Fifteen cases of Hodgkin's disease of nodular and diffuse paragranuloma subtype (nodular and diffuse subtype of lymphocyte predominant type of Hodgkin's disease) were studied by light and electron microscopy, using monoclonal antibodies recognizing T and B-lymphocytes and dendritic reticulum cells. The results were compared with findings on 10 cases of Hodgkin's disease of mixed type with lymphocyte predominance. The present study provides evidence that paragranuloma represents a special variant of Hodgkin's disease different from other subtypes. Paragranuloma is characterized by predominance of B-cells which were demonstrated with a new B cell reagent KiB3 on routinely processed paraffin sections.