Genitourinary Function And Defecation After Colorectal Cancer Surgery With Low-and High-Ligation Of The Inferior Mesenteric Artery:A Meta-Analysis

Objective:Whether low ligation of the inferior mesenteric artery reduces postoperative impairment of genitourinary function and defecation in patients with colorectal cancer without affecting surgical and oncologic outcomes.Methods:EMBASE,Pub Med,Web of Science,and the Cochrane Library were systematically searched to retrieve studies describing sigmoid colon and rectal cancer surgery in order to compare outcomes following low ligation and high ligation(search last updated in December,2020).A total of 14 articles,including 4750 patients,were analyzed using Review Manager 5.3 software and STATA 16.0 software.Dichotomous results are expressed as odds ratios(ORs)with 95%confidence intervals(CIs)and continuous outcomes are expressed as mean differences(MDs)with 95%CIs.I~2 statistics andχ~2 test(Cochran Q test)were used to assess the heterogeneity between studies.If P<0.10 or I~2>50%,the analysis was performed using the random effects model;otherwise the fixed effects model was used.In addition,subgroup and sensitivity analyses were performed to determine the source of heterogeneity.For meta-analyses that included more than 10original studies,publication bias was assessed.Results:Low ligation resulted in a significantly lower incidence of nocturnal bowel movement(OR=0.73,95%CI:0.55 to 0.97,P=0.03)and anastomotic stenosis(OR=0.31,95%CI:0.16 to 0.62,P=0.0009)compared with high ligation.The risk of postoperative urinary dysfunction,however,did not differ significantly between the two techniques.Our meta-analysis also indicated that there were no significant differences between low ligation and high ligation in terms of total number of lymph nodes harvested,operative time,intraoperative bleeding,postoperative complication rate,tumor recurrence rate,mortality,anastomotic leak incidence,5-year overall survival rate and disease-free survival rate.Conclusion:As low ligation might lead to better bowel function and a reduced rate of anastomotic stenosis after colorectal cancer surgeries,and does not affect operative time,intraoperative bleeding and oncologic outcomes.We therefore suggest that low ligation may be preferred over high ligation to some extent.