Peroral Cholangioscopy-Guided Endoluminal Radiofrequency Ablation and Metal Stenting for the Treatment of Unresectable Perihilar Cholangiocarcinoma.

Perihilar cholangiocarcinoma is frequently diagnosed at an advanced stage and is often unresectable. Malignant biliary obstruction is a major cause of morbidity and commonly requires palliative biliary drainage. Endoscopic retrograde cholangiopancreatography (ERCP) with stent placement is widely used to relieve obstruction; however, tumor ingrowth and overgrowth frequently result in recurrent biliary stenosis and reduced long-term stent patency. Endoluminal radiofrequency ablation (eRFA) has emerged as an adjunctive treatment to improve local tumor control and maintain biliary drainage. Nevertheless, conventional eRFA is generally performed under fluoroscopic guidance alone, which may limit accurate delineation of tumor extent and precise energy delivery. This video article presents a single-case technical demonstration of a stepwise ERCP-based protocol integrating peroral cholangioscopy (POCS)-guided biliary mapping, targeted tissue sampling, precise eRFA, and self-expandable metal stent (SEMS) placement for unresectable perihilar cholangiocarcinoma. Direct visualization with POCS enables assessment of tumor morphology, identification of tumor boundaries, selective cannulation of involved biliary branches, and targeted biopsy acquisition. Information obtained during biliary mapping is subsequently used to define target ablation segments and guide controlled energy delivery. Following eRFA, SEMS are deployed to restore and maintain biliary drainage. This protocol provides a practical framework for visualization-guided endoscopic management of complex hilar biliary strictures and highlights key procedural steps that may improve treatment precision and procedural reproducibility in selected patients with unresectable perihilar cholangiocarcinoma.