A Case of Pancreatic Serous Cystadenoma Penetrating Bile Duct Requiring Differentiation from Malignancy.

A 67-year-old man was admitted to our hospital with jaundice. A closer examination revealed that he had obstructive jaundice due to bile duct obstruction caused by a multifocal cystic tumor of the pancreas. Endoscopic retrograde cholangiopancreatography (ERCP) revealed stenosis of the distal bile duct and leakage of contrast medium into the pancreatic cyst. Pancreaticoduodenectomy was performed, and a pinhole fistula was found connecting the cyst and the bile duct. Histological examination led to the diagnosis of serous cystadenoma (SCA). Herein, we report a rare case of SCA with obstructive jaundice and penetration of the bile duct, which was treated by radical resection.