Immunophenotypes in adult acute lymphocytic leukemia. Role of flow cytometry in diagnosis and monitoring of disease.

Flow cytometry has revolutionized the study of hematopoietic cells. Immunophenotyping by multiparameter flow cytometry supplements conventional morphologic diagnosis by providing information on cell lineage and differentiation in ALL and helps monitor disease by improving sensitivity in detecting minimal residual disease. The use of multiple MoAbs and multicolor study by flow cytometry has revealed heterogeneity among ALL and mixed-lineage acute leukemia, which are assigned to the same diagnostic categories by morphology. As technology has improved, clinical and research applications of flow cytometry have expanded to include evaluation of nuclear markers, oncogene proteins, apoptosis, cytokine receptors, and drug resistance. Expanded identification of MoAbs against leukemia-specific markers and the use of QFCM be a significant in managing patients with ALL in the future. In addition, flow cytometry and flow cytometric sorting will be combined more and more with other technologies, such as molecular probing or fluorescence in situ hybridization (FISH). The sorting of rare malignant cells based on immunophenotype and subsequent confirmation by PCR or FISH has already been proven feasible. Ultimately, it is hoped that further definition of subgroups of ALL by immunophenotyping using prognostically significant markers and the use of hybrid technologies of flow cytometry and molecular analysis or cytogenetics will improve treatment strategies for patients with ALL.