Prospective observational study investigating the factors impacting the safety of endoscopic right-sided colectomy...

Right-sided colon resection is generally regarded as a relatively safe laparoscopic procedure with a low complication rate. Paradoxically, right hemicolectomy has been reported to carry a fourfold higher mortality rate compared to low anterior resection for rectal cancer in Japanese real-world data, despite the latter being more technically demanding and associated with a higher complication rate. This study aims to investigate the factors that influence the safety of laparoscopic right-sided colon resection.

Patients undergoing laparoscopic or robot-assisted surgery for right-sided colon cancer at participating institutions in the Laparoscopic Colorectal Resection Study Group will be prospectively enrolled between 3 July 2024 and 31 May 2026. This multicenter study expects to enroll a total of 2,000 colorectal cancer cases from 73 facilities nationwide. The primary endpoint is the incidence of postoperative complications classified as Clavien-Dindo grade ≥ III. Risk factors contributing to these severe complications will be analysed. As a key secondary endpoint, the incidence and predictors of intraoperative vascular injury near the superior mesenteric vein will also be evaluated.

This nationwide, multicentre, prospective study (SCaRLET study) will provide critical insights into the safety of laparoscopic and robot-assisted right-sided colectomy. By evaluating 2,000 cases under standardised conditions, the study aims to clarify the actual incidence and causes of severe postoperative complications and intraoperative vascular injuries, which remain poorly understood despite the procedure's perceived safety. Comprehensive data collection and adherence to routine clinical practice will support accurate risk assessment and enhance the generalizability of findings. The results are expected to inform best practices and contribute to improving surgical safety in colorectal procedures including indication of colectomy both in Japan and internationally.

This study was registered in the Japan Registry of Clinical Trials on 3 July 2024 (jRCT1010240021).