Hybrid robot-assisted surgery versus conventional fully robotic surgery for colon cancer: study protocol for a multicenter, parallel-group, single-blind randomized controlled superiority trial

BACKGROUND: Robot-assisted surgery (RAS) for colon cancer offers technical advantages but is frequently associated with prolonged operative time and higher procedural costs compared with laparoscopy. A hybrid approach that incorporates laparoscopic devices (clips, advanced bipolar devices, and staplers) during selected steps while maintaining robotic dissection may improve operative efficiency and reduce device-related costs. However, high-level randomized evidence comparing Hybrid RAS with fully robotic colectomy is lacking. METHODS: This is a multicenter, single-blind, randomized controlled superiority trial. A total of 120 patients with resectable colon cancer (cecum, ascending colon, sigmoid colon, or rectosigmoid; clinical stage I–IIIC) will be enrolled and randomized 1:1 to either fully robotic surgery (control) or Hybrid RAS using laparoscopic clips, advanced bipolar devices, and staplers (intervention). Randomization will be centralized and stratified by institution, sex, and tumor location (right vs. left colon). The primary endpoint is operative time (minutes), defined as time from skin incision to completion of wound closure. Secondary endpoints include anastomosis time, blood loss, intraoperative adverse events related to devices, postoperative recovery milestones, laboratory markers on postoperative day 3, complications within 30 days (Clavien–Dindo), pathological outcomes, surgeon/assistant stress and satisfaction scores, recurrence-free survival, overall survival, and device-related surgical costs. Analyses will follow the intention-to-treat principle. DISCUSSION: This trial will determine whether Hybrid RAS can shorten operative time while maintaining safety and oncologic adequacy. TRIAL REGISTRATION: Japan Registry of Clinical Trials (jRCT): jRCTs052240215; registered on 12th December 2024.