IntroductionrnPrimary liver cancer, the second most common cause of cancer related death worldwide1, presents ethnic, etiological, sex, and geographical diversity2 (Figure 1A). At the histological level, liver cancer includes two major types:hepatocellular carcinoma (HCC, about 80%) and cholangiocarcinoma (CCA, about 15%). Many etiological factors contribute to HCC development, such as hepatitis B virus (HBV), hepatitis C virus (HCV), aflatoxin B1 (AFB1), alcohol, and metabolic diseases3. By contrast, the major risk factors for CCA are liver flukes (Opisthorchis viverrini and Clonorchis sinensis) and primary sclerosing cholangitis4, although HBV, HCV, and metabolic diseases may also be linked to CCA (Figure 1A). According to their anatomical locations, CCA can also be classified as intrahepatic (ICC), perihilar (PCC), and extrahepatic (ECC) tumors (Figure 1B).