Mucinous cystadenoma of the pancreas 17 years after excision of gallbladder because of a choledochal cyst

A 56-year-old woman who had undergone excision of the gallbladder because of a choledochal cyst had a tumorous lesion of the pancreas identified by upper abdominal ultrasonography, but an operation was not carried out, because there was no apparent increase in the cystic mass and no elevation of serum tumor markers. In October 2001, she was admitted to our hospital to check for malignancy because of elevated levels of the tumor marker Dupan-2. Abdominal enhanced computed tomography and upper abdominal ultrasonography revealed a large multilocular cystic mass in the body to tail of the pancreas. Endoscopic retrograde cholangiopancreatography showed elongation of the common duct that communicates with the common bile duct and the main pancreatic duct, indicating an anomalous arrangement of the biliary and pancreatic duct system. No apparent communications between the cystic mass and the main pancreatic duct were observed. In January 2002, the patient underwent a spleen-preserving distal pancreatectomy, and histopathological and immunohistochemical examinations led to the diagnosis of pancreatic mucinous cystadenoma with ovarian-like stroma. The mucinous cystadenoma was detected 17 years after the operation for the choledochal cyst. To the best of our knowledge, no documented case reports of mucinous cystadenoma of the pancreas associated with a choledocal cyst have been reported to date. We present here the first case report of pancreatic mucinous cystadenoma occurring in the body to tail of the pancreas, associated with a choledocal cyst.