A case of multiple gastric carcinoids that could not be preoperatively diagnosed.

Here, we report the case of patient with multiple gastric carcinoids showing histopathological behavior similar to that of type I carcinoid tumors of the stomach. The patient was a 61-year-old man diagnosed as having a gastric tumor, which was revealed by follow-up computed tomography. Upper gastrointestinal endoscopy revealed a protruded tumor in the greater curvature and a small polyp in the anterior wall of the upper stomach. A biopsy revealed gastric carcinoid. Because he refused to be operated for gastric carcinoid, upper gastrointestinal endoscopy was performed 5 months later. A malignant transformation of the gastric carcinoid was strongly suspected. Therefore, the patient was admitted for operation. Laboratory findings were normal. With the diagnosis of type III gastric carcinoid, total gastrectomy was performed. Microscopic examination revealed that the carcinoid tumor was confined to the submucosa and that the small polyp mentioned earlier was also a carcinoid. Microcarcinoids and numerous enterochromaffin-like cell hyperplasias were observed along the muscularis propria of the fundus. The tumor differed from typical type I gastric carcinoids in several ways. Immunohistochemical staining for chromogranin A, synaptophysin, and cytokeratin was positive. However, p53 was absent, and the MIB-1 index was low. Two years after surgery, the patient is alive without recurrence.