Cholangiocarcinoma refers to malignant tumorsthat develop in epithelial lining of biliary system,andit is divided into two categories according to tumorlocation,intrahepatic cholangiocarcinoma(ICC)andextrahepatic cholangiocarcinoma(ECC).ICC occursfrom the epithelial cells of the intrahepatic bile duct,its branches and interlobular biliary tree;and ECC is Cholangiocarcinoma refers to malignant tumors that develop in epithelial lining of biliary system, and is divided into two categories according to tumor location, intrahepatic cholangiocarcinoma (ICC) andextrahepatic cholangiocarcinoma (ECC) .ICC occursfrom the epithelial cells of the intrahepatic bile duct, its branches and interlobular biliary tree; and ECC is