The upward trend in the immunotherapy utilization for hepatobiliary cancers

Hepatobiliary cancers(HBCs)include those of the liver[mainly hepatocellular carcinoma(HCC)and intrahepatic cholangiocarcinoma]and biliary tract(extrahepatic cholangiocarcinoma and gallbladder cancer).Based on the 2020 global cancer statistics,liver cancer ranks seventh in incidence and third in mortality among all malignant tumors,while gallbladder cancer ranks 25th in incidence and 21st in mortality(1).Due to the lack of typical symptoms and signs at the early stages,HBCs are often diagnosed at intermediate or advanced stages,and thus the opportunity of curative surgical interventions is missed(2).Therefore,most patients with HBC can only be treated with noncurative treatments,including immunotherapy.Several immunotherapeutic approaches have been attempted for HBCs,including oncolytic viruses,tumor vaccines,adoptive immunotherapy,and immune checkpoint inhibitors(ICIs;Figure 1).