Efficacy of fully covered self-expanding metal stents removal versus stent-in-stent techniques in recurrent malignant distal biliary obstruction

Fully covered self-expandable metal stents (FCSEMSs) are widely used in managing malignant distal biliary obstruction (MDBO). However, recurrent biliary obstruction (RBO) has become a significant challenge due to improved patient survival with advanced chemotherapy. This multicenter retrospective cohort study evaluated revision techniques for FCSEMS dysfunction in 159 patients with MDBO initially treated with FCSEMSs. Patients were categorized into four groups based on the revision method: stent exchange with self-expandable metal stents (SEMS, n = 53) or plastic stents (n = 23), and stent-in-stent placement with SEMS (n = 51) or plastic stents (n = 32). All procedures achieved 100% technical and clinical success. The primary time to recurrent biliary obstruction (TRBO) showed no significant difference among the groups (mean: 148 days, 95% confidence interval [CI]: 127-170 days). However, secondary TRBO differed significantly (p = 0.014): 161 days (SEMS, stent exchange), 53 days (plastic stent, stent exchange), 104 days (SEMS, stent-in-stent), and 67 days (plastic stent, stent-in-stent). Multivariate analysis revealed that stent-in-stent placement with SEMS increased the risk of RBO compared to SEMS stent exchange (hazard ratio [HR]: 6.53, 95% CI: 1.89-22.55, p = 0.003). Additionally, revision within 180 days was associated with a higher risk of RBO (HR: 1.77, 95% CI: 1.10-2.86, p = 0.019). Overall survival was comparable across all groups. These findings suggest that SEMS stent exchange after FCSEMS removal is an effective revision method for RBO in MDBO, providing improved secondary stent patency without increasing adverse events or affecting overall survival.