Intrahepatic cholangiocarcinoma (ICC) primarily originates from the epithelial cells of the intrahepatic bile ducts and is mostly classified as adenocarcinoma. It accounts for approximately 10% of primary liver malignancies. Malignant tumors that originate simultaneously from both intrahepatic bile ducts and hepatocytes are referred to as mixed-type carcinomas, which are relatively rare.
Epidemiological evidence indicates that ICC is associated with hepatitis C virus (HCV) infection, HIV infection, liver cirrhosis, and diabetes mellitus. The clinical manifestations of ICC are similar to those of hepatocellular carcinoma. The most common symptoms include pain in the right upper quadrant and weight loss, with approximately 25% of patients presenting with jaundice. AFP levels are typically normal in ICC patients, though elevated levels of CEA or CA19-9 may be observed in some cases. On CT and MRI, ICC typically appears as a focal hepatic mass, and dilatation of bile ducts surrounding the tumor may be present. On contrast-enhanced imaging, the tumor may exhibit peripheral or central enhancement. This disease often infiltrates and grows along the bile ducts, and at the time of diagnosis, intrahepatic or lymph node metastasis may already be present.
The most effective treatment for ICC is liver resection, although the five-year survival rate after surgery is less than 50%. Poor prognostic factors include intrahepatic metastasis, lymph node metastasis, vascular invasion, and positive surgical margins. Some efficacy has been observed with immunotherapy combined with targeted drug therapy.