Repeated Endobiliary Radiofrequency Ablation Plus Durvalumab, Gemcitabine, and Cisplatin for Unresectable Extrahepatic Cholangiocarcinoma

Extrahepatic cholangiocarcinoma (eCCA) frequently presents as unresectable disease with obstructive jaundice. Although gemcitabine, cisplatin plus durvalumab (GCD) is the global standard first-line regimen, median overall survival remains approximately one year. Endobiliary radiofrequency ablation (EB-RFA) is biologically plausible to enhance local tumor control by inducing coagulative necrosis at the biliary stricture. Retrospective studies, including a multicenter dataset from participating institutions, suggest a survival benefit of repeated EB-RFA, especially when combined with systemic therapy. However, prospective randomized evidence is lacking.

This trial (BRAVE) randomizes eligible patients to EB-RFA plus standardized endoscopic stenting or endoscopic stenting alone, followed by GCD. A planned second endoscopic session is performed at Month 3 (window 2-4 months). Additional EB-RFA sessions (≥2-month intervals) are permitted in the EB-RFA arm if imaging shows potentially ablatable lesions and clinical benefit is expected.

The study aims to determine whether repeated EB-RFA prolongs survival and improves biliary patency when integrated with modern systemic therapy.

Inclusion criteria

Histologically or cytologically confirmed extrahepatic cholangiocarcinoma (eCCA).

Unresectable disease (unresectable due to tumor/patient factors, or patient refusal of surgery).

Biliary obstruction requiring drainage, demonstrated by abnormal cholestatic liver tests, elevated bilirubin, radiologic evidence, or existing biliary drainage.

Planned initiation of first-line systemic therapy with durvalumab + gemcitabine + cisplatin (GCD).

Age ≥18 years.

Able to provide written informed consent.

Exclusion criteria

Prior radiotherapy or systemic therapy for the current eCCA.

Presence of a self-expanding metal stent that cannot be endoscopically removed.

Surgically altered anatomy except for Billroth-I; prior biliary reconstruction.

History of chronic cholangitis (e.g., primary sclerosing cholangitis, IgG4-related cholangitis).

Expected survival <3 months.

Inability to insert an oral endoscope or reach the papilla.

Contraindication to endobiliary RFA.

Pregnancy or possible pregnancy.

Any condition judged unsuitable by the investigator.