Comparative effectiveness of neoadjuvant therapy combined with stent placement versus stent alone in obstructive colorectal cancer: a multicenter retrospective analysis

Abstract Objective The aim of this study was to evaluate the impact of self-expandable metal stents (SEMS) and neoadjuvant therapy (NAT) for obstructive colorectal cancer (CRC). Methods This multicenter, retrospective study analyzed 154 patients with obstructive CRC from three centers between 2011 and 2025. Patients were allocated to either a NAT combined with SEMS group ( n = 93) or a SEMS-alone group ( n = 61). Short-term procedural outcomes, pathological tumor response, long-term survival, and the impact of the time interval from stenting to surgery were evaluated between groups and across two time periods (2011–2020 vs. 2021–2025). Results Baseline characteristics were largely comparable between groups. The NAT group demonstrated significantly lower intraoperative stoma rates (8.6% vs. 29.0%, P = 0.031) and postoperative complication rates (8.6% vs. 29.0%, P = 0.031) in the 2011–2020, advantages that persisted in the 2021–2025. Pathological assessment revealed a superior tumor response in the 2021–2025, with 20.7% achieving TRG 0–1 and significantly higher rates of T and N downstaging (39.7% and 60.3%) compared to the 2011–2020. Although survival benefits were not significant in the 2011–2020 period, NAT may be associated with a significant improvement in overall survival (OS) in the 2021–2025 cohort ( P = 0.013). Analysis of surgical timing identified an optimal interval of 14–21 days related to OS for the SEMS group, whereas for NAT patients, an interval exceeding 90 days was associated with worse disease-free survival (DFS). Conclusion SEMS-NAT for obstructive CRC may is an important factor for improved surgical quality and OS benefit in 2021–2025. This study provides crucial evidence for optimizing treatment strategy by recommending a surgery interval.