Review of Mass-Forming Intrahepatic Cholangiocarcinoma

Abstract

The incidence of intrahepatic cholangiocarcinoma (iCCA) is highest in Eastern countries, such as Thailand, South Korea, and China, but its incidence and mortality are increasing worldwide. Over recent decades, the worldwide age-standardized incidence for iCCA has been steadily increasing, whereas that for perihilar CCA and distal CCA has been decreasing. The macroscopic growth pattern of CCA is somewhat different according to the anatomic location of the tumor. iCCA can show three main patterns of growth: mass forming, periductal infiltrating, and intraductal growing. Morphologic classification is important to understand the mode of tumor spread, which is critical in predicting a tumor’s resectability and in planning the extent of surgery. Furthermore, different macroscopic growth types are resulting in different imaging findings and different list of differential diagnosis. This review provides a comprehensive and critical overview of current knowledge and what is envisaged on the horizon for iCCA, focusing on mas-forming type. 1. Tumor growth pattern 2. Histological subtype of iCCA 3. Imaging phenotype and differential diagnosis of iCCA 4. Staging of iCCA 5. Preoperative prognostic prediction of iCCA