Role of flow cytometry in pediatric hematopathology.

Multiparameter flow cytometry with optimally selected antibody combinations has expanded the use of this technique beyond traditional applications in hematopathology. By analyzing qualitative patterns of antigen expression on discrete populations or "clusters," one can detect immunophenotypic aberrancy in specific cell populations relative to normal and reactive populations. Evaluation of patterns of antigen expression can also be used to supplement conventional methodologies in the diagnosis and subclassification of certain types of hematologic neoplasia. Finally, the diagnosis of some congenital disorders affecting the hematolymphoid system can be facilitated by the detection of characteristic immunophenotypic changes. Examples of applications of multiparameter flow cytometry with particular relevance to pediatric hematopathology are discussed.