Potential short-term outcome advantage of low vs. high ligation of inferior mesenteric artery for sigmoid and rectal cancer: propensity score matching analysis

Background: Whether to ligate the inferior mesenteric artery at its root during anterior resection for sigmoid colon or rectal cancer is still under debate. This study compared the surgical outcomes, postoperative recovery, and anastomotic leakage between high and low ligation of the inferior mesenteric artery through a subgroup analysis. Methods: This was a retrospective analysis of prospectively collected data. All patients who underwent colorectal resection for rectosigmoid cancer between December 2016 and December 2019 were enrolled. According to the surgical ligation level of the inferior mesenteric artery, the patients were categorized into either the high or low ligation group. The investigated population was matched using the propensity score method. Results: Overall, 894 patients with sigmoid or rectal cancer underwent elective anterior resection with high (577 patients) or low (317 patients) ligation of the inferior mesenteric artery. After the propensity score matching, 245 patients in each group were compared. High ligation of the inferior mesenteric artery was associated with higher incidence of anastomotic leakage (14.9% vs. 5.6%, P = 0.041) for mid- to low-rectum tumors and a higher incidence of complications (8.6% vs. 3.3%, P = 0.013) of grades 1–2 according to the Clavien–Dindo classification system. Conclusion: Compared with high ligation, low ligation of the inferior mesenteric artery resulted in lower likelihood of morbidity and mortality in rectal and sigmoid cancers. Moreover, low ligation was less likely to result in anastomosis leakage in mid- to low-rectal cancers.