T stage remained an independent prognostic factor. The level of IMV ligation was not associated with disease-free survival in either univariate (odds ratio 0.87; 95% confidence interval 0.39–1.96; p = 0.744) or multivariate analysis (odds ratio 0.88; 95% confidence interval 0.39–1.99; p = 0.764) (Table 5 .). Table 5 Univariate and multivariate Cox proportional hazards regression analyses of prognostic factor for disease free survival Univariate analysis Multivariate analysis Factors HR 95% CI P-value HR 95% CI P-value Age, years 0.31 0.04–2.49 0.272 (< 70 vs. ≥70) Sex 0.84 0.38–1.85 0.665 (Male vs. Female) BMI 1.35 0.62–2.94 0.447 (< 25 vs. ≥25) Tumor size, cm 1.25 0.56–2.81 0.584 (< 5 vs. ≥5) T stage 5.42 1.63–18.04 0.006 0.23 0.06–0.85 0.027 (T1-2 vs. T3-4) N stage 1.59 0.74–3.44 0.239 (N0 vs. N1-2) Histological grade 2.83 0.85–9.44 0.091 (Well-mod. vs. others) Lymphovascular invasion 2.27 1.01–5.10 0.046 0.61 0.26–1.44 0.259 (present vs. absent) Perineural invasion 1.93 0.89–4.20 0.099 (present vs. absent) Neoadjuvant chemoradiation 1.60 0.67–3.82 0.285 (Yes vs. No) Adjuvant chemotherapy 2.75 1.10–6.85 0.030 1.31 0.46–3.71 0.609 (Yes vs. No) Inferior mesenteric vein 0.87 0.39–1.96 0.744 0.88 0.39–1.99 0.764 (high ligation vs. low ligation) Discussion In the present study, we evaluated the clinical impact of the level of IMV ligation in laparoscopic colorectal cancer surgery. Our results demonstrated that the level of IMV ligation-whether high or low-was not associated with significant differences in postoperative morbidity or long-term oncologic outcomes. These findings suggest that both high and low IMV ligation strategies can be safely applied without compromising short term surgical safety or oncologic adequacy. High ligation of the IMV has traditionally been advocated to facilitate splenic flexure mobilization and to achieve a tension-free anastomosis, particularly in patients requiring low pelvis anastomosis. In the present study, high IMV ligation was associated with a longer operative time but was not linked to increased blood loss, postoperative complications, or anastomotic leakage. These results indicate that high IMV ligation can be performed safely in the laparoscopic setting when adequate surgical expertise is available, despite its potential technical complexity. Conversely, low ligation of the IMV has been proposed to preserve venous drainage of the remnant colon, thereby reducing venous congestion and bowel wall edema at the anastomotic site. Another potential advantages of low IMV ligation is avoidance of injury to adjacent collateral vessels [ 11 ]. Anatomical studies using computed tomography angiography have reported that the Arc of Riolan may course along the inferior border of the pancreas and cross anterior to the IMV in approximately 10–40% of patients [ 12 – 13 ]. These vessels may be encountered during skeletonization of the IMV for high ligation, posing a potential risk of inadvertent injury. Previous studies have emphasized the importance of careful dissection to avoid collateral vessels damage during IMV ligation [ 13 ]. Although low IMV ligation did not significantly reduce the rate of anastomotic leakage in the present study, a trend toward fewer anastomosis related complications was observed. This finding supports the theoretical advantage of preserving venous outflow and suggests that low IMV ligation may be considered in selected patients who are at higher risk for anastomotic complications. From an oncologic standpoint, both IMV ligation strategies achieved comparable lymph node yields and pathological outcomes. In addition, no significant differences were observed in disease-free or overall survival between the two group. These findings suggest that, unlike arterial ligation, the level of IMV ligation may play a limited role in determining oncologic radicality, provided that standard oncologic principles including adequate mesocolic excision and lymphadenectomy are followed. Our results therefore support an individualized approach to IMV ligation based on patient anatomy, tumor location, and the extent colonic mobilization required, rather than strict adherence to a single standardized technique. Several limitations of this study should be acknowledged. First, the retrospective design introduces the possibility of selection bias, as the choice of IMV ligation level was determined by surgeon preference rather than randomization. Second, although the sample size was relatively large compared with previous reports, the study may still be underpowered to detect small differences in rare complications, such as anastomotic leakage. Third, this study is single institution study which may limit the generalizability of the findings. Finally, although long-term oncologic outcomes were evaluated, residual confounding factors inherent to retrospective analyses cannot be completely excluded. Future prospective, multi-institutional studies are warranted to further clarify the optimal strategy for IMV ligation in laparoscopic colorectal cancer surgery. Despite these limitations, this study provides clinically relevant evidence regarding IMV ligation strategy in laparoscopic colorectal cancer surgery. The findings suggest that both high and low IMV ligation can be safely performed with comparable short term and oncologic outcomes. Therefore, the choice of IMV ligation level may be tailored according to individual patient anatomy, tumor location, and the extent of colonic mobilization required. Conclusion In laparoscopic colorectal cancer surgery, the level of IMV ligation was not associated with significant differences in short term postoperative outcomes or oncologic adequacy. Both high and low IMV ligation strategies achieved comparable surgical safety and pathological results when standard oncologic principles were followed. These findings suggest that routine high ligation of the IMV may not be mandatory in all cases. Instead, the IMV ligation level can be individualized according to patient anatomy, tumor location, and the extent of colonic mobilization required to achieve a safe, tension-free anastomosis. Declarations Author Contribution Dae Ro Lim worte the main manuscript text. Dae Ro Lim, Nahyeon Park and Go Won Park prepared a table and a figure. Dae Ro Lim, Jung Kul Kuk and Eung Jin Shin collected and analyzed data. Acknowledgements All authors declare no conflict of interest in this work. Informed consent was not required due to the retrospective design. This work was supported by the Soonchunhyang University Research Fund. References Fleshman J, Sargent DJ, Green E, Anvari M, Stryker SJ, Beart RW Jr, et al. Laparoscopic colectomy for cancer is not inferior to open surgery based on 5-year data from the COST Study Group trial. Ann Surg 2007;246:655–62. Jayne DG, Thorpe HC, Copeland J, Quirke P, Brown JM, Guillou PJ. Five-year follow-up of the Medical Research Council CLASICC trial of laparoscopically assisted versus open surgery for colorectal cancer. Br J Surg 2010;97:1638–45. COLOR Study Group. COLOR: a randomized clinical trial comparing laparoscopic and open resection for colon cancer. Dig Surg 2000;17:617–22. A C Lowry, C L Simmang, P Boulos, K C Farmer, P J Finan, M Killinhback, et al. Consensus statement of definitions for anorectal physiology and rectal cancer: report of the tripartite consensus conference on definitions for anorectal physiology and rectal cancer, Washington, D.C., May 1, 1999. Dis Colon Rectum. 2001;44:915-9. Cirocchi R, Trastulli S, Farinella E, Desiderio J, Vettoretto N, Paris A, et al. High tie versus low tie of the inferior mesenteric artery in colorectal cancer: a RCT is needed. Surg Oncol. 2012;21:111–23. Lange MM, Buunen M, van de Velde CJ, Lange JF. Level of arterial ligation in rectal cancer surgery: low tie preferred over high tie: a review. Dis Colon Rectum. 2008;51:1139–45. Zeng J, Su G. High ligation of the inferior mesenteric artery during sigmoid colon and rectal cancer surgery increase the risk of anastomotic leakage: a meta-analysis. World J Surg Oncol. 2018;16:157. Kim K, An S, Kim MH, Jung JH, Kim Y. High versus low ligation of the inferior mesenteric artery in colorectal cancer surgery: a systematic review and meta-analysis. Medicina(Kaunas). 2022;58:1143. Girard E, Trilling B, Rabattu PY, Taton N, Robert Y, Chaffanjon P, et al. Level of inferior mesenteric artery ligation in low rectal cancer surgery: high tie preferred over low tie. Tech coloproctol. 2019;23:267–71. Yang Y, Wang G, He J, Zhang J, Xi J, Wang F. High tie versus low tie of the inferior mesenteric artery in colorectal cancer: a meta-analysis. Int J Surg. 2018;52:20–24. Garcia-Granero A, Pellino G, Frasson M, Primo Romaguera V, Fletcher-Sanfeliu D, Blasco Serra A, et al. Possible effects of height of ligation of the inferior mesenteric vein on venous return of the colorectal anastomosis: the venous trunk theory. Tech Coloproctol. 2019;23:799–800. S Bonnet, A Berger, N Hentati, B Abid, J-M Chevallier, P Wind, et al. High tie versus low tie vascular ligation of the inferior mesenteric artery in colorectal cancer surgery: impact on the gain in colon length and implications on the feasibility of anastomoses. Dis Colon Rectum. 2012;55:515–21. Al-Asari SF, Lim D, Min BS, Kim NK. The relation between inferior mesenteric vein ligation and collateral vessels to splenic flexure: anatomical landmarks, technical precautions and clinical significance. Yonsei Med J. 2013;54:1484–90. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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-8495808","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":573373157,"identity":"58c1af28-869e-4dc6-b0f6-2c290a7ba2f7","order_by":0,"name":"Dae Ro Lim","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA10lEQVRIiWNgGAWjYBACPmYGBgkQg5+BgQ0qxoZHPUgapkWygWgtDFAtBgeI1sLOnXjjR8U9OePzh589ulHDIM/fwJb2Ab/DeDdb9pwpNja7kWZunHOMwXDGAbbDMwho2SbB25aQuO0GD5t0bgMD4wYG9mb8DgNqkfz7LyFxc/8ZsBZ7orRI8zYkJG5gyAFrATLYDhPSstla5liCscSNNDPpnGMSyTMOsyXj1cLPf3bjzTc1CXL8/YefSefU2Nj2t7cZ49WCDoBxxEyShlEwCkbBKBgF2AAA6XU76u1gvfAAAAAASUVORK5CYII=","orcid":"","institution":"Soonchunhyang University College of Medicine, Soonchunhyang University Bucheon Hospital","correspondingAuthor":true,"prefix":"","firstName":"Dae","middleName":"Ro","lastName":"Lim","suffix":""},{"id":573373158,"identity":"0aeffbd8-d32d-4387-95d6-f2b5695a4317","order_by":1,"name":"Nahyeon Park","email":"","orcid":"","institution":"Soonchunhyang University College of Medicine, Soonchunhyang University Bucheon Hospital","correspondingAuthor":false,"prefix":"","firstName":"Nahyeon","middleName":"","lastName":"Park","suffix":""},{"id":573373159,"identity":"016f45e3-08b7-42c0-b046-4229cf9a3fa7","order_by":2,"name":"Go Won Park","email":"","orcid":"","institution":"Soonchunhyang University College of Medicine, Soonchunhyang University Bucheon Hospital","correspondingAuthor":false,"prefix":"","firstName":"Go","middleName":"Won","lastName":"Park","suffix":""},{"id":573373160,"identity":"d61d4c34-0a97-4686-aad1-18d40e195df7","order_by":3,"name":"Jung Kul Kuk","email":"","orcid":"","institution":"Soonchunhyang University College of Medicine, Soonchunhyang University Bucheon Hospital","correspondingAuthor":false,"prefix":"","firstName":"Jung","middleName":"Kul","lastName":"Kuk","suffix":""},{"id":573373161,"identity":"bb2058bb-16de-4ff2-a84c-27bd7075eda0","order_by":4,"name":"Eung Jin Shin","email":"","orcid":"","institution":"Soonchunhyang University College of Medicine, Soonchunhyang University Bucheon Hospital","correspondingAuthor":false,"prefix":"","firstName":"Eung","middleName":"Jin","lastName":"Shin","suffix":""}],"badges":[],"createdAt":"2026-01-01 14:53:24","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8495808/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8495808/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":100401513,"identity":"9511bd4e-25ed-494e-97ba-72608d3a7e15","added_by":"auto","created_at":"2026-01-16 11:58:57","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":732072,"visible":true,"origin":"","legend":"","description":"","filename":"IMVligation.docx","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/ee2a497ebf634250922a037c.docx"},{"id":100401978,"identity":"d5cc8807-9b1b-45ab-8434-feece0ad1b29","added_by":"auto","created_at":"2026-01-16 11:59:32","extension":"json","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":6774,"visible":true,"origin":"","legend":"","description":"","filename":"2774c64f2bff403fb164177214dd8b95.json","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/0c30625459f3891ad41ee905.json"},{"id":100401912,"identity":"4bad6877-b220-4877-8c8d-b8612e09fac8","added_by":"auto","created_at":"2026-01-16 11:59:26","extension":"xml","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":83265,"visible":true,"origin":"","legend":"","description":"","filename":"2774c64f2bff403fb164177214dd8b951enriched.xml","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/33005f67327a028eec1a41a4.xml"},{"id":100402338,"identity":"a3a1e4b7-777c-4889-a3e3-db8120f6f7c5","added_by":"auto","created_at":"2026-01-16 12:00:01","extension":"jpeg","order_by":3,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1561382,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/4cc2175dd81943feb1882b5b.jpeg"},{"id":100402487,"identity":"a2a3706b-22a7-4421-9395-3b4670bc8fbb","added_by":"auto","created_at":"2026-01-16 12:00:15","extension":"jpeg","order_by":4,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":155684,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/380e2b1a2f3b475e89b57fe1.jpeg"},{"id":100401708,"identity":"27803ead-4f5e-4a50-968f-e74d50e96f16","added_by":"auto","created_at":"2026-01-16 11:59:11","extension":"png","order_by":5,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":543110,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/2589586dc31c8588f970bd62.png"},{"id":100401485,"identity":"941cd083-2b49-4808-a800-239b4b74924f","added_by":"auto","created_at":"2026-01-16 11:58:56","extension":"png","order_by":6,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":50956,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/1498d5c7ec7acb9c5e79546d.png"},{"id":100401557,"identity":"91586d2e-6c10-4940-89ef-e471d93995c7","added_by":"auto","created_at":"2026-01-16 11:59:05","extension":"xml","order_by":7,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":83869,"visible":true,"origin":"","legend":"","description":"","filename":"2774c64f2bff403fb164177214dd8b951structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/803718d6bb568dc930e0771a.xml"},{"id":100402297,"identity":"4d901d0d-5b52-4758-939c-2fbcfee3bbc4","added_by":"auto","created_at":"2026-01-16 11:59:53","extension":"html","order_by":8,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":91995,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/9c5629900abdb5882cf5dcc8.html"},{"id":100401199,"identity":"7b694ac0-420c-47a5-bb5b-a29b57eb7b3c","added_by":"auto","created_at":"2026-01-16 11:58:45","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":153707,"visible":true,"origin":"","legend":"\u003cp\u003eDefinition of ligation of inferior mesenteric vein (IMV): 1) Laparoscopic view, A: high ligation of IMV, B: low ligation of IMV, C: high ligation of IMA. 2) Other laparoscopic view of IMV ligation.\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/da846911c6ad7af89187cf2b.jpg"},{"id":100402482,"identity":"c335f679-f6bf-42cc-b311-22caaa842660","added_by":"auto","created_at":"2026-01-16 12:00:15","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":23709,"visible":true,"origin":"","legend":"\u003cp\u003eOncologic outcome between IMV high versus low ligation groups. A) 5-years disease free survival rate (%), B) 5-years overall survival rate (%).\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/bb04eb9696cf920d5e2aeb2b.jpg"},{"id":102030373,"identity":"22f4aa07-3aa4-4cb6-b97c-87efc32288bf","added_by":"auto","created_at":"2026-02-06 10:42:55","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1059217,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8495808/v1/0ccb3de8-6914-4c57-b1bd-ae467d76de39.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"A Comparative Study of Clinical Outcomes According to the Level of Inferior Mesenteric Vein Ligation in Laparoscopic Colorectal Cancer Surgery","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSurgery remains the cornerstone of curative treatment for colorectal cancer, and laparoscopic colorectal cancer surgery has become a standard approach, providing oncologic outcomes comparable to open surgery while offering the benefits of reduced postoperative pain, faster recovery, and shorter hospital stay [\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. During laparoscopic anterior resection or low anterior resection, vascular ligation plays a critical role in achieving adequate oncologic clearance and facilitating safe mobilization of the colon. In colorectal cancer surgery, both the inferior mesenteric artery (IMA) and inferior mesenteric vein (IMV) ligation are routinely ligated during mesenteric mobilization. While the optimal level of IMA ligation has been extensively investigated, including its impact on oncologic outcomes and anastomotic perfusion, the clinical significance of the level of IMV ligation remains less well defined. Anatomically, the IMV courses in close proximity to the pancreas and splenic vessels, and its level of ligation may influence operative complexity, the extent of mesocolic mobilization, and risk of injury to adjacent structures. High ligation of the IMV at the level of the inferior border of the pancreas has been advocated to facilitate splenic flexure mobilization and to reduce mesenteric tension, potentially allowing for a tension-free colorectal anastomosis. Conversely, low ligation of the IMV near the origin of the IMA may simplify the operative procedure and reduce the risk of pancreatic or collateral vessel injury [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. In addition, preservation of venous drainage through low IMV ligation has been proposed to reduce venous congestion and bowel wall edema at the anastomotic site. Despite these theoretical considerations, available evidence comparing high and low IMV ligation is limited, and previously published studies have reported inconsistent results regarding perioperative outcomes and oncologic adequacy [\u003cspan additionalcitationids=\"CR7 CR8 CR9 CR10\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Moreover, most prior investigations have primarily focused on arterial ligation strategies, with comparatively little attention given to the clinical implications of IMV ligation level. As a result, the optimal approach to IMV management during laparoscopic colorectal cancer surgery remains controversial, and clinical guidance is lacking. Therefore, the present study aimed to compare perioperative outcomes, postoperative complications, and long-term oncologic outcomes according to the level of IMV ligation in patients undergoing laparoscopic colorectal cancer surgery. By evaluating the clinical impact of high versus low IMV ligation, this study seeks to support informed surgical decision-making regarding IMV management.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatients\u003c/h2\u003e \u003cp\u003eBetween January 2016 and August 2018, a total 223 patients who underwent laparoscopic assisted low anterior resection with double stapling technique for rectal adenocarcinoma were retrospectively identified from an institutional database. Patients with synchronous and metachronous cancer were excluded. Patient with stage IV disease were also excluded from the analysis. All clinical and pathological data were reviewed retrospectively. Preoperative evaluation included colonoscopy with biopsy and staging studies using computed tomography of the chest, abdomen, and pelvis. Positron emission tomography scans were performed selectively when clinically indicated. All patients underwent curative resection. Patients with clinically staged T3 or T4 tumors and/or node-positive disease received long-course neoadjuvant chemoradiation therapy consisting of fluorouracil-based chemotherapy and a total radiation dose of 50.4 Gy. Surgical resection was performed 6\u0026ndash;8 weeks after completion of neoadjuvant therapy. Patients were followed until December 2022 or until death, if it occurred earlier. Based on the level of IMV ligation, patients were divided into two groups: high IMV ligation (n\u0026thinsp;=\u0026thinsp;138) and low IMV ligation (n\u0026thinsp;=\u0026thinsp;58) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.). The two groups were compared with respect to demographic characteristics, perioperative outcomes, postoperative morbidity, and pathological and oncologic outcomes.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eDefinition of IMV ligation and Surgery\u003c/h3\u003e\n\u003cp\u003eAll surgical procedures were performed laparoscopically by experienced colorectal surgeons using a standardized technique. Laparoscopic anterior resection or low anterior resection with total mesorectal excision was performed according to tumor location, following established oncologic principles. The level of IMV ligation was classified base on the anatomical site of division. Low IMV ligation was defined as division of the IMV near the root of the IMA, corresponding to the level of high IMA ligation, in which the IMA was divided approximately 1-2cm from its origin. High IMV ligation was defined as division of the IMV at a more proximal level, near the inferior border of the pancreas and close to the ligament of Treitz (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.). The choice of IMV ligation level was determined by the operating surgeon based on intraoperative anatomical considerations and the extent of colonic mobilization required.\u003c/p\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eAll statistical analyses were performed using SAS software version 9.1.3 (SAS Institute Inc., Cary, NC, USA) and SPSS software version 24.0 (SPSS Inc., Chicago, IL, USA). Categorical variables were analyzed using the chi-square test or Fisher\u0026rsquo;s exact tests, as appropriate. Continuous variables were analyzed using Student\u0026rsquo;s \u003cem\u003et\u003c/em\u003e test or the Mann-Whitney \u003cem\u003eU\u003c/em\u003e test depending on data distribution. Overall survival (OS) and disease-free survival (DFS) were estimated using the Kaplan-Meier method and compared between groups using the log-rank test. To identify independent prognostic factors for DFS, univariate and multivariate analyses performed using the Cox proportional hazards regression mode. Variables with clinical relevance and/or those with a p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.10 in univariate analysis were entered into the multivariate model. Proportional hazards assumptions were assessed using log-minus-log plots and/or Schoenfeld residuals. Results are presented as hazard ratios (HRs) with 95% confidence intervals (Cis). A two-sided p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eEthics\u003c/h3\u003e\n\u003cp\u003e This study was approved by the institutional Review Board of Soonchunhyang University Bucheon Hospital (IRB No: SCHBC2025-0\u0026hellip;..). Given the retrospective study design and anonymized data collection, the requirement for informed consent was waived.\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003ePatients characteristics\u003c/h2\u003e \u003cp\u003ePatient characteristics were compared between the high IMV ligation group (n\u0026thinsp;=\u0026thinsp;138) and low IMV ligation group (n\u0026thinsp;=\u0026thinsp;85) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.). There were no significant differences between the two groups with respect to mean age, sex distribution, height, weight, body mass index (BMI), and ASA scores, or history of previous abdominal surgery. The rate of neoadjuavnt chemoradiation therapy rate was significantly higher in the high IMV ligation group than in the low IMV ligation group (23.2% vs. 10.6%, p\u0026thinsp;=\u0026thinsp;0.018). The rate of adjuvant chemotherapy did not differ significantly between the two groups (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\u003ePatient characteristics (n\u0026thinsp;=\u0026thinsp;223)\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\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHigh IMV ligation (n\u0026thinsp;=\u0026thinsp;138) (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLow IMV ligation (n\u0026thinsp;=\u0026thinsp;85) (%)\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\u003eAge(mean\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\:\\text{S}\\text{D},\\:\\left(\\text{r}\\text{a}\\text{n}\\text{g}\\text{e}\\right)\\)\u003c/span\u003e\u003c/span\u003e) (year)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e63.4\u0026thinsp;\u0026plusmn;\u0026thinsp;9.9(32\u0026ndash;85)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e63.8\u0026thinsp;\u0026plusmn;\u0026thinsp;12.6(33\u0026ndash;89)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.820\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex, n (%)\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\u003e0.634\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\u003e84(60.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e49(57.6%)\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\u003e54(39.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e36(42.4%)\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\u003eWeight(mean\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\:\\text{S}\\text{D},\\:\\left(\\text{r}\\text{a}\\text{n}\\text{g}\\text{e}\\right)\\)\u003c/span\u003e\u003c/span\u003e) (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e62.6\u0026thinsp;\u0026plusmn;\u0026thinsp;11.0\u003c/p\u003e \u003cp\u003e(38.0-100.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e62.0\u0026thinsp;\u0026plusmn;\u0026thinsp;11.0\u003c/p\u003e \u003cp\u003e(32.0-86.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.638\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHeight(mean\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\:\\text{S}\\text{D},\\:\\left(\\text{r}\\text{a}\\text{n}\\text{g}\\text{e}\\right)\\)\u003c/span\u003e\u003c/span\u003e) (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e161.3\u0026thinsp;\u0026plusmn;\u0026thinsp;8.4\u003c/p\u003e \u003cp\u003e(136.5-178.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e160.4\u0026thinsp;\u0026plusmn;\u0026thinsp;9.3\u003c/p\u003e \u003cp\u003e(141.1-181.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.160\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI(mean\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\:\\text{S}\\text{D},\\:\\:\\left(\\text{r}\\text{a}\\text{n}\\text{g}\\text{e}\\right)\\)\u003c/span\u003e\u003c/span\u003e) (Kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23.9\u0026thinsp;\u0026plusmn;\u0026thinsp;3.2(16.8\u0026ndash;36.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24.0\u0026thinsp;\u0026plusmn;\u0026thinsp;3.3(14.6\u0026ndash;33.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.799\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eASA score, n (%)\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\u003e0.205\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e70(50.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e36(42.4%)\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\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e57(41.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e45(52.9%)\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\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11(8.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4(4.7%)\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\u003ePrevious abdomen surgery\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\u003e0.385\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10(7.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9(10.6%)\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\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e128(92.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e76(89.4%)\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\u003eNeoadjuvant chemoradiation therapy\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\u003e0.018\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e32(23.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9(10.6%)\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\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e106(76.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e76(89.4%)\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\u003eAdjuvant chemotherapy\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\u003e0.112\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e58(42.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e45(52.9%)\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\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e80(58.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40(47.1%)\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\n\u003ch3\u003ePathologic results\u003c/h3\u003e\n\u003cp\u003e Pathologic staging was performed according to the American Joint Committee on Cancer (AJCC) 8th edition. There was no significant difference in overall TNM stage distribution between the two groups (p\u0026thinsp;=\u0026thinsp;0.585). Similarly, pT stage and pN stage distributions were comparable. Histological grades of differentiation, lymphovascular invasion rate, perineural invasion rate, proximal resection margin, distal resection margin, and tumor size did not differ significantly between the high and low IMV ligation groups. The mean number of harvested lymph nodes was also comparable between the two groups (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePostoperative pathologic outcomes (n\u0026thinsp;=\u0026thinsp;223)\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=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" 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\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHigh IMV ligation (n\u0026thinsp;=\u0026thinsp;138) (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLow IMV ligation (n\u0026thinsp;=\u0026thinsp;85) (%)\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\u003epTNM stage, no. (%)\u003c/p\u003e \u003cp\u003eCR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4(2.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2(2.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.585\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=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e35(25.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e25(29.4%)\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\u003eIIa\u003c/p\u003e \u003cp\u003eIIb\u003c/p\u003e \u003cp\u003eIIIa\u003c/p\u003e \u003cp\u003eIIIb\u003c/p\u003e \u003cp\u003eIIIc\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e48(34.8%)\u003c/p\u003e \u003cp\u003e2(1.4%)\u003c/p\u003e \u003cp\u003e8(5.8%)\u003c/p\u003e \u003cp\u003e35(25.4%)\u003c/p\u003e \u003cp\u003e6(4.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e22(25.9%)\u003c/p\u003e \u003cp\u003e2(2.4%)\u003c/p\u003e \u003cp\u003e6(7.1%)\u003c/p\u003e \u003cp\u003e19(22.4%)\u003c/p\u003e \u003cp\u003e9(10.6%)\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\u003epT/ypT stage, no. (%)\u003c/p\u003e \u003cp\u003eCR/0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4(2.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2(2.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.489\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e27(19.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e16(18.8%)\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\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e21(15.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e15(17.6%)\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\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e80(58.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e46(54.1%)\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\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e6(4.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6(7.1%)\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\u003epN/ypN stage, no. (%)\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\u003e0.211\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0\u003c/p\u003e \u003cp\u003e1a\u003c/p\u003e \u003cp\u003e1b\u003c/p\u003e \u003cp\u003e1c\u003c/p\u003e \u003cp\u003e2a\u003c/p\u003e \u003cp\u003e2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e89(64.5%)\u003c/p\u003e \u003cp\u003e13(9.4%)\u003c/p\u003e \u003cp\u003e7(5.1%)\u003c/p\u003e \u003cp\u003e3(2.2%)\u003c/p\u003e \u003cp\u003e15(10.9%)\u003c/p\u003e \u003cp\u003e11(8.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e50(58.8%)\u003c/p\u003e \u003cp\u003e9(10.6%)\u003c/p\u003e \u003cp\u003e14(16.5%)\u003c/p\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e4(4.7%)\u003c/p\u003e \u003cp\u003e8(9.4%)\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\u003eGrade of differentiation, no. (%)\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\u003e0.709\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWell\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e13(9.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e11(12.9%)\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\u003eModerate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e117(84.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e69(81.2%)\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\u003ePoor\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8(5.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5(5.9%)\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\u003eMucinous\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHarvested no. of lymph nodes, (mean\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\:\\)\u003c/span\u003e\u003c/span\u003eSD, range), (No)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e17.0\u0026thinsp;\u0026plusmn;\u0026thinsp;9.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e16.7\u0026thinsp;\u0026plusmn;\u0026thinsp;7.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.065\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLymphovascular invasion\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\u003e0.856\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e109(79.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e68(80.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003cp\u003ePerineural invasion\u003c/p\u003e \u003cp\u003eNo\u003c/p\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e29(21.0%)\u003c/p\u003e \u003cp\u003e83(60.1%)\u003c/p\u003e \u003cp\u003e55(39.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e17(20.0%)\u003c/p\u003e \u003cp\u003e45(52.9%)\u003c/p\u003e \u003cp\u003e40(47.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.291\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePRM, (mean\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\:\\)\u003c/span\u003e\u003c/span\u003eSD, range), (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e9.7\u0026thinsp;\u0026plusmn;\u0026thinsp;7.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e9.8\u0026thinsp;\u0026plusmn;\u0026thinsp;5.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.711\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDRM, (mean\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\pm\\:\\:\\)\u003c/span\u003e\u003c/span\u003eSD, range), (cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4.3\u0026thinsp;\u0026plusmn;\u0026thinsp;3.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3.9\u0026thinsp;\u0026plusmn;\u0026thinsp;1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.121\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMass size\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e3.8\u0026thinsp;\u0026plusmn;\u0026thinsp;2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3.6\u0026thinsp;\u0026plusmn;\u0026thinsp;1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.108\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003ePRM: proximal resection margin, DRM: Distal resection margin\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003ePeri-operative outcomes\u003c/h3\u003e\n\u003cp\u003eThe mean operation time was significantly longer in the high IMV ligation group than in the low IMV ligation group (198.6\u0026thinsp;\u0026plusmn;\u0026thinsp;55.5 minutes vs. 180.8\u0026thinsp;\u0026plusmn;\u0026thinsp;67.7, p\u0026thinsp;=\u0026thinsp;0.019). Mean intraoperative blood loss did not differ significantly between the two group (100.5 ml vs. 96.2 ml, p\u0026thinsp;=\u0026thinsp;0.429). The mean length of hospital stay was 9.3 days in high IMV ligation group and 9.1 days in low IMV ligation group, with no significant difference (p\u0026thinsp;=\u0026thinsp;0.590). The overall postoperative morbidity comparable between the two groups (12.3% vs. 12.0%, p\u0026thinsp;=\u0026thinsp;0.902). Anastomotic leakage occurred in 2.2% (n\u0026thinsp;=\u0026thinsp;3) of patients in the high IMV ligation group and 1.2% (n\u0026thinsp;=\u0026thinsp;1) of patients in the low IMV ligation group, with no significant difference (p\u0026thinsp;=\u0026thinsp;0.602). Rates of intestinal obstruction or ileus were 5.1% (n\u0026thinsp;=\u0026thinsp;7) in the high ligation group and 1.2% (n\u0026thinsp;=\u0026thinsp;1) in the low ligation group. There was no significant difference in postoperative mortality between the two groups (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePeri-postoperative outcomes at High IMV versus Low IMV ligation groups (n\u0026thinsp;=\u0026thinsp;223).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHigh IMV ligation (n\u0026thinsp;=\u0026thinsp;138) (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLow IMV ligation (n\u0026thinsp;=\u0026thinsp;85) (%)\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\u003eOperation time (min)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e198.6\u0026thinsp;\u0026plusmn;\u0026thinsp;55.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e180.8\u0026thinsp;\u0026plusmn;\u0026thinsp;67.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.019\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood loss (ml)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100.5\u0026thinsp;\u0026plusmn;\u0026thinsp;114.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e96.2\u0026thinsp;\u0026plusmn;\u0026thinsp;148.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.429\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLength of hospital stay (day)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.3\u0026thinsp;\u0026plusmn;\u0026thinsp;2.6(7\u0026ndash;24)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.9(7\u0026ndash;27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.590\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime to sips of water (day)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.4(3\u0026ndash;6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.4\u0026thinsp;\u0026plusmn;\u0026thinsp;0.9(3\u0026ndash;10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTime to liquid diet (day)\u003c/p\u003e \u003cp\u003eTime to soft diet (day)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2(3\u0026ndash;14)\u003c/p\u003e \u003cp\u003e6.3\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2(4\u0026ndash;15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.3(4\u0026ndash;12)\u003c/p\u003e \u003cp\u003e6.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.3(4\u0026ndash;13)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.557\u003c/p\u003e \u003cp\u003e0.643\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal Morbidity (n; %)\u003c/p\u003e \u003cp\u003eUrinary disfunction\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17(12.3%)\u003c/p\u003e \u003cp\u003e2(1.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10(12.0%)\u003c/p\u003e \u003cp\u003e2(2.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.902\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePulmonary disease\u003c/p\u003e \u003cp\u003eIleus/intestinal obstruction\u003c/p\u003e \u003cp\u003eLate intestinal obstruction\u003c/p\u003e \u003cp\u003eWound infection\u003c/p\u003e \u003cp\u003eAnastomosis site leakage\u003c/p\u003e \u003cp\u003eMajor leakage\u003c/p\u003e \u003cp\u003eMinor leakage\u003c/p\u003e \u003cp\u003eDelayed leakage\u003c/p\u003e \u003cp\u003eAnal stenosis\u003c/p\u003e \u003cp\u003eBleeding\u003c/p\u003e \u003cp\u003eIschemia\u003c/p\u003e \u003cp\u003eSepsis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2(1.4%)\u003c/p\u003e \u003cp\u003e7(5.1%)\u003c/p\u003e \u003cp\u003e1(0.7%)\u003c/p\u003e \u003cp\u003e1(0.7%)\u003c/p\u003e \u003cp\u003e3 (0.0%)\u003c/p\u003e \u003cp\u003e1(0.7%)\u003c/p\u003e \u003cp\u003e1(0.7%)\u003c/p\u003e \u003cp\u003e1(0.7%)\u003c/p\u003e \u003cp\u003e1(0.7%)\u003c/p\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e0(0/0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2(2.4%)\u003c/p\u003e \u003cp\u003e1(1.2%)\u003c/p\u003e \u003cp\u003e1(1.2%)\u003c/p\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e1(1.2%)\u003c/p\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e1(1.2%)\u003c/p\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e1(1.2%)\u003c/p\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e1(1.2%)\u003c/p\u003e \u003cp\u003e1(1.2%)\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\u003eTotal Mortality\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1(1.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eOncologic outcomes and Recurrent patterns after surgery\u003c/h2\u003e \u003cp\u003eThe mean follow-up duration was 49.4 months. There was no significant differences between the two groups in 5-year overall survival, disease-free survival, local recurrence, or distant recurrence rate. The 5-year overall survival rate was 92.7% in high IMV ligation group and 88.5% in low IMV ligation group (p\u0026thinsp;=\u0026thinsp;0.562). The 5-year disease free survival rate was 88.4% in high IMV ligation group and 88.5% in low IMV ligation group (p\u0026thinsp;=\u0026thinsp;0.743) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.). The overall recurrence rate was 13.0% in high IMV ligation group and 10.6% in low IMV ligation group (p\u0026thinsp;=\u0026thinsp;0.601). Local recurrence occurred in 0.7% of patients in the high IMV ligation group and 2.4% in the low IMV ligation group. Distant recurrence rates were 12.3% and 8.2%, respectively. Recurrent patterns did not differ significantly different between the two groups (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e.).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eRecurrence pattern of IMV high versus low ligation groups (n\u0026thinsp;=\u0026thinsp;223).\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=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHigh IMV ligation (n\u0026thinsp;=\u0026thinsp;138) (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLow IMV ligation (n\u0026thinsp;=\u0026thinsp;85) (%)\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\u003eTotal Number of Recurrence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e18(13.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e9(10.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.601\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSystemic recurrence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e17(12.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7(8.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLung\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7(5.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4(4.7%)\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\u003eLiver\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4(2.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3(3.5%)\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\u003eParaaortic node\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4(2.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBone\u003c/p\u003e \u003cp\u003ePeritoneum\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e2(1.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLocal recurrence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1(0.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e2(2.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNS\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePelvic side wall\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1(1.2%)\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\u003ePerineum\u003c/p\u003e \u003cp\u003eRectal fossa\u003c/p\u003e \u003cp\u003eAnastomosis site\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e1(0.7%)\u003c/p\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e0(0.0%)\u003c/p\u003e \u003cp\u003e1(1.2%)\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 \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eUnivariate and multivariate analysis of prognostic factors for 5-year disease free survival\u003c/h2\u003e \u003cp\u003eUnivariate and multivariate Cox proportional hazards regression analyses were performed to identify prognostic factors for 5-year disease free survival. In univariate analysis, sex, age, BMI, tumor size, N stage, histological grade, perineural invasion, and neoadjuvant chemoradiation therapy were not significantly associated with disease free survival. T stage, lymphovascular invasion, and adjuvant chemotherapy were significantly associated with disease-free survival in univariate analysis. In multivariate analysis, T stage remained an independent prognostic factor. The level of IMV ligation was not associated with disease-free survival in either univariate (odds ratio 0.87; 95% confidence interval 0.39\u0026ndash;1.96; p\u0026thinsp;=\u0026thinsp;0.744) or multivariate analysis (odds ratio 0.88; 95% confidence interval 0.39\u0026ndash;1.99; p\u0026thinsp;=\u0026thinsp;0.764) (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e.).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eUnivariate and multivariate Cox proportional hazards regression analyses of prognostic factor for disease free survival\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\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003eUnivariate analysis\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c7\" namest=\"c5\"\u003e \u003cp\u003eMultivariate analysis\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFactors\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge, years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.04\u0026ndash;2.49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.272\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 \u003cp\u003e(\u0026lt;\u0026thinsp;70 vs. \u0026ge;70)\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 \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 \u003cp\u003eSex\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.38\u0026ndash;1.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.665\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 \u003cp\u003e(Male vs. Female)\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 \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 \u003cp\u003eBMI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.62\u0026ndash;2.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.447\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 \u003cp\u003e(\u0026lt;\u0026thinsp;25 vs. \u0026ge;25)\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 \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 \u003cp\u003eTumor size, cm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.56\u0026ndash;2.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.584\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 \u003cp\u003e(\u0026lt;\u0026thinsp;5 vs. \u0026ge;5)\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 \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 \u003cp\u003eT stage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.63\u0026ndash;18.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.06\u0026ndash;0.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.027\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e(T1-2 vs. T3-4)\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 \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 \u003cp\u003eN stage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.74\u0026ndash;3.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.239\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 \u003cp\u003e(N0 vs. N1-2)\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 \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 \u003cp\u003eHistological grade\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.85\u0026ndash;9.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.091\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 \u003cp\u003e(Well-mod. vs. others)\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 \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 \u003cp\u003eLymphovascular invasion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.01\u0026ndash;5.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.046\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.26\u0026ndash;1.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.259\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e(present vs. absent)\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 \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 \u003cp\u003ePerineural invasion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.89\u0026ndash;4.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.099\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 \u003cp\u003e(present vs. absent)\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 \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 \u003cp\u003eNeoadjuvant chemoradiation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.67\u0026ndash;3.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.285\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 \u003cp\u003e(Yes vs. No)\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 \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 \u003cp\u003eAdjuvant chemotherapy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.10\u0026ndash;6.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.030\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.46\u0026ndash;3.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.609\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e(Yes vs. No)\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 \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 \u003cp\u003eInferior mesenteric vein\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.39\u0026ndash;1.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.744\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.39\u0026ndash;1.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.764\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e(high ligation vs. low ligation)\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 \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 \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn the present study, we evaluated the clinical impact of the level of IMV ligation in laparoscopic colorectal cancer surgery. Our results demonstrated that the level of IMV ligation-whether high or low-was not associated with significant differences in postoperative morbidity or long-term oncologic outcomes. These findings suggest that both high and low IMV ligation strategies can be safely applied without compromising short term surgical safety or oncologic adequacy. High ligation of the IMV has traditionally been advocated to facilitate splenic flexure mobilization and to achieve a tension-free anastomosis, particularly in patients requiring low pelvis anastomosis. In the present study, high IMV ligation was associated with a longer operative time but was not linked to increased blood loss, postoperative complications, or anastomotic leakage. These results indicate that high IMV ligation can be performed safely in the laparoscopic setting when adequate surgical expertise is available, despite its potential technical complexity.\u003c/p\u003e \u003cp\u003eConversely, low ligation of the IMV has been proposed to preserve venous drainage of the remnant colon, thereby reducing venous congestion and bowel wall edema at the anastomotic site. Another potential advantages of low IMV ligation is avoidance of injury to adjacent collateral vessels [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Anatomical studies using computed tomography angiography have reported that the Arc of Riolan may course along the inferior border of the pancreas and cross anterior to the IMV in approximately 10\u0026ndash;40% of patients [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. These vessels may be encountered during skeletonization of the IMV for high ligation, posing a potential risk of inadvertent injury. Previous studies have emphasized the importance of careful dissection to avoid collateral vessels damage during IMV ligation [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Although low IMV ligation did not significantly reduce the rate of anastomotic leakage in the present study, a trend toward fewer anastomosis related complications was observed. This finding supports the theoretical advantage of preserving venous outflow and suggests that low IMV ligation may be considered in selected patients who are at higher risk for anastomotic complications.\u003c/p\u003e \u003cp\u003eFrom an oncologic standpoint, both IMV ligation strategies achieved comparable lymph node yields and pathological outcomes. In addition, no significant differences were observed in disease-free or overall survival between the two group. These findings suggest that, unlike arterial ligation, the level of IMV ligation may play a limited role in determining oncologic radicality, provided that standard oncologic principles including adequate mesocolic excision and lymphadenectomy are followed. Our results therefore support an individualized approach to IMV ligation based on patient anatomy, tumor location, and the extent colonic mobilization required, rather than strict adherence to a single standardized technique.\u003c/p\u003e \u003cp\u003eSeveral limitations of this study should be acknowledged. First, the retrospective design introduces the possibility of selection bias, as the choice of IMV ligation level was determined by surgeon preference rather than randomization. Second, although the sample size was relatively large compared with previous reports, the study may still be underpowered to detect small differences in rare complications, such as anastomotic leakage. Third, this study is single institution study which may limit the generalizability of the findings. Finally, although long-term oncologic outcomes were evaluated, residual confounding factors inherent to retrospective analyses cannot be completely excluded. Future prospective, multi-institutional studies are warranted to further clarify the optimal strategy for IMV ligation in laparoscopic colorectal cancer surgery.\u003c/p\u003e \u003cp\u003eDespite these limitations, this study provides clinically relevant evidence regarding IMV ligation strategy in laparoscopic colorectal cancer surgery. The findings suggest that both high and low IMV ligation can be safely performed with comparable short term and oncologic outcomes. Therefore, the choice of IMV ligation level may be tailored according to individual patient anatomy, tumor location, and the extent of colonic mobilization required.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn laparoscopic colorectal cancer surgery, the level of IMV ligation was not associated with significant differences in short term postoperative outcomes or oncologic adequacy. Both high and low IMV ligation strategies achieved comparable surgical safety and pathological results when standard oncologic principles were followed. These findings suggest that routine high ligation of the IMV may not be mandatory in all cases. Instead, the IMV ligation level can be individualized according to patient anatomy, tumor location, and the extent of colonic mobilization required to achieve a safe, tension-free anastomosis.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eDae Ro Lim worte the main manuscript text. Dae Ro Lim, Nahyeon Park and Go Won Park prepared a table and a figure. Dae Ro Lim, Jung Kul Kuk and Eung Jin Shin collected and analyzed data.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e \u003cp\u003eAll authors declare no conflict of interest in this work. Informed consent was not required due to the retrospective design. This work was supported by the Soonchunhyang University Research Fund.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eFleshman J, Sargent DJ, Green E, Anvari M, Stryker SJ, Beart RW Jr, et al. Laparoscopic colectomy for cancer is not inferior to open surgery based on 5-year data from the COST Study Group trial. Ann Surg 2007;246:655\u0026ndash;62.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJayne DG, Thorpe HC, Copeland J, Quirke P, Brown JM, Guillou PJ. Five-year follow-up of the Medical Research Council CLASICC trial of laparoscopically assisted versus open surgery for colorectal cancer. Br J Surg 2010;97:1638\u0026ndash;45.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCOLOR Study Group. COLOR: a randomized clinical trial comparing laparoscopic and open resection for colon cancer. Dig Surg 2000;17:617\u0026ndash;22.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eA C Lowry, C L Simmang, P Boulos, K C Farmer, P J Finan, M Killinhback, et al. Consensus statement of definitions for anorectal physiology and rectal cancer: report of the tripartite consensus conference on definitions for anorectal physiology and rectal cancer, Washington, D.C., May 1, 1999. Dis Colon Rectum. 2001;44:915-9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCirocchi R, Trastulli S, Farinella E, Desiderio J, Vettoretto N, Paris A, et al. High tie versus low tie of the inferior mesenteric artery in colorectal cancer: a RCT is needed. Surg Oncol. 2012;21:111\u0026ndash;23.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLange MM, Buunen M, van de Velde CJ, Lange JF. Level of arterial ligation in rectal cancer surgery: low tie preferred over high tie: a review. Dis Colon Rectum. 2008;51:1139\u0026ndash;45.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZeng J, Su G. High ligation of the inferior mesenteric artery during sigmoid colon and rectal cancer surgery increase the risk of anastomotic leakage: a meta-analysis. World J Surg Oncol. 2018;16:157.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKim K, An S, Kim MH, Jung JH, Kim Y. High versus low ligation of the inferior mesenteric artery in colorectal cancer surgery: a systematic review and meta-analysis. Medicina(Kaunas). 2022;58:1143.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGirard E, Trilling B, Rabattu PY, Taton N, Robert Y, Chaffanjon P, et al. Level of inferior mesenteric artery ligation in low rectal cancer surgery: high tie preferred over low tie. Tech coloproctol. 2019;23:267\u0026ndash;71.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYang Y, Wang G, He J, Zhang J, Xi J, Wang F. High tie versus low tie of the inferior mesenteric artery in colorectal cancer: a meta-analysis. Int J Surg. 2018;52:20\u0026ndash;24.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGarcia-Granero A, Pellino G, Frasson M, Primo Romaguera V, Fletcher-Sanfeliu D, Blasco Serra A, et al. Possible effects of height of ligation of the inferior mesenteric vein on venous return of the colorectal anastomosis: the venous trunk theory. Tech Coloproctol. 2019;23:799\u0026ndash;800.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eS Bonnet, A Berger, N Hentati, B Abid, J-M Chevallier, P Wind, et al. High tie versus low tie vascular ligation of the inferior mesenteric artery in colorectal cancer surgery: impact on the gain in colon length and implications on the feasibility of anastomoses. Dis Colon Rectum. 2012;55:515\u0026ndash;21.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAl-Asari SF, Lim D, Min BS, Kim NK. The relation between inferior mesenteric vein ligation and collateral vessels to splenic flexure: anatomical landmarks, technical precautions and clinical significance. Yonsei Med J. 2013;54:1484\u0026ndash;90.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Colorectal cancer, Inferior mesenteric vein, Laparoscopic surgery","lastPublishedDoi":"10.21203/rs.3.rs-8495808/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8495808/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePropose\u003c/strong\u003e: In colorectal cancer surgery, both the inferior mesenteric artery (IMA) and inferior mesenteric vein (IMV) are routinely ligated. While the optimal level of IMV has been extensively studied, evidence regarding the appropriate level of IMV ligation remains limited. This study aimed to evaluate clinical and oncologic outcomes according to the level of IMV ligation in laparoscopic colorectal cancer surgery.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterials and Methods:\u003c/strong\u003e Between January 2016 and August 2018, a total 223 patients who underwentlaparoscopic curative resection for colorectal cancer were retrospectively identified from an institutional database. Patients were divided into two groups according to the level of IMV ligation: high ligation (n=138) vs. low ligation (n=85). Clinical characteristics, perioperative complications, and long-term oncologic outcomes were compared between the two groups.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eWith a median follow up of 49.4 months, the overall postoperative complication rate did not differ significantly between the high and low IMV ligation groups (12.3% vs. 12.0%, p=0.902). The rate of major complications, including anastomotic leakage, ischemia, and stenosis, was also comparable (2.2% vs. 1.2%, p=0.602). The mean length of hospital stay was similar between the two groups (9.3 vs. 9.1 days, P=0.590). The 5-years disease free survivalrate were 88.4% in the high ligation group and 88.5% in the low ligation group (p = 0.743), while the 5-years overall survival ratewere 92.7% and 88.5%, respectively (p = 0.562).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e Based on present data, the level of IMV ligation – whether high or low – was not associated with significant differences in short-term postoperative outcomes or long-term oncologic results in laparoscopic anterior and low anterior resection for colorectal cancer.\u003c/p\u003e","manuscriptTitle":"A Comparative Study of Clinical Outcomes According to the Level of Inferior Mesenteric Vein Ligation in Laparoscopic Colorectal Cancer Surgery","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-16 09:14:48","doi":"10.21203/rs.3.rs-8495808/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"281b188c-fc77-48f4-ab53-61d089c377b3","owner":[],"postedDate":"January 16th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-02-06T10:40:50+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-16 09:14:48","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8495808","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8495808","identity":"rs-8495808","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}