BACKGROUND AND AIM: Endoscopic placement of three branched self-expandable metallic stents (SEMS) for high-grade malignant hilar biliary obstruction (MHBO) 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. METHODS: Between January 2015 and December 2018, 27 consecutive patients with high-grade MHBO underwent SBSIS placement. We evaluated the technical success, functional success, recurrent biliary obstruction (RBO), adverse events other than RBO, and reintervention success rates associated with SBSIS placement. RESULTS: Technical success rate was 85% (23/27). Insertion of the third SEMS failed in four patients, and median diameter of the common bile duct (CBD) was significantly smaller in patients in whom technical failure occurred (5 mm vs 8 mm; P = 0.004). Functional success was achieved in all patients in whom the procedure was a technical success. Rate of adverse events other than RBO was 15% (4/27). RBO rate was 43% (10/23), and median time to RBO was 157 days. Success rate of endoscopic reintervention for RBO was 89% (8/9). CONCLUSION: SBSIS placement showed favorable results and is a promising option in patients with high-grade MHBO requiring triple metal stenting. However, it might be preferable to avoid SBSIS in patients with a narrow CBD. Clinical Trial Registry: UMIN000035721.
BACKGROUND AND AIM: Endoscopic placement of three branched self-expandable metallic stents (SEMS) for high-grade malignant hilar biliary obstruction (MHBO) 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. METHODS: Between January 2015 and December 2018, 27 consecutive patients with high-grade MHBO underwent SBSIS placement. We evaluated the technical success, functional success, recurrent biliary obstruction (RBO), adverse events other than RBO, and reintervention success rates associated with SBSIS placement. RESULTS: Technical success rate was 85% (23/27). Insertion of the third SEMS failed in four patients, and median diameter of the common bile duct (CBD) was significantly smaller in patients in whom technical failure occurred (5 mm vs 8 mm; P = 0.004). Functional success was achieved in all patients in whom the procedure was a technical success. Rate of adverse events other than RBO was 15% (4/27). RBO rate was 43% (10/23), and median time to RBO was 157 days. Success rate of endoscopic reintervention for RBO was 89% (8/9). CONCLUSION: SBSIS placement showed favorable results and is a promising option in patients with high-grade MHBO requiring triple metal stenting. However, it might be preferable to avoid SBSIS in patients with a narrow CBD. Clinical Trial Registry: UMIN000035721.