Extralevator abdominoperineal excision versus abdominoperineal excision for low rectal cancer: a meta-analysis

BACKGROUND: Extralevator abdominoperineal excision (ELAPE) has become a popular procedure for low rectal cancer as compared with abdominoperineal excision (APE). No definitive answer has been achieved whether one is superior to the other. This study aimed to evaluate the safety and efficacy of ELAPE for low rectal cancer with meta-analysis. METHODS: The Web of Science, Cochrane Library, Embase, and PubMed databases before September 2019 were comprehensively searched to retrieve comparative trials of ELAPE and APE for low rectal cancer. Pooled analyses of the perioperative variables, surgical complications, and oncological variables were performed. Odds ratio (OR) and mean differences (MD) from each trial were pooled using random or fixed effects model depending on the heterogeneity of the included studies. A subgroup analysis or a sensitivity analysis was conducted to explore the potential source of heterogeneity when necessary. RESULTS: This meta-analysis included 17 studies with 4049 patients, of whom 2248 (55.5%) underwent ELAPE and 1801 (44.5%) underwent APE. There were no statistical differences regarding the circumferential resection margin positivity (13.0% vs. 16.2%, OR = 0.69, 95% CI = 0.42–1.14, P = 0.15) and post-operative perineal wound complication rate (28.9% vs. 24.1%, OR = 1.21, 95% CI = 0.75–1.94, P = 0.43). The ELAPE was associated with lower rate of intraoperative perforation (6.6% vs. 11.3%, OR = 0.50, 95% CI = 0.39–0.64, P < 0.001) and local recurrence (8.8% vs. 20.5%, OR = 0.29, 95% CI = 0.21–0.41, P < 0.001) when compared with APE. CONCLUSIONS: The ELAPE was associated with a reduction in the rate of intra-operative perforation and local recurrence, without any increase in the circumferential resection margin positivity and post-operative perineal wound complication rate when compared with APE in the surgical treatment of low rectal cancer.