Background and objectives. Diagnosis of myelodysplastic syndromes (MDS) is based on evaluation of blood cell counts, as well as on morphological features of hematopoietic cells and distinct cytogenetic abnormalities. As about half of cases are cytogenetically “silent” and the results of morphological analysis are sometimes indefinite there is a need for additional objective method to establish the diagnosis of MDS. Flow cytometry can be used to define the percentage of blasts and their phenotype, as well as the regularity of granulocyte, monocyte and erythrokaryocyte maturation patterns and may serve as a powerful tool for the clarification of diagnosis.
Materials and methods. 56 adult patients with MDS in suspicion treated at Vilnius University Hospital Santaros Klinikos were included in the study. Diagnostic bone marrow samples were analyzed on FACS Canto flow cytometer applying 6 color marker panel.
Results. Four deviations from normal phenotype or maturation patterns in blast, granulocyte, monocyte or erythrokaryocyte populations were proven to sufficiently discriminate MDS positive and negative cases. In this setting the specificity of the assay was 73.3% and the sensitivity was 80.0%. These findings were: reduced B-cell precursors count (p=0.03), reduced side scatter of granulocyte population (p=0.10), changes of CD10/CD64 and CD11b/CD13/CD16 expression pattern on granulocyte population (p=0.03 and p<0.01 respectively), and changes of CD71/CD235a expression pattern on erythrokaryocyte population (p=0.05).
Conclusions. Flow cytometry can be applied to differentiate cytopenias and to identify patients with higher risk of MDS as a part of integral diagnosis.