A case of a rare anomaly of the common bile duct associated with an abnormal arrangement of the pancreaticobiliary ductal union.

A 39 year-old Japanese female patient with a duplication of the distal portion of the common bile duct is presented herein. Moreover, an abnormal arrangement of the pancreaticobiliary ductal union, congenital biliary dilatation and carcinoma of the gallbladder were all demonstrated by cholangiographic and endoscopical studies. The patient underwent radical surgery for advanced adenosquamous carcinoma of the gallbladder, and her postoperative course was satisfactory. A reflux of pancreatic juice into the bile duct was demonstrated, but it was eliminated and considered to be a contributory etiologic factor of the gallbladder carcinoma.