Clinicopathologic and experimental studies on cases of abnormal pancreatico-choledocho-ductal junction.

An abnormal pancreatico-choledocho-ductal junction, in which free communication between the pancreatic duct and the common bile duct was present, was observed in 17 out of 120 cases (14.2%) of biliary tract carcinoma and in all of four cases of congenital biliary dilatation, but in noe of about 200 control patients without biliary tract disease. Outstanding findings in the pancreas, such as degeneration of the ductal epithelium and interlobular fibrosis, were found in 6 of 21 cases of abnormal junction. In an experimental study using 63 puppies given choledocho-pancreatic end-to-side ductal anastomosis, dilatation of the bile duct of varying degree occurred and mucosal hyperplasia of the biliary tract was observed in 12 of 25 anastomosed dogs for a duration of more than one month. Cell kinetics in biliary tract mucosa observed by the use of monoclonal antibody against bromodeoxyuridine (BrdU) was obviously elevated in dogs subject to long-term follow-up. As for pancreatic lesions, the incidence and histologic findings were similar to those of human studies, as follows: chronic pancreatitis in only a few animals, mild periductal parenchymatous change in 15 puppies and no significant change in 44 puppies. Therefore, an abnormal pancreatico-choledocho-ductal junction may be one of the significant factors producing biliary dilatation, biliary tract carcinoma and pancreatitis.