Abstract
A 56-year-old man visited our hospital with a chief complaint of epigastric pain. He was admitted for further examination and treatment after a 15-mm tumor was detected in the gallbladder on abdominal contrast-enhanced CT. Eudoscopic ultrasonography showed gallbladder mucosal hyperplasia and three elevated lesions with a maximum size of 12 mm. While endoscopic retrograde cholangiopancreatography showed no pancreaticobiliary maljunction, accessory pancreatic duct imaging showed reflux into the bile duct of the contrast agent that had been infused into the main pancreatic duct. In addition, the amylase level in the bile collected from the gallbladder was 111,400 IU/L, and the cytological diagnosis was Class III. The patient was diagnosed with a gallbladder polyp complicated by pancreatobiliary reflux without pancreaticobiliary maljunction, and cholecystectomy was performed. Histopathological findings included a hyperplastic polyp with a high-grade atypia. Pancreatobiliary reflux is diagnosed based on bile amylase levels or secretin-stimulated MRCP, but in the present patient, accessory pancreatic duct imaging also contributed greatly to the diagnosis. Patients with pancreatobiliary reflux without pancreaticobiliary maljunction are at high risk for gallbladder cancer, and they require prophylactic cholecystectomy and postoperative follow-up keeping occurrence of biliary tract cancer in mind.
