Gastric plasmacytoma: report of a case.

A 54-year-old man with primary gastric plasma-cytoma is herein reported. After the patient had been diagnosed as having malignant lymphoma by gastrofiberscopy and a radiologic upper GI examination, a total gastrectomy was performed. Both histological and immunohistochemical studies showed plasmacytoma cells infiltrating the entire stomach wall, producing IgM-lambda, and indicating a final diagnosis of primary gastric plasmacytoma. Monoclonal immunoglobulin was not detected in the serum throughout the course. The case is discussed with reference to other reported cases of primary gastric plasmacytoma.