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

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.