In-stent radiofrequency ablation with uncovered metal stent placement for tumor ingrowth/overgrowth causing self- expandable metal stent occlusion in distal malignant biliary obstruction: multicenter propensity score-matched study

Abstract

Background and aims: In patients with unresectable malignant biliary obstruction (MBO), endoscopic drainage with a self-expandable metal stent (SEMS) is a well-established treatment, but stent patency is limited. This study aimed to evaluate the efficacy of in-stent radiofrequency ablation (IS-RFA) followed by uncovered SEMS placement for the management of occluded SEMSs.Methods: From 2016 to 2020, 48 patients with recurrent biliary obstruction due to tumor ingrowth or overgrowth after SEMS placement for pancreatobiliary cancer in 3 tertiary hospitals were analyzed. For distal MBO, patients in the RFA group were treated with IS-RFA and uncovered SEMS placement, and those in the control group were treated with un-covered SEMS placement alone. Patients in both groups were matched on the basis of propensity scores in a 1:1 ratio.Results: The median time to recurrent biliary obstruction (TRBO) was 117 days in the RFA group and 82.5 days in the control group (P = .029). No significant differences in median overall survival were detected between the 2 groups (170 days vs 72 days; P = .902). No significant adverse events were reported after the second SEMS placement in either group, but 2 cases of mild cholangitis were reported in the control group. Ablation was interrupted in 5 patients (35.7%) of the RFA group owing to in-stent contact, but sufficient ablative energy was delivered in the majority of the patients (92.9%) after IS-RFA was repeated in the same session.Conclusions: IS-RFA followed by an uncovered SEMS is safe and feasible and may improve TRBO as a stent revi-sion for occluded SEMSs in pancreatobiliary cancer. (Gastrointest Endosc 2023;97:694-703.) [GRAPHICS]