Intrahepatic cholangiocarcinoma
(ICC), a tumor with biliary tract differentiation pathologic features, is the
second most common primary liver cancer worldwide after HCC, accounting for 15-20% of all primary liver cancers; the incidence of ICC is on the rise, especially in Western Countries.
The morphologic classification system for primary liver
cancer proposed by the Liver Cancer Study Group of Japan divides ICC into three
types based on macroscopic appearance: the mass-forming type, the periductal
infiltrative type, and the intraductal growing type. Mass-forming ICC (IMCC) is
the most common type and shows a radial growth pattern, invading into the
adjacent hepatic parenchyma.