Diverting stoma with anterior resection for rectal cancer: does it reduce overall anastomotic leakage and leaks requiring laparotomy?

Anastomotic leakage (AL) after resection for rectal carcinoma accelerates morbidity and mortality rates, extends hospital stay, and increases treatment costs, particularly when requiring laparotomy. The role of a protective diverting stoma (DS) in avoiding leakage has repeatedly been discussed, but prospective randomized studies on this subject are rare and their results contradictory. The MEDLINE database was searched for studies of AL requiring laparotomy and of the associated rate of protective DSs in initial anterior resection (AR) to review these studies systematically. The collected data were used to determine the average rate of AL requiring laparotomy after rectal cancer surgery in the DS group compared with that in the non-DS group. A total of 930 abstracts were retrieved from MEDLINE; 15 articles on AR and 22 on low/ultralow AR (LAR) were included in the review and analysis. The overall rate of AL requiring laparotomy was 6.57% (813/12, 376) in the AR studies and 4.13% (157/3, 802) in the LAR studies. In the AR studies, the pooled AL rate in the DS group was higher than that in the non-DS group (12.30% vs. 9.16%, P < 0.001). However, the pooled rate of AL requiring laparotomy in the DS group was lower than that in the non-DS group (3.69% vs. 7.42%, P < 0.001). In the LAR studies, the pooled AL rate in the DS group was lower than that in the non-DS group (7.74% vs. 9.64%, P = 0.045). The pooled rate of AL requiring laparotomy in the DS group was also lower than that in the non-DS group (2.67% vs. 5.21%, P < 0.001). By contrast, the pooled rate of definitive stomas and mortality caused by AL did not have any statistical difference between the DS and non-DS groups in both AR studies (definitive stomas: 0% vs. 0.65%; mortality: 0.95% vs. 1.19%) and LAR studies (definitive stomas: 1.03% vs. 1.01%; mortality: 0.35% vs. 0.36%). Protective DSs significantly decrease the rate of AL in LAR. AL requiring surgical correction was significantly reduced in the DS group in both AR and LAR studies. Protective DSs did not affect the definitive stomas and mortality rate; this lack of an effect warrants further high-quality clinical trials.