Covered self-expandable metal stents are more associated with complications in the management of malignant colorectal obstruction

Background: The use of self-expandable metal stents (SEMS) for the treatment of malignant colorectal obstruction is increasing. However, results of risk factors for its complications are inconsistent. This study aimed to examine the clinical effectiveness of the procedure as well as the complications and risk factors associated with the complications. Methods: Medical records of patients with malignant colorectal obstruction who underwent endoscopic placement of covered or uncovered SEMS were reviewed retrospectively. The procedure was performed by two endoscopists with experience in pancreatobiliary endoscopy. Results: A total of 152 patients were included (102 men; mean age, 70 ± 12.5 years). The procedure was performed for palliative management in 83 patients and performed as a bridge to surgery in 69 patients. There were 111 uncovered stents and 41 covered stents. The technical success rate was 100 % and the clinical success rate 94.1 %. Overall complications were observed in 49 patients (32.2 %) during the follow-up period (median, 98 days; interquartile range, 19-302 days). Obstruction (17.1 %), migration (7.9 %), perforation (5.2 %), bleeding (1.3 %), and tenesmus (0.7 %) were the causes of the complications. Stage IV disease, carcinomatosis peritonei, complete obstruction of the colon, palliative intention, and covered stents increased the complications based on the univariate analysis. Multivariate analysis revealed that complete obstruction of the colon and covered stents were significantly independent risk factors for complications. In the palliative group, Kaplan-Meier analysis showed significantly shorter median duration to the onset of complications in the covered stent group than in the uncovered stent group. Conclusions: Although SEMS in patients with malignant colorectal obstruction is effective both as palliative therapy and as a bridge to surgery, one-third of patients experienced complications. Severity of obstruction and stent type can influence outcomes.