Primary gastric malignant lymphoma. A morphological and immunohistochemical study of 38 cases.

Thirty-eight cases of primary gastric malignant lymphoma were studied morphologically and immunohistochemically. The Working Formulation was used for classification of non-Hodgkin's lymphoma (1). The results indicated that 37 cases were non-Hodgkin's lymphoma while the remaining case was Hodgkin's disease. Thirty-three cases (89%) of non-Hodgkin's lymphoma were considered to be of B cell origin and 2 cases (5%) of histiocytic origin. No case was considered to be of T cell origin. We suggest that the majority of primary gastric malignant lymphomas are derived from follicular center cells, and that gastric plasmacytoma is not as rare as previously described.