ABSTRACT
An acinar cell carcinoma of the exocrine pancreas is a rare tumor with reported a incidence of 1% to 2% of pancreatic carcinomas. Cases of acinar cell carcinomas with amphicrine features have been reported in recent decades. However, there are no reports of two simultaneous pancreatic masses: an endocrine tumor and, an exocrine tumor. We encountered a 59-year-old female patient presenting with abdominal pain and melena. The acinar cell carcinoma was a 1x1 cm-sized round solid mass in the head of the pancreas. The islet tumor was a 2.5x1.5 cm-sized round mass in the body of the pancreas. The endocrine tumor was nonfunctioning. Melena resulted from the hemosuccus pancreaticus due to a ductal invasion of the acinar cell carcinoma. The patient had a parathyroid adenoma with hyperparathyroidism. Therefore, both the islet tumor and parathyroid adenoma with hyperparathyroidism were strongly suggestive of a MEN I.