[Value of immunologic phenotyping of acute leukemias in children].

Immunologic typing has demonstrated considerable heterogeneity among the acute leukemias. The most significant recent advance has been development of monoclonal antibody techniques. Some markers identified using these techniques seem to be specific for a given stage of maturation of one lymphoid or myeloid cell line. Most acute lymphoblastic leukemias (ALLs) are malignant proliferations whose differentiation appears to have become 'stuck' at one stage of maturation. Results of immunologic typing correlate well with the other clinical and biological data. For prognostic purposes, several patterns can be identified. Among B line ALLs, four varieties have been differentiated, i.e., CD10 negative ALLs, common ALLs, pre-B ALLs, and B ALLs. T ALLs include a broad spectrum of heterogeneous proliferations whose immunologic classification is made difficult by the large number of phenotypes encountered. Among acute myeloblastic leukemias (AMLs), some highly undifferentiated forms have been recognized, by means of immunologic typing, as originating in one of the myeloid cell lines. However, the nosologic and prognostic significance of these studies is less obvious than in ALLs.