Abstract
Collection of large numbers of cases of pancreaticobiliary maljunction (PBM) has shown that PBM without bile duct dilatation is frequently associated with gallbladder carcinoma. Surveys over the last decade, however, show that the incidence of bile duct cancer in PBM without dilatation is not as rare as that of choledochal cyst. The pathology in PBM is a result of reflux of pancreatic juice and stasis of the mixture in the biliary system. The bile acid fractions of bile are altered, and the presence of mutagens has been demonstrated. Dysplasia and hyperplasia are often found in the epithelia of PBM, and proliferative activity is increased, as evidenced by an increased PCNA labeling index and ODC labeling index. Furthermore, K-ras gene mutations, overexpression of p53 protein, p53 gene mutations and p53 LOH have been demonstrated even in nonneoplastic epithelia, especially of bile ducts without dilatation. Judging from the statistical data and the molecular biological data, total resection of an extrahepatic bile duct with gallbladder should be the treatment of choice for the prevention of carcinogenesis, regardless of whether dilatation is present or not. Hepaticoduodenostomy is preferable because it is a less invasive procedure and preserves natural bile flow into the intestinal tract. The incidence of postoperative complications, such as anastomotic stricture and or reflux cholangitis, is low even in cases without dilated bile ducts.
