[The immunology of CD4-negative skin hematosarcomas]

A wide panel of monoclonal antibodies to hematopoietic cell differentiation antigens was applied to the study of CD4-negative skin hematosarcomas on cryostat secretions. The most frequent CD4-negative type was the B-cell one identified in 6 of 10 cases. In this type the use of monoclonal antibodies in addition to standard immunoglobulin markers seemed to be very important. T-cell type (CD3+ CD8+), histiocytic variant (CD11+Ia+), pseudolymphoma (polyclonal markers pattern), and Kaposi's sarcoma (hematopoietic cell negative antigen) were identified in 1 case each. The authors emphasize the importance of immunological studies of hematosarcomas because of the high frequency of the generalization of B-cell lymphomas; such studies may also help in the differential diagnosis between pseudolymphoma and hematosarcoma.