Efficacy of a Novel Dual-Layer Plastic Stents for Malignant Biliary Obstruction

Objectives: In hepatopancreatic diseases, stenting is widely employed to manage cholangitis and obstructive jaundice. Stent materials are primarily categorized as plastic or metal. Plastic stents have notable advantages, such as reduced likelihood of peripheral bile duct obstruction, a lower cost, and the ease of replacement compared to metallic stents. However, their patency period is shorter due to narrower diameters. Plastic stents are typically composed of materials like polyurethane or polyethylene. To improve patency, new dual-layer stents combine polyurethane with polytetrafluoroethylene (PTFE). PTFE, used in the inner layer, is expected to prevent biofilm formation. This study aimed to assess the clinical efficacy of this dual-layer stent. Methods: A retrospective analysis was performed on 48 cases (Group R) using REGULUS^® from November 2022 to November 2023 and 30 cases (Group IS) using inside-type plastic stents from January 2020 to November 2023 for malignant hilar and intrahepatic bile duct obstructions. Stent patency and clinical outcomes were compared between the groups. Results: There was no significant difference in the recurrent biliary obstruction (RBO) rate between the groups (p = 0.644). The time to recurrent biliary obstruction (TRBO) was 74 days in Group R and 118 days in Group IS, with no significant difference (p = 0.219). Conclusions: The dual-layer stent placed across the papilla demonstrated comparable clinical outcomes to inside-type stents. The PTFE inner layer likely reduces biofilm formation, enhancing patency. Across-the-papilla placement may facilitate reinterventions in challenging cases, broadening stent options.