Delayed vs Immediate Coloanal Anastomosis after Total Mesorectal Excision for Low Rectal Cancer: An International Multicenter Retrospective Cohort Study

BACKGROUND: Despite increasing interest in Turnbull–Cutait pull-through delayed coloanal anastomosis (DCAA) for low rectal cancer, its advantages over conventional immediate coloanal anastomosis (ICAA) with a diverting stoma remain unclear. This study aimed to compare postoperative outcomes between DCAA and ICAA after elective total mesorectal excision for low rectal cancer. STUDY DESIGN: This international, multicenter, retrospective cohort study included patients who underwent elective minimally invasive total mesorectal excision with hand-sewn coloanal anastomosis (ICAA or DCAA) for primary low rectal adenocarcinoma. The primary outcome was the overall 30-day postoperative complication rate. Postoperative anorectal function was assessed using the low anterior resection syndrome and Wexner scores 1 and 2 years postoperatively. RESULTS: A total of 305 consecutive patients (109 delayed and 196 immediate) were assessed. The overall 30-day postoperative complication rate was 25%, with a significantly lower incidence in the DCAA group compared with the ICAA group (15% vs 31%, p = 0.002). Both early (within 30 days) and late (after 30 days) anastomosis-related complications were significantly lower in the DCAA group than that in the ICAA group, at 7% vs 15%, p = 0.047, and 2% vs 11%, p = 0.005, respectively. Two years postoperatively, the DCAA cohort had a significantly lower proportion of patients with major low anterior resection syndrome (38% vs 60%, p = 0.018) and severe incontinence (0% vs 8%, p = 0.029). CONCLUSIONS: DCAA without a diverting stoma for low rectal cancer removes the risks associated with stoma creation and closure-related morbidity. DCAA is also linked to significantly lower postoperative morbidity and improved anorectal function at 2 years compared with ICAA with a diverting stoma. DCAA may therefore be the optimal anastomotic method for patients with low rectal cancer.