Long-Term Stoma-Free Outcomes After Diverting Stoma Closure Following Radiation-Based Neoadjuvant Treatment for Rectal Cancer.

AIM: Long-term stoma-free outcomes after diverting stoma closure in patients who underwent sphincter-preserving rectal cancer surgery with double-stapling technique (DST) reconstruction following radiation-based neoadjuvant treatment remain unclear. We evaluated delayed re-stoma-free survival, causes of delayed re-stoma creation, and final stoma status. METHODS: This retrospective cohort study included patients who underwent sphincter-preserving rectal cancer surgery with double-stapling technique reconstruction and diverting stoma creation following radiation-based neoadjuvant treatment between 2011 and 2024. The primary outcome was delayed re-stoma-free survival after initially successful stoma closure. Delayed re-stoma was defined as re-stoma creation more than 30 days after closure. RESULTS: Among 296 patients, 168 received radiotherapy without additional preoperative systemic chemotherapy (non-TNT), and 128 received total neoadjuvant therapy (TNT). Stoma closure was achieved in 287 patients (97.0%). Five required re-stoma creation within 30 days, leaving 282 with initially successful closure. During a median post-closure follow-up of 63 months, delayed re-stoma creation occurred in 25 patients (8.9%): structural anastomotic complications in 14, functional disorders in seven, tumor recurrence in three, and dysmotility-related megacolon in one. Estimated delayed re-stoma-free survival was 93.3% at 3 years and 90.3% at 5 years, with no significant difference between the non-TNT and TNT groups (log-rank p = 0.176). At the last follow-up, 258 patients (87.2%) were stoma-free. CONCLUSION: Approximately 90% of patients were stoma-free at the final follow-up. Delayed re-stoma creation was most commonly attributable to structural anastomotic complications. Long-term stoma-free status should be considered a clinically meaningful endpoint beyond stoma closure alone.