A Multicenter Prospective Study on the Safety and Efficacy of the New Low Axial Force Self-Expandable Metallic Stent...

Self-expandable metallic stents are widely used for malignant colorectal obstruction, and low axial force (AF) stents have been developed to reduce adverse events. The Niti-S Enteral Colonic Uncovered Stent (MD/BB type) is a new low-AF stent that maintains a 22 mm outer diameter despite using a 9Fr delivery system. This improves placement performance and reduces adverse events. We aim to evaluate the efficacy and safety of this stent.

In this prospective, multicenter clinical study, we assess the efficacy and safety of the low-AF Niti-S MD/BB stent for colonic stenting. Of the 199 consecutive registered patients who underwent colorectal stenting with the Niti-S MD/BB stents at 12 centers affiliated with the Japan Colonic Stent Safe Procedure Research Group between February 2019 and March 2023, 193 were included for analysis. The primary endpoint was the clinical success rate. The secondary endpoints included technical success and adverse events.

The technical success rate was 98.4% (190/193), and the clinical success rate was 95.9% (185/193). In all bridge-to-surgery cases, elective surgery was successfully performed as planned, and no perforations were observed. In palliative cases, three perforations occurred. Seven patients required surgery in the subsequent year due to adverse events. The 1-year stent patency rate in PAL cases was 80.6%.

This new low-AF Niti-S MD/BB stent demonstrated excellent safety and efficacy, with high technical and clinical success rates and a low incidence of adverse events. Thus, low-AF stents may be a safe, user-friendly option for obstructive colorectal cancer.