A case of Zollinger-Ellison syndrome produced by gastrinoma in the duodenum accompanied with multiple endocrine neoplasia type 1

A case of Zollinger-Ellison syndrome produced by gastrinoma in the duodenum accompanied by multiple endocrine neoplasia type-1 (MEN-1) is reported. A 46 year-old female underwent distal gastrectomy due to gastric ulcer 5 years ago. As ulceration of the residual stomach recurred, further examination was performed. Hyperprolactinemia, hypergastrinemia, primary hyperparathyroidism, pancreatic tumor, and duodenal carcinoid were evident, and the diagnoses of Zollinger-Ellison syndrome and MEN-1 were established. The origin of the gastrin secretion was suspected to be from the pancreatic tumor, so sampling of the portal blood was performed. As lesion on the gastrinoma in the pancreas could not be identified, total parathyroidectomy was performed for primary hyperparathyroidism. The level of the gastrin secretion, however, remained high. Partial resection of the duodenum for the duodenal carcinoid and a distal pancreatectomy were carried out concurrently. Immunohistochemical study of the anti-gastrin antibody revealed duodenal tumor cells. Initially, the gastrinoma was thought to be in the pancreas, however, the lesion accompanied with MEN-1 and the Zollinger-Ellison syndrome had occurred in the duodenum.