All of the following increase risk for cholangio carcinoma except
Long standing history of sclerosing cholangitis associated with chronic ulcerative colitis increases the risk of developing cholangiocarcinoma by 20 fold than the normal population. Parasitic infestations like Clonorchis sinensis induces DNA changes and mutations through production of carcinogens and free radicals & stimulate cellular proliferation and invasive cancer. Reference:SRB's manual of surgery,5th edition,page no:661
Ulcerative colitis
Gall stones in CBD
Sclerosing cholangitis
Chlonorchis
G.I.T