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.