Malignant islet cell tumor of the pancreas with multiple hormone production and expression of CEA and CA19-9. Report of an autopsy case.

An autopsy case of malignant islet cell tumor of the pancreas is presented. The patient, a 64-year-old woman showed severe hypoglycemia as the initial symptom, and hyperinsulinemia was demonstrated by laboratory examinations. Metastatic tumors in the liver were found by abdominal computed tomography. Autopsy revealed a tumor measuring 6.5 x 3 x 2 cm occupying the pancreas from the body to the tail. From the results of histological and immunohistochemical studies, this was diagnosed as a malignant islet cell tumor producing multiple hormones such as insulin, glucagon, somatostatin and pancreatic polypeptide, as well as expressing the tumor-related antigens CEA and CA19-9. These findings suggested that the tumor cells showed differentiation to both endocrine cells and pancreatic duct cells.