Insights into the origin of intrahepatic cholangiocarcinoma from mouse models.

Cholangiocarcinoma is a malignant cancer of the bile ducts that can be anatomically classified as intrahepatic (ICC), perihilar (PCC), or extrahepatic (ECC). ICC is the second most common primary liver cancer (PLC) (1) and is beset by late diagnoses and poor prognoses, with the overall 5-year survival less than 5% (2, 3). Unfortunately, the incidence and mortality of ICC continues to increase in the United States and around the world while treatment strategies are limited (4-6). In Asian countries with the highest incidence of ICC (30-40 per 100,000), particularly Thailand, the major risk factor is the infection of liver fluke (7), while in Western countries with lower incidence (5 per 100,000), risk factors include hepatitis B virus, hepatitis C virus, biliary lithiasis, cirrhosis, alcohol abuse, obesity, and diabetes (7, 8).