Multi‐center study of endoscopic revision after side‐by‐side metal stent placement for malignant hilar biliary obstruction

The recent development of ultra-thin delivery systems, which enable simultaneous insertion of two metal stents, has encouraged wider adoption of side-by-side (SBS) stent placement for malignant hilar biliary obstruction (MHBO). However, the management of stent occlusion after SBS placement has not been well-characterized. This study aimed to examine the outcomes of endoscopic reintervention (E-RI) after SBS placement in patients with MHBO.Sixty-seven patients who underwent E-RI for stent occlusion after SBS placement between 2013 and 2020 at three tertiary-care referral centers were investigated. We evaluated the technical success, clinical success, recurrent biliary obstruction (RBO), and adverse events other than RBO rates associated with E-RI. Furthermore, the factors associated with successful E-RI were also evaluated.The technical success and clinical success rates were 79.1% (53/67) and 76.1% (51/67), respectively. Early adverse events other than RBO occurred in 4.5% (3/67) and late events in 3.9% (2/51). The RBO rate after E-RI was 52.9% (27/51), and the median time to RBO after E-RI was 85 days. Common bile duct (CBD) diameter (odds ratio 2.62; 95% confidence interval, 1.37-5.01; P = 0.003) and metastatic disease (odds ratio, 0.11; 95% confidence interval, 0.02-0.64; P = 0.015) were independently correlated with E-RI success in the multivariate analysis.This study demonstrated that E-RI after SBS placement is technically feasible and safe, but the success rate was significantly lower in patients with narrow CBDs and metastatic diseases. These factors may be useful for the selection of the initial stenting method.