title: Incidence of anomalous union of the pancreaticobiliary ductal system in biliary cancer.
abstract: OBJECTIVE
  This study was intended to clarify the incidence of anomalous union of the pancreaticobiliary ductal system (AUPBD) in patients with biliary cancer.
  
  
  METHODS
  Cholangiopancreatograms of 106 Japanese patients with biliary cancer were investigated for this study. The study included 58 patients with gallbladder cancer and 48 patients with cholangiocarcinoma. AUPBD was defined radiologically as the common bile duct joining the main pancreatic duct above the narrow distal segment. AUPBD was classified into two types: P-C union, the main pancreatic duct entering the common bile duct; and C-P union, the common bile duct entering the main pancreatic duct.
  
  
  RESULTS
  Overall 10 patients (9.4%) had AUPBD, of whom all had gallbladder cancer and no gallstones. Nine of these patients showed P-C union and one patient had C-P union. The incidence of AUPBD in gallbladder cancer (10/58, 17.2%) was significantly higher (p = 0.0018) than that in cholangiocarcinoma (0/48, 0%). Among patients with gallbladder cancer, the mean age of those with AUPBD (56 years old) was significantly lower (p = 0.02) than that of those without AUPBD (65 years old).
  
  
  CONCLUSIONS
  The incidence of AUPBD in gallbladder cancer is significantly higher than that in cholangiocarcinoma. AUPBD, especially the P-C union, may thus promote the development of acalculous gallbladder cancer.
authors.affiliation: Department of Surgery, Niigata University School of Medicine, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Sandoh
authors.forename: Y
authors.initials: Y
authors.lastname: Shirai
authors.forename: K
authors.initials: K
authors.lastname: Hatakeyama
mesh_terms: D000230:Adenocarcinoma / Q000150:complications / Q000453:epidemiology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001650:Bile Duct Neoplasms / Q000150:complications / Q000453:epidemiology*; D001653:Bile Ducts, Intrahepatic; D018281:Cholangiocarcinoma / Q000150:complications / Q000453:epidemiology; D002769:Cholelithiasis / Q000150:complications; D003135:Common Bile Duct / Q000002:abnormalities*; D005260:Female; D005706:Gallbladder Neoplasms / Q000150:complications / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010183:Pancreatic Ducts / Q000002:abnormalities*