Comparison of Minimally Invasive Colectomy Between Intra‐ Versus Extra‐Corporeal Anastomosis Technique ( COMMIT Study): Mid‐Term Analysis

Aim: The adoption of intracorporeal anastomosis (IA) in minimally invasive colectomy for colon cancer has increased; however, its mid-term oncological outcomes compared with those of extracorporeal anastomosis (EA) remain unclear. Methods: This multicenter retrospective cohort study analyzed patients who underwent minimally invasive curative colectomy for colon cancer between 2018 and 2022 from the Kyoto Colorectal Surgery Group database. Propensity score matching (1:4) was applied to balance patient, tumor, and surgical characteristics between IA and EA groups. Primary outcome was 2-year recurrence-free survival (RFS). Secondary outcomes included 2-year cumulative incidence of peritoneal, anastomotic, and distant recurrence, and postoperative complications. Results: = 1651), matching yielded 224 IA and 862 EA cases with well-balanced baseline covariates. After matching, the 2-year RFS tended to be better in the IA group (hazard ratio [HR], 0.66; 95% confidence interval [CI], 0.41-1.06), though not statistically significant. The incidences of peritoneal and anastomotic recurrence were similar between the groups (risk difference [RD], 0.13%; 95% CI, -0.76% to 1.02%; and RD, -0.25%; 95% CI, -0.61% to 0.10%, respectively), whereas distant recurrence was lower in the IA group (RD, -4.79%; 95% CI, -6.75% to -2.83%). Subgroup analyses suggested a greater reduction in distant recurrence in patients with advanced tumors. Conclusion: IA demonstrated a comparable risk of peritoneal and anastomotic recurrence and suggested a potential reduction in distant recurrence without an associated deterioration in 2-year RFS. These findings support IA as an oncologically reasonable option, even for advanced-stage tumors.