Intrahepatic cholangiocarcinoma and mixed tumors

Abstract

Intrahepatic cholangiocarcinoma (ICC) represents the second most common primary liver tumor after hepatocellular carcinoma. These tumors arise from the bile ducts epithelium, peripheral to the secondary bifurcation of the left or right hepatic duct. Although most cholangiocarcinomas occur sporadically, the disease incidence is higher, and it develops earlier in the patients with primary sclerosing cholangitis (PSC), choledochal cyst, Caroli disease, clonorchiasis, and viral hepatitis (especially type C). According to their growth pattern, ICCs can be classified into three types: mass-forming, periductal-infiltrating, or intraductal-growing cholangiocarcinoma. Imaging plays the most important role in preoperative characterization of ICC with mass-forming type presenting as lobulated hypovascular lesions causing retraction of liver capsule and peripheral bile duct dilatation. Periductal-infiltating type is very difficult for timely diagnosis and is usually discovered in follow-up of PSC patients as worsening of dominant stricture. Intraductal-growing cholangiocarcinoma is the rarest type of ICC with much better outcome than other ICC forms. It presents usually as polypoid lesion filling the bile ducts with proximal biliary dilatation.