Cholangiocarcinoma represent a diverse group of epithelial cancers based on the anatomical presentation:
Intrahepatic CCA – bile duct within the liver
Perihilar (hilar CCA) – outside the liver (extrahepatic)
Distal CCA – extrahepatic
Most Cholangiocarcinomas are well, moderately and poorly differentiated adenocarcinomas and are graded as either, well differentiated, moderately or poorly differentiated tumors.
Grading systems differ depending on the type of cancer. In general, tumors are graded as 1, 2, 3, depending on the amount of abnormality.
Well differentiated (low grade) G -1 – the cells and the organization of the tumor tissue appear close to normal; tend to grow and spread slowly.
Moderately differentiated (intermediate grade) – G-2 – moderate tumor growth
Poorly differentiated (high grade) – G -3 – tend to grow rapidly and spread faster than tumors with a lower grade.
Note: Combined hepatocellular and cholangiocarcinoma is classified as hepatocellular carcinoma (HCC) however, The World Health Organization (WHO) a specialized agency of the United Nations (UN) just recently classified hepatocelluar cholangiocarcinoma carcinoma as a cholangiocarcinoma subtype.
Marion