T-cell prolymphocytic leukemia. Clinical and immunologic characterization

The clinical course of a patient with extensive skin involvement due to T-cell prolymphocytic leukemia is described. The malignant cells isolated from the patient's blood and skin were studied utilizing cytochemical analysis and multiple monoclonal antibodies directed against cell surface antigens. The leukemic cells displayed a surface antigen phenotype similar to that of normal post thymic suppressor T-cells. On the basis of this study together with the few published reports, it appears that T-prolymphocytic leukemia is derived from lymphocytes demonstrating either the suppressor or helper phenotype, and that extensive dermal infiltration may be independent of phenotypic classification. Although T-prolymphocytic leukemia shares certain morphologic, cytochemical, and immunologic features with chronic lymphocytic leukemia, it is an aggressive disease with an average survival of approximately 6 months and is best thought of as a distinct pathologic entity.