BackgroundThe aim of this study was to conduct a meta-analysis comparing the oncological, intraoperative and safety outcomes in sigmoid and rectal cancer surgery with and without preservation of the left colic artery (LCA). MethodWe searched Medline, Embase, China National Knowledge Infrastructure (CNKI), and PubMed databases for relevant articles published between 1962 and 2017. Randomized and non-randomized clinical trials were identified and included in the study. End-points evaluated included 5-year mortality, number of patients with retrieved positive metastatic lymph nodes (LN) at the root of inferior mesenteric artery (IMA), number of retrieved LNs, morbidity, mortality, recurrence, bowel obstruction, intraoperative blood loss, anastomotic leakage, operation time, surgical site infection and postoperative bleed. Meta-analysis was conducted using RevMan 5.3 software. The odds ratio (OR) with 95% confidence intervals (CI) was used to analyze dichotomous data. ResultsSeventeen studies including 6247 patients were identified for the meta-analysis. Meta-analysis revealed that preserving the LCA was associated with reduced anastomotic leakage rate (OR, 0.78; 95% CI, 0.62–0.98; P = 0.03). There were no significant differences between the two groups with respect to the 5-year mortality, number of retrieved LNs, number of patients with retrieved positive metastatic LNs at the root of IMA, morbidity, mortality, recurrence, bowel obstruction, intraoperative blood loss, operation time, surgical site infection and postoperative bleed. ConclusionIn comparison with ligating the left colic artery, preserving the left colic artery seems to achieve comparable success with acceptable safety outcomes and we suggest to preserve the LCA in the sigmoid and rectal cancer surgeries. However, more multicenter randomized controlled trials are required to further evaluate the efficacy and safety of preserving the left colic artery in surgeries.