An abnormal pancreatico-choledocho-ductal junction in cases of biliary tract carcinoma.

A histopathologic study on how the common bile duct and main pancreatic duct open into the duodenum was performed on 72 autopsied cases of biliary tract carcinoma. Type IIIb which was considered to be an abnormal pancreatico-choledocho-ductal junction was identified in 8 of 34 cases in common bile duct carcinoma and in 4 of 24 cases in gallbladder carcinoma, while none of the control cases belonging to Type IIIb. In cases of Type IIIb, reflux of pancreatic juice may occur into the bile duct and produce the repeated inflammation on the biliary tract. Therefore, the abnormal pancreatico-choledocho-ductal junction was suggested to be one of the pathogenic factors which cause biliary tract carcinoma.