Immunotherapy in biliary tract cancers: Current landscape and emerging directions

Biliary tract cancers (BTCs), which include intrahepatic and extrahepatic cholangiocarcinomas as well as gallbladder carcinomas, are aggressive malignancies with a poor prognosis. Standard therapies such as surgical resection and chemotherapy offer limited survival benefits, particularly in advanced stages. Immunotherapy has recently emerged as a promising new treatment approach in the management of BTCs. This review provides a detailed analysis of the immunobiology of BTCs, highlighting the evidence supporting the use of ICIs either alone or in combination with chemotherapy. It also discusses emerging immunotherapeutic strategies, response biomarkers, ongoing clinical trials, and potential future directions.