Morphological and immunohistochemical investigation of non-Hodgkin's lymphoma combined with Hodgkin's disease.

Twenty cases with a morphological picture highly suspicious for a combination of non-Hodgkin's lymphoma and Hodgkin's disease were investigated. The infiltrates of Hodgkin's disease differed from those of non-Hodgkin's lymphoma in their cellular component of Hodgkin and Sternberg-Reed cells and the irregularity in the fibre pattern. Based upon histological and immunohistochemical criteria the 20 cases were divided into three groups. Group 1 (n = 10) contained seven chronic lymphocytic leukaemias of B type, one lymphoplasmacytoid immunocytoma, and two centroblastic/centrocytic lymphomas. The non-Hodgkin's lymphoma components showed a monotypic immunoglobulin distribution pattern and/or leukaemic blood picture. Adjacent to the non-Hodgkin's lymphoma was typical Hodgkin's disease in which Hodgkin and Sternberg-Reed cells were positive for both immunoglobulin light chains and IgG and reacted with anti-CD15. Group 2 (n = 5) consisted exclusively of centroblastic/centrocytic lymphoma in combination with Hodgkin's disease in which the few Hodgkin and Sternberg-Reed cells were negative with anti-CD15 monoclonal antibody. Group 3 (n = 5) consisted of four chronic lymphocytic leukaemias of B type and one lymphoplasmacytoid immunocytoma. In these cases no combination with Hodgkin's disease could be diagnosed apart from the presence of partially CD15 positive Hodgkin and Sternberg-Reed cells. The following conclusions were drawn: anti-CD15 (LeuM1 and 3C4/C3D-1) can neither confirm nor exclude Hodgkin's disease since, while they do not detect Hodgkin and Sternberg-Reed cells in all cases of Hodgkin's disease, they do recognize Hodgkin and Sternberg-Reed cells in some B-cell lymphomas; anti-CD30 (Ber-H2) reacted with Hodgkin and Sternberg-Reed cells in all cases of Hodgkin's disease and also detected these cells in cases of non-Hodgkin's lymphoma.