Comparative Study of the Use of Multihole Fully Covered Metallic Stents Versus Uncovered and Partially Covered Metallic Stents in Malignant Biliary Obstruction

Background: Malignant biliary obstruction (MBO) represents a common and challenging complication of advanced hepatobiliary and pancreatic malignancies. Endoscopic biliary drainage using self-expandable metallic stents is currently the standard palliative treatment. However, optimal stent design particularly the degree of coverage and presence of drainage holes remains under investigation. This study aimed to evaluate the endoscopic management of inoperable malignant obstructive jaundice using self-expandable metallic stents. Methods: This randomized controlled clinical trial was conducted at the ERCP Unit, Hepatology, Gastroenterology and Infectious Diseases department, Zagazig University Hospitals, including 60 patients divided equally into three groups (20 patients each) according to the type of metallic stent used; multihole fully covered (MHFC), partially covered (PC), and uncovered (UC) self-expandable metallic stents (SEMS). All patients underwent standardized clinical, laboratory, and imaging evaluation before and after stent placement. Clinical outcomes, biochemical improvement, and stent function were assessed at 3 and 6 months. Results: Baseline demographic and clinical parameters were comparable among the three groups (p>0.05). At 3 months, all groups showed significant symptomatic relief and bilirubin reduction, with 100% stent patency confirmed by imaging. At 6 months, MHFC-SEMS maintained 100% patency and no migration or obstruction, PC-SEMS showed minor migration (5%) but no occlusion, whereas UC-SEMS demonstrated 15% obstruction and reduced stent function (66.7%) (p=0.043). Conclusion: All metallic stent types provided effective long-term palliation in malignant biliary obstruction. However, multihole fully covered SEMS achieved superior long-term patency and the lowest complication rate without migration, suggesting it offers the optimal balance between drainage efficacy and mechanical stability.