The coexistence of nodular and diffuse patterns in nodular non-Hodgkin's lymphomas: significance and clinicopathologic correlation.

One hundred and twenty-six cases of nodular lymphoma have been classified cytologically by the criteria of Rappaport, and have been divided into three architectural groups, based on the degree of nodularity. Eighty-five percent of the patients have been followed for at least 5 years after initial therapy. Analysis of actuarial survival curves reveals that patients in the poorly differentiated lymphocytic and mixed histiocytic-lymphocytic categories with the three architectural patterns ("nodular only," "nodular with focal diffuse," and "nodular with diffuse") have similar long-term and disease-free survivals. Nevertheless, any degree of nodularity imparts a more favorable prognosis than diffuse lymphoma of coreresponding cell type. In the small number of patients with a nodular lye than in the other two histiocytic type, associated with diffuse areas, the prognosis is less favorable than in the other two histologic groups. Thus, a nodular lymphoma of so-called histiocytic type with diffuse areas may behave more like a diffuse than nodular lymphoma, and warrants appropriate therapy.