Immunohistochemical studies on B cell lymphomas with special reference to T cell infiltration and its significance as a prognostic factor.

Twenty-eight cases of B cell lymphoma were studied immunohistochemically utilizing a panel of monoclonal antibodies. Of 27 cases tested, 26 were B-1-positive and 22 of 24 cases were HLA-DR positive. There were eight BA-1-positive cases, including one follicular lymphoma, and 10 J-5-positive cases including five diffuse large cell lymphomas. Some of the J-5-positive diffuse large cell lymphomas were considered to be of follicular center cell origin. Infiltration and distribution of non-neoplastic T cell subsets, BA-1-positive B cells, dendritic reticulum cells, Langerhans cells and HNK cells showed close similarity between the structure of follicular lymphomas and that of the reactive follicles. Such similarity to the normal counterpart structure was less apparent in diffuse lymphomas, especially in the large cell type. These findings were interpreted to be an expression of different degrees of neoplastic deviation. There was evidence to suggest that, regardless of the histological classification, a large number of infiltrating non-neoplastic T cells was related to good prognosis.