Endobiliary Radiofrequency Ablation: Principles, Technique, and Evidence in Cholangiocarcinoma

Endobiliary radiofrequency ablation (RFA) has emerged as a promising adjunct to biliary stenting in the palliative management of unresectable extrahepatic cholangiocarcinoma. By generating localized thermal injury through a high-frequency alternating current (400–500 kHz) delivered via an intraductal electrode, RFA induces coagulative necrosis of malignant tissue, aiming to delay tumor ingrowth, maintain ductal patency, and improve quality of life. The procedure can be performed during endoscopic retrograde cholangiopancreatography or percutaneously, using bipolar probes advanced over a guidewire under fluoroscopic control. Technical success depends on adequate positioning of the electrodes within the stricture, correct energy settings (7–10 W for 60–120 s), and appropriate stent selection. Preclinical studies demonstrated controlled necrosis extending through the bile-duct wall, while clinical investigations have evaluated its impact on outcomes. Early retrospective series and several randomized controlled trials showed that RFA combined with stenting prolongs stent patency and, in selected subgroups, improves survival compared with stenting alone, without increasing the overall rate of complications. Meta-analyses have confirmed a consistent benefit in stent function and a moderate survival advantage, particularly in distal malignant strictures, although results remain heterogeneous due to differences in technique, patient selection, and stent type. The most frequent adverse events are cholangitis, pancreatitis, and acute cholecystitis. Overall, endobiliary RFA is a safe, technically feasible, and clinically relevant option to enhance biliary drainage in advanced cholangiocarcinoma. Standardization of procedural parameters and prospective trials are still needed to better define its therapeutic role and identify patients most likely to benefit.