Surgical strategy for patients with pancreaticobiliary maljunction without choledocal dilatation.

It is well known that the frequency of an associated gallbladder cancer in patients with pancreaticobiliary maljunction (PBM) without congenital choledochal dilation (CCD) is very high, while that of bile duct cancer with CCD is remarkably high, and that of bile duct malignancy without CCD is low. However, recent statistical evaluations have demonstrated that the coincidence rates of gallbladder and bile duct cancer with CCD are 11.5% and 4.6%, respectively, whereas without CCD the rates are 57.1% and 4.1%, respectively. Rates of bile duct cancer with CCD are comparable to those without CCD. We have performed biliary reconstruction after resection of extrahepatic bile ducts along with the gallbladder for PBM patients who had neither CCD nor cancer. Our surgical strategy for these patients without CCD with PBM was assessed from K-ras point mutations and overexpression of p53 protein in the epithelia of the cancerous portions and non-neoplastic portions of the gallbladder and bile duct affected by PBM regardless of choledochal dilatation. The mutation rate in the non-neoplastic gallbladder epithelium without CCD was 80%, that of the bile duct without CCD 57%, not significantly different from the 50% and 40%, respectively, with CCD. The frequency of p53 overexpression in the non-neoplastic bile duct epithelium without CCD was 14%, comparable to the 11% in gallbladder epithelium with CCD. Judging from the statistical data and the molecular biological data, resection of an extrahepatic bile duct with the gallbladder should be the treatment of choice for carcinogenesis prevention.