Robotic‐assisted colectomy for right‐sided colon cancer: Short‐term surgical outcomes of a multi‐institutional prospective cohort study in Japan

Abstract Background In Japan, there are no substantial reports on robotic‐assisted colectomy because few institutions performed the procedure, as it was not covered by national insurance until March 2022. Aim This study aimed to evaluate the safety and feasibility of robotic‐assisted colectomy for patients with curatively resectable colon cancer in Japan. Methods This multi‐institutional, prospective, single‐arm, observational study enrolled patients diagnosed with curatively resectable clinical stage I–IIIC colon adenocarcinoma with D2 or D3 lymph node dissection and treated with robotic‐assisted colectomy. The primary endpoint was the conversion rate to laparotomy. The non‐inferiority of outcomes for robotic‐assisted colectomy versus laparoscopic colectomy, which was determined from historical data, was verified. Results One hundred patients were registered between July 2019 and March 2022 and underwent robotic‐assisted colectomy performed by seven expert surgeons at six institutions. Thirteen patients were excluded because their surgeons had insufficient experience performing robotic‐assisted colectomy; therefore, 87 patients were eligible for the primary endpoint analysis. There was no conversion in these 87 patients, and robotic‐assisted colectomy was non‐inferior to laparoscopic colectomy in terms of conversion rate (90% confidence interval 0–3.38, p = 0.0006). No intraoperative adverse events occurred, and no mortality was observed in a total of 100 patients. The rate of patients with Clavien–Dindo complications grade III or higher was 4%. Conclusion This study showed the non‐inferiority of the conversion rates between robotic‐assisted colectomy and laparoscopic colectomy. Favorable perioperative outcomes also suggest the safety and feasibility of robotic‐assisted colectomy.