Su1523 A COMBINED SIDE-BY-SIDE AND STENT-IN-STENT METHOD FOR TRIPLE METAL STENTING IN PATIENTS WITH MALIGNANT HILAR BILIARY OBSTRUCTION

Abstract

Self-expandable metal stent (SEMS) placement is recommended for unresectable malignant hilar biliary obstructions (MHBOs), and a recent randomized study showed that bilateral SEMS placement resulted in fewer reinterventions and better stent patency than unilateral SEMS placement. Although bilateral placement of 2 stents is sufficient in many cases, the placement of 3 or more stents is sometimes needed in high-grade MHBOs because of insufficient drainage and/or segmental cholangitis. However, endoscopic placement of 3 branched SEMSs is technically challenging. We examined the feasibility and efficacy of a novel stenting method combining side-by-side and stent-in-stent (SBSIS) placement for MHBO. Between January 2015 and April 2019, 30 consecutive patients with high-grade MHBO underwent SBSIS placement. Following insertion of the 0.025-inch guidewires into the 3 target intrahepatic bile ducts across the stricture, 2 SEMSs delivery systems were simultaneously inserted over the guidewires. The stents were released concurrently or one-by-one and placed in the side-by-side configuration above the level of the duodenal papilla with their distal ends at the same level. The third target bile duct is reached with the guidewire via the mesh of the stent in the same hepatic side, using the initially placed guidewire of the third target duct as a landmark. The third SEMS was subsequently inserted over the guidewire and placed across the stent mesh and the stricture in the partial stent-in-stent configuration. We evaluated the technical success, functional success, recurrent biliary obstruction (RBO), adverse events other than RBO, and reintervention success rates associated with SBSIS placement. The technical success rate was 87% (26/30). Insertion of the third SEMS failed in 4 patients, and the median diameter of the common bile duct (CBD) was significantly smaller in patients in whom technical failure occurred (5 mm vs. 8 mm; P = 0.003). Functional success was achieved in all patients in whom the procedure was a technical success. The rate of adverse events other than RBO was 13% (4/30). As early adverse events, cholangitis and aspiration pneumonia occurred in 1 patient each. As late adverse events, cholecystitis and non-occlusion cholangitis occurred in 1 patient each. The RBO rate was 38% (10/26), and the median time to RBO was 170 days. The success rate of endoscopic reintervention for RBO was 89% (8/9). SBSIS placement showed favorable results and is a promising option in patients with high-grade MHBO requiring triple metal stenting. This method can reduce technical difficulty by avoiding inability of second SEMS placement and reducing the number of passes through the stent mesh. However, if the CBD diameter is narrow, this procedure might not be suitable.