Radiation Therapy for Liver and Biliary Tract Cancers.

Primary liver and biliary tract cancers remain major causes of global cancer mortality, with liver and intrahepatic bile duct cancers accounting for 866,136 new cases and 758,725 deaths worldwide in 2022. Curative surgery, transplantation, ablation, embolotherapy, and systemic therapy have improved outcomes, but many patients remain limited by cirrhosis, liver reserve, vascular invasion, biliary obstruction, anatomic constraints, or advanced presentation; population-level survival remains poor for both liver and bile duct cancers. Modern radiation therapy has emerged as an important local and regional modality for hepatocellular carcinoma, intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma, and gallbladder cancer.