A case of multicentric gastric carcinoids without hypergastrinemia.

We have encountered an unusual case of gastric carcinoid tumors. Gastroscopic examination of a 71-year-old male patient showed eight smooth protrusions at the greater curvature of the gastric body, some of which had central depressions. Endoscopic ultrasonography demonstrated that the largest tumor (2.6 cm in diameter) was located in the submucosal layer. The patient had a normal serum gastrin level and was negative for antiparietal cell antibody. The patient was also found to have a pituitary tumor, an adenomatous goiter, and bilateral Warthin's tumors of the parotid glands. Histological examination of the resected stomach identified 12 discrete carcinoid tumors. There was no evidence of atrophic gastritis or of endocrine cell micronests. No mutations of the MEN1 gene were found on genomic DNA analysis. Despite the multiplicity of carcinoid tumors, we diagnosed type 3 gastric carcinoid in this patient.