Risk factor for cholangiocarcinoma all except
High-Yield Explanation
Chronic typhoid carrier develops reccurent cholangitis which progresses to sclerosing cholangitis, with subsequent development of cholangiocarcinoma. Chronic ulcerative colitis is associated with sclerosing cholangitis which increases the risk of developing cholangiocarcinoma by 20 fold compared with normal population. Parasitic infestations like Clonorchis sinensis,Liver fluke etc induces DNA changes,mutations through production of free radicals and carcinogens & stimulate cellular proliferation and invasive cancer. Reference:SRB's manual of surgery,5th edition,page no: 661;Bailey & Love's sho practise of surgery,25th edition,page no:1128.