Clinical Factors for Successful Total Colonoscopy after Self-Expandable Metallic Stent Placement as a Bridge-to-Surgery in Patients with Obstructive Colorectal Cancer.

Objectives: Colonic self-expandable metallic stents (SEMSs) are widely used for preoperative decompression in obstructive colorectal cancer (CRC) patients undergoing total colonoscopy (TCS). However, the factors influencing the success of TCS and the risk of perforation remain unclear. This study aimed to identify key determinants of successful TCS after SEMS placement. Methods: We retrospectively analyzed the clinical data of 48 patients who underwent placement of an 18 mm diameter colorectal SEMS as a bridge to surgery (BTS) at a single center between November 2017 and November 2023. Clinical success was defined as successful TCS regardless of endoscopist or scope change. Patients were divided into successful and unsuccessful TCS groups. The effects of tumor (location, stenosis, depth, and peritoneal dissemination) and procedural variables (timing of TCS, stent size, colonoscope type, and performing endoscopist) were analyzed. Results: The mean patient age was 72 years, and 71% were male. The clinical success rate of TCS was 77% (37/48). Univariate analysis revealed that tumor invasion depth (T4) was significantly associated with TCS failure (odds ratio [OR]: 0.23, P=0.0427). Smaller-diameter colonoscopes were correlated with higher success rates. Synchronous cancers were detected in 10% of the cases. Conclusions: The tumor invasion depth impacts the success of TCS. Smaller-diameter scopes may improve outcomes, particularly with deeper tumor invasion.