CoCStom - Randomised trial comparing completeness of adjuvant chemotherapy after early vs. late diverting stoma closure in low anterior resection for rectal cancer

• Applicant: Dr. Flavius Sandra-Petrescu
• Subject Area: General and Visceral Surgery
• Term: from 2013 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 223460251

Diverting stoma was shown to reduce clinical severity of anastomotic leakage in patients undergoing low anterior resection (LAR) with total mesorectal excision for locally advanced rectal cancer. The standard of care is stoma closure after completion of adjuvant chemotherapy (control group). Two randomized multicentre trials show that early closure (EC) is feasible without a major increase of the complication rate. No information is provided on the influence of EC on completeness of chemotherapy (CoC). Adjuvant chemotherapy represents a cornerstone in the multimodal treatment of locally advanced cancer. An exploratory analysis of a multicentre study suggests that CoC is associated with better oncological outcome. How timing of stoma closure influences CoC is still unclear. EC may have positive (by avoiding stoma related morbidity) or negative (due to postoperative complications) impact on CoC. CoCStom is a randomised multicentre trial comparing CoC as primary endpoint after early (8-10 days after tumor resection) vs. late (~26 weeks after tumor resection after completion of adjuvant therapy) stoma closure in patients with locally advanced rectal cancer undergoing LAR after neoadjuvant therapy. An increase of 20% for the rate of CoC is regarded as a clinically meaningful step forward and serves as basis for the sample size calculation. Quality of life and oncological outcome are key secondary endpoints. CoCStom’s objective is to clarify the optimal timing of stoma closure in the context of adjuvant chemotherapy. 224 of 257 patients have been recruited since December 2013.

• DFG Programme: Clinical Trials
• Co-Investigators: Professor Dr. Ralf-Dieter Hofheinz; Professor Dr. Peter Kienle