Parapapillary choledochoduodenal fistula associated with cholangiocarcinoma.

Parapapillary choledochoduodenal fistula is a rare disorder. We herein report a case of parapapillary choledochoduodenal fistula associated with cholangiocarcinoma. A 61-year-old woman was admitted to our hospital for further examination of a liver tumor. She had no clinical symptoms, but computed tomography scans showed an irregularly contoured liver tumor which was histologically confirmed to be adenocarcinoma, by a needle biopsy examination. Duodenal fiberscopy revealed a fistula orifice 1.0 cm proximal to the orifice of the papilla of Vater, and endoscopic retrograde cholangiography through the fistula showed a communication to the common bile duct. Hypotonic duodenography demonstrated reflux of contrast material into the choledochoduodenal fistula. The bile sample collected from the common bile duct showed extremely high levels of pancreatic enzymes, including amylase, phospholipase-A2, and elastase-I. Furthermore, Helicobacter DNA was detected in bile by polymerase chain reaction (PCR) analysis. This experience suggests to us that parapapillary choledochoduodenal fistula may be a risk factor for biliary tract carcinoma, and surgical management is the treatment of choice for this rare condition, even when the patient has no significant clinical symptoms.