Safety and feasibility of combined transanal total mesorectal excision with delayed coloanal anastomosis in high-risk patients with low rectal cancer.

PURPOSE: To evaluate the safety and effectiveness of immediate coloanal anastomosis (ICAA) with diverting ileostomy versus delayed coloanal anastomosis (DCAA) following transanal total mesorectal excision (taTME) in reducing anastomotic leakage (AL) and stoma-related complications in high-risk patients with low rectal cancer.

METHODS

From April 2021 to November 2024, a prospective cohort study enrolled 74 high-risk patients with low rectal cancer. On the basis of surgical strategy preference, patients underwent either taTME with delayed anastomosis (DCAA, n = 35) or taTME with immediate anastomosis and diverting ileostomy (ICAA, n = 39). The primary outcome was AL incidence. Secondary outcomes included postoperative complications, inflammatory markers, and anorectal functional outcomes.

RESULTS

A total of 65 patients were analyzed (DCAA, n = 32; ICAA, n = 33). AL occurred only in the ICAA group (12.1%; five cases: two grade A, two grade B, and one grade C), whereas no AL was observed in the DCAA group. The rate of major postoperative complications (Clavien-Dindo grade ≥ III) was comparable between groups (P > 0.05). C-reactive protein levels were significantly lower in the DCAA group on postoperative days 1 (P < 0.001) and 3 (P = 0.034), with no difference by day 7 (P = 0.185). Wexner and LARS scores at 3 and 12 months did not differ significantly between groups.

CONCLUSION

TaTME with DCAA was associated with a lower incidence of AL and avoidance of stoma-related morbidity compared with ICAA and diverting ileostomy, while maintaining comparable functional outcomes in high-risk patients with low rectal cancer.