Proposals for a Phenotypic Classification of B-Chronic Lymphocytic Leukemia, Relationship with Prognostic Factors

Immunophenotypic analysis was performed in 53 cases of B chronic lymphocytic leukemia using a large panel of monoclonal antibodies recognizing B, T, activation and myeloid antigens. Our results showed four patterns of reactivity: (a) several molecules were constantly expressed: CD19, CD20, CD24, CD37, HLA-DR, mu heavy chain, CD5, CD23, B5, CD32; (b) one antigen, CD11b, was found in 50 to 80% of the cases; (c) some markers were detected in less than 50% of the cases: CD25, CD38, CD71, CD11a, c, CD14b-c; (d) CD2 and CD16 were never detected. From these results, a phenotypic classification in three groups has been proposed and these groups were correlated with the progression of the disease, mainly with the lymphocyte doubling time of less than one year. We hypothesized that the leukemia cells could be at various stages of differentiation and/or activation according to their expression of activation and myeloid markers.