Comparison of Minimally Invasive Colectomy Between Intra- Versus Extra-Corporeal Anastomosis Technique (COMMIT Study): Short-Term Analysis.

Aim: To compare the operative and short-term outcomes between intracorporeal anastomosis (IA) and extracorporeal anastomosis (EA) in minimally invasive colectomy. Methods: This multicenter cohort study used data from the Kyoto Colorectal Surgery Study Group database. Patients who underwent minimally invasive colectomy between 2018 and 2025 were included. Primary outcome was the incidence of intraoperative blood loss ≥ 200 mL. Secondary outcomes included continuous intraoperative blood loss, the incidence of intraoperative blood loss ≥ 100 and ≥ 300 mL, intraoperative blood transfusion, operative time, resection margins, harvested lymph node yield, and postoperative complications. Propensity score matching was performed to balance baseline characteristics. Results: Of 3213 eligible patients, 928 and 2285 underwent IA and EA, respectively. After the propensity score matching, 650 matched pairs were identified. The incidence of intraoperative blood loss ≥ 200 mL was significantly lower in the IA group than that in the EA group (2.5% vs. 4.9%; risk difference, -2.46%; 95% confidence interval, -4.65% to -0.43%), whereas continuous intraoperative blood loss was comparable. Although operative time was generally longer for IA, subgroup analysis demonstrated significant effect modification according to surgical approach, with operative time tending to favor IA. The incidence of adequate resection margins tended to be higher in IA, although the difference was not statistically significant. Harvested lymph nodes and postoperative complications were generally comparable. Conclusion: IA was associated with a lower incidence of intraoperative blood loss ≥ 200 mL during minimally invasive colectomy. These findings indicate that IA may reduce the occurrence of relatively high blood loss events.