Does the level of inferior mesenteric artery ligation affect outcomes in rectal cancer: a meta-analysis

The optimal level of inferior mesenteric artery ligation during rectal cancer surgery remains uncertain. High ligation may improve vascular length and apical nodal clearance, whereas low ligation preserves the left colic artery and may support colonic perfusion.

PubMed, Embase, Cochrane CENTRAL, and Web of Science were searched for comparative studies published from January 01, 2020 through March 31, 2026. Randomized and nonrandomized studies involving adults undergoing curative rectal cancer resection were eligible. Two reviewers independently selected studies and extracted data. Risk of bias was assessed according to study design. Random-effects models generated odds ratios for dichotomous outcomes and mean differences for continuous outcomes, each with 95% confidence intervals.

Seven studies involving 1687 patients were included. Operating time did not differ between low and high ligation (mean difference, 0.23 min; 95% CI -7.66 to 8.11). Anastomotic leakage remained comparable (odds ratio, 0.67; 95% CI 0.41-1.08; I²=0%). Hospital stay showed no difference (mean difference, -0.43 days; 95% CI -1.74 to 0.88; I²=50%). Low ligation was associated with higher urinary-retention odds (odds ratio, 2.30; 95% CI 1.56-3.40; I²=0%). Harvested lymph-node yield remained comparable (mean difference, -0.70 nodes; 95% CI -1.99 to 0.60; I²=82%). Overall complications showed no significant difference (odds ratio, 0.69; 95% CI 0.37-1.31; I²=78%).

Most short-term outcomes were comparable between ligation strategies. The urinary-retention finding favored high ligation but arose from only 3 studies and remained vulnerable to clinical confounding. Individualized operative planning should prioritize oncological adequacy, perfusion, anastomotic tension, and autonomic nerve preservation.