Postoperative morbidity and mortality after anterior resection with preventive diverting loop ileostomy versus loop colostomy for rectal cancer: A updated systematic review and meta-analysis.

The purpose of this meta-analysis was to evaluate the perioperative morbidity after anterior resection with diverting loop ileostomy (LI) versus colostomy (LC) and its reversal for rectal cancer. The studies on the application of loop ileostomy versus loop colostomy in anterior resection published from January 2000 to January 2020 were searched in the databases of Pubmed, Embase, Cochrane library, and Clinical trials. All randomized controlled trials (RCTs) and cohort studies were included according to inclusion criteria. Eight studies (2 RCTs and 6 cohort studies) totaling 1451 patients (821 LI and 630 LC) were included in the meta-analysis. The morbidity related to stoma formation and closure did not demonstrate significant differences. Significantly more LCs were complicated by stoma prolapse & retraction (OR:0.26,95%CI:0.11-0.60,P = 0.001), parastomal hernia (OR = 0.52,95%CI:0.30-0.88, P = 0.01), surgical site infection (SSI) (OR = 0.24,95%CI:0.11-0.49,P < 0.0001) and incisional hernias (OR = 0.39,95%CI:0.19-0.83,P = 0.01) than by LIs. Patients with LI demonstrated significantly more complications related to the stoma, such as dehydration (OR = 0.52,95%CI:0.30-0.88, P = 0.01) and ileus (OR = 2.23,95%CI:1.12-4.43, P = 0.02) than patients with LC. While after the subgroup analysis of different publication years, LI could reduce the risk of the morbidity after stoma formation in previous years group (P = 0.04) with a lower heterogeneity (I = 37%); LC could reduce the incidence of parastomal dermatitis in recent years group (P < 0.0001) without heterogeneity in each subgroup (I = 0%). Cumulative meta-analysis detected significant turning points in dehydration, SSI, and ileus. This meta-analysis recommends diverting LI in the anterior resection for rectal cancer, but there is a risk of dehydration, irritant dermatitis, and ileus.