Delayed Colo-anal Anastomosis for Rectal Cancer: Pelvic Morbidity, Functional Results and Oncological Outcomes: A Systematic Review

Abstract

BACKGROUND: Delayed colo-anal anastomosis (DCAA) has received renewed interest thanks to its reduction in anastomotic leakage rate without the use of stoma to protect a low rectal anastomosis. The aim of this review was to summarize the available literature on DCAA following rectal cancer resection and to report clinical, oncological and functional results. METHODS: A comprehensive literature review was conducted including MEDLINE/Pubmed, EMBASE, SCOPUS, clinicaltrials.gov and the Cochrane database of systematic reviews through July 2018. The review was conducted according to MOOSE guidelines. Quality was appraised with the methodological index for non-randomized studies (MINORS) tool. RESULTS: Eight observational studies (409 patients) were included. Average MINORS score was 9.6/14 in seven non-comparative studies and 17/22 in one comparative study. Six studies reported no anastomotic leak. Pelvic sepsis/abscess ranged from 0 to 25%. Mortality rate was <3% in seven studies and 12.5% in one. Poor fecal continence was reported in <30% of patients. Need for permanent stoma was ≤2% in six studies. A five-year survival rate ranged from 63.8 to 81% (four studies). Loco-regional recurrence rate ranged from 4.8 to 14.3% at 3 years (four studies) and from 6 to 38.8% at 5 years (three studies). CONCLUSION: DCAA offers an alternative to primary straight colo-anal anastomosis for low rectal cancer. The benefits include reduced risk of anastomotic leakage and pelvic sepsis, and no need for protective ileostomy, with good functional and oncological outcomes. Results of ongoing randomized controlled trials comparing DCAA with straight colo-anal anastomosis and protective stoma are awaited to draw definitive conclusions.