Multidimensional Flow Cytometry for Detection of Rare Populations in Hematological Malignancies

Abstract Objective Flow cytometry is becoming an important tool in the characterization of different hematological disorders. The aim of our study was to detect very rare populations in hematological malignancies using the comprehensive concept of immunophenotyping. Patients and Methods Six patients, including three with acute myeloid leukemia, one with acute lymphoblastic leukemia, one with myelodysplastic syndrome, and one with B-cell lymphoma, were enrolled in this study. Serial bone marrow aspirates were analyzed by three-color multidimensional flow cytometry. Results The core principles for the use of flow cytometric analysis are understanding deviations in abnormal antigen expression from normal cellular differentiating pathways and characterizing different patterns of antigenic aberrancy for each patient. Our results demonstrate that multidimensional flow cytometry can be used to: (1) monitor minimal residual disease after treatment; (2) aid in the differential diagnosis of cases, which are difficult to evaluate using conventional morphology; and (3) help in the staging of lymphoproliferative disorders. Conclusion After selecting appropriate combinations of monoclonal antibodies, and applying advanced knowledge in immunophenotyping, flow cytometry is very sensitive and specific for the detection of rare populations in hematological disorders.