Plasmacytoma of the stomach: diagnosis with the aid of immunoperoxidase technique.

A gastric tumor, originally diagnosed as a plamacytoma in 1953, but in which the diagnosis was disputed, has been re-examined by the immunoperoxidase staining technique. The demonstration of a single type of immunoglobulin in the tumor cells is considered conclusive evidence of its neoplastic nature. Two further cases of gastrict plasmacytoma encountered in recent months have also been examined by this technique and similar results obtained. The pathology of plasma cell tumors is discussed and a brief review of the literature is added with regard to the management and the overall poor prognosis.