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What is All of the following are known predesposing factors for cholangiocarcinoma except : and explain in detail?
Answer is A (CBD stone) : Cholelithiasis is not clearly a predisposing factor for Cholangiocarcinoma - Harrison The predisposing factors of cholangiocarcinoma include : I. Chronic hepato-biliary parasite infection (Clonorchiasis or Asiatic cholangio-hepatitis) Q Congenital Anomaly with ectatic ducts (Choledochal cyst).Q Sclerosing cholangitis Q Ulcerative colitis Occupational exposure to carcinogensQ(Rubber + Automotive plants) Note: Nodular lesions that arise at the bifitrcation of hepatic ducts are called Klastskin tumors. Q