ABSTRACT: BACKGROUND:Right colectomy is the standard surgical treatment for tumors in the right colon and surgical complications are reduced with minimally-invasive laparoscopy compared with open surgery, with potential further benefits achieved with robotic assistance. The anastomotic technique used can also have an impact on patient outcomes. However, there are no large, prospective studies that have compared all techniques. METHODS/DESIGN:MIRCAST is the Minimally-Invasive Right Colectomy Anastomosis Study that will compare laparoscopy with robot-assisted surgery, using either intracorporeal or extracorporeal anastomosis, in a large prospective, observational, multicenter, parallel, four-cohort study in patients with a benign or malignant, non-metastatic tumor of the right colon. Over 2?years of follow-up, the study will prospectively evaluate peri- and postoperative complications, postoperative recovery, hospital stay, and mid-term results including survival, local recurrence, metastases rate, and conversion rate. The primary composite endpoint will be the efficacy of the surgical method regarding surgical wound infections and postoperative complications (Clavien-Dindo grade III-IV complications at 30?days post-surgery). Secondary endpoints include long-term oncologic results, conversion rate, operative time, length of stay, and quality of life. DISCUSSION:This will be the first large, international study to prospectively evaluate the use of minimally-invasive laparoscopy or robot-assisted surgery during right hemicolectomy and to control for the impact of the anastomotic technique. The research will contribute to current knowledge regarding the medical care of patients with malignant or benign tumors of the right colon, and enable physicians to determine which technique may be the most appropriate for their patients. TRIAL REGISTRATION:This study was registered on Clinicaltrials.gov (clinicaltrials.gov identifier: NCT03650517 ) on August 28th 2018 (study protocol version CI18/02 revision A, 21 February 2018).