Safety and efficacy of metal stents for malignant colonic obstruction in patients treated with bevacizumab

The aim of this study was to examine clinical outcomes and adverse events (AEs) of self-expandable metal stents (SEMSs) in the management of malignant colonic obstruction (MCO). Patients with SEMSs for MCO treated at our institution from 2007 to 2016 were included. Clinical success was defined as successful oral intake after the procedure and technical success as stent deployment across the stricture in the desired location. Of 199 patients, the mean age was 58, 54% were men, and 99% had stage IV cancer. MCO etiology was colorectal cancer in 82% and extrinsic compression in 17%. Technical success was achieved in 99.5% and clinical success in 89%. The SEMSs were palliative in 97% and were a bridge to surgery in 4%. MCO occurred in the left side of the colon in 90%, transverse in 4.5%, and ascending colon in 5.5%. SEMSs were placed in curved segments in 30% and straight segments in 70%. Tandem SEMSs were required in 27 patients. Forty-six patients had 48 AEs (24%), including 2% periprocedure, 15% postprocedure, and 83% after 72 hours. Stent-related AEs (n = 25) included persistent obstruction (n = 14), occlusion (n = 10), and failure of expansion (n = 1). Procedural AEs (n = 23) included minor bleeding (n = 2), perforations (n = 4), abdominal pain (n = 12), stent migration (n = 4), and respiratory insufficiency (n = 1). Repeat procedures were performed in 21 of 46 patients. After SEMSs, 48 patients underwent surgery, including resection with primary anastomosis (n = 8), resection with definitive stoma (n = 18), and diverting stoma without resection (n = 19). Mean time to surgery after SEMS placement was 175 days. Postsurgical AEs occurred in those with resections (leak, 2; infection, 2). Of 104 receiving bevacizumab, 22% had AEs, including 1 perforation compared with 3 in the nonbevacizumab group (P = .549). Mean overall survival was 5.6 months. Extrinsic compression and curved strictures were associated with poor clinical success by univariate analysis and etiology (noncolonic with poor outcome) by multivariate analysis. SEMSs for MCO has high technical but suboptimal clinical success. Curved strictures and extrinsic compression are associated with poor outcomes. The perforation rate was not higher in the bevacizumab compared with the nonbevacizumab group, although this should be further validated in a larger population.