Selective non-diverting strategy after restorative rectal cancer surgery: a single-center experience combining...

The role of routine diverting ileostomy after restorative rectal cancer surgery remains controversial. We evaluated a selective non-diverting strategy implemented together with technical modifications of the anastomosis and an intensified postoperative surveillance protocol. This retrospective single-center study included 300 patients who underwent restorative surgery for rectal cancer between 2017 and 2026. Patients were categorized according to reconstruction technique: end-to-end stapled colorectal anastomosis, side-to-end stapled colorectal anastomosis, or delayed coloanal anastomosis using the Turnbull-Cutait technique. The primary endpoint was clinically relevant anastomotic leakage, defined according to the International Study Group of Rectal Cancer classification as Grade B or C leakage. Fisher exact, chi-square, Mann-Whitney U, and Kruskal-Wallis tests were used as appropriate; 95% confidence intervals (CIs) were calculated for leakage rates. The cohort included 71 end-to-end, 171 side-to-end, and 58 delayed coloanal reconstructions. Clinically relevant leakage occurred in 8/71 patients after end-to-end anastomosis (11.3%, 95% CI 5.0-21.0), 4/171 after side-to-end anastomosis (2.3%, 95% CI 0.6-5.9), and 2/58 after delayed coloanal anastomosis (3.4%, 95% CI 0.4-11.9; p = 0.010). Among non-diverted stapled colorectal anastomoses, clinically relevant leakage was lower after side-to-end reconstruction than after end-to-end reconstruction (1/163 [0.6%] vs. 3/45 [6.7%], p = 0.032). In selected patients, a non-routine diversion strategy combined with optimized anastomotic configuration, routine splenic flexure mobilization when required, delayed coloanal reconstruction for ultra-low tumors, and intensive postoperative surveillance appears feasible. Because several technical and organizational changes were introduced simultaneously, these findings should not be interpreted as proving the independent safety of omitting diversion.