A number of pathologic conditions, however, resulting in either acute or chronic biliary tract epithelial injury may predispose to malignant change.

Primary sclerosing cholangitis, an idiopathic inflammatory condition of the biliary tree, has been associated with the development of cholangiocarcinoma in up to 40% of patients.

Chronic biliary tract parasitic infection, seen commonly in Southeast Asia due to Clonorchis sinensis and Opisthorchis viverrini, has also been identified as a risk factor.

[9] Although gallstones and cholecystectomy are not thought to be associated with an increased incidence of cholangiocarcinoma, hepatolithiasis and choledocholithiasis may predispose to malignant change.

Further, industrial exposure to asbestos and nitrosamines, and the use of the radiologic contrast agent, Thorotrast (thorium dioxide), are considered to be risk factors for the development of cholangiocarcinoma.