Anomalous union of the pancreaticobiliary ductal system without dilation of the common bile duct or tumor: case reports and literature review.

Among 698 patients subjected to endoscopic retrograde cholangiopancreatography, an anomalous union of the pancreaticobiliary ductal system (AUPBD) was found in 6 patients (0.9%). One of these 6 patients had an associated congenital choledochal cyst, and 4 did not. Two of these 4 patients, however, had advanced gallbladder cancer. The remaining 2 patients had no associated carcinoma of the biliary tract. A clinicopathological study was performed on these 2 patients and 26 such cases have been reported in the literature. The diagnosis of AUPBD was made by direct cholangiography. Regarding the type of union, the Pancreatic-Biliary type was present in 15 of 18 (83.3%) of these patients. Fifteen of 28 patients (53.6%) had right upper abdominal pain. Thickness of the gallbladder wall was visualized in 26 of the 28 (92.9%) patients. Gallstones were present in 4 (14.3%). AUPBD should always be kept in mind when a patient with abdominal pain is diagnosed as having gallbladder wall thickness without gallstones. ERCP should be performed in these patients in order to detect AUPBD without dilation of the bile duct. This may allow early detection of carcinoma of the biliary tract.