Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Bile Duct Cancer (Cholangiocarcinoma) ?
    ### Response:
    Key Points
                    - Bile duct cancer is a rare disease in which malignant (cancer) cells form in the bile ducts.     - Having colitis or certain liver diseases can increase the risk of bile duct cancer.    - Signs of bile duct cancer include jaundice and pain in the abdomen.
    