Epidermoid cyst of an intrapancreatic accessory spleen--a case report.

We report an extremely rare case of a splenic epidermoid cyst of the pancreas in a 51-year-old Japanese male with no clinical symptoms. A cystic tumor of the pancreatic tail was detected incidentally by abdominal ultrasonography. The patient was referred to the Gunma University Hospital for further examination of the pancreatic tumor. Upon diagnosis of a benign cystic tumor, a distal pancreatectomy with splenectomy was performed. Microscopically, the multicystic tumor, which was surrounded by the splenic tissue, was located within the pancreatic tissue. The cysts were lined by non-keratinizing squamous epithelium. The diagnosis of an epidermoid cyst occurring in an intrapancreatic accessory spleen was confirmed. To our knowledge, this is the 4th case ever reported in the English literature.