Diagnostic Utility of Flow Cytometry in Myelodysplastic Syndromes

Abstract

The pathological hallmark of myelodysplastic syndromes (MDS) is marrow dysplasia, which represents the basis of the WHO classification of these disorders. This classification provides clinicians with a useful tool for defining the different subtypes of MDS and individual prognosis. The WHO proposal has raised some concern regarding minimal diagnostic criteria particularly in patients with normal karyotype without robust morphological markers of dysplasia (such as ring sideroblasts or excess of blasts). Therefore, there is clearly need to refine the accuracy to detect marrow dysplasia. Flow cytometry (FCM) immunophenotyping has been proposed as a tool to improve the evaluation of marrow dysplasia. The rationale for the application of FCM in the diagnostic work up of MDS is that immunophenotyping is an accurate method for quantitative and qualitative evaluation of hematopoietic cells and that MDS have been found to have abnormal expression of several cellular antigens. To become applicable in clinical practice, FCM analysis should be based on parameters with sufficient specificity and sensitivity, data should be reproducible between different operators, and the results should be easily understood by clinicians. In this review, we discuss the most relevant progresses in detection of marrow dysplasia by FCM in MDS.

Keywords: Diagnostic Tools; Flow Cytometry; Myelodysplastic Syndrome.

Figure 1

Detection of marrow dysplasia by analysis of four cardinal parameters of marrow dysplasia for from a single cell aliquot stained with CD34 and CD45 antibodies. A) bone marrow from representative MDS patients showing an increase of CD34+ myeloblasts, a decrease of CD34+ B cell progenitors, a reduced SSC in granulocytic cells and an aberrant expression of CD45 on myeloblasts; B) Healthy donor bone marrow.