The impact of several phenotypic features at diagnosis on survival of patients with myelodysplastic syndromes

Multiparametric flow cytometry is a useful co-criterion for diagnostic confirmation of MDS in patients with peripheral cytopenias and a normal karyotype. We examined the impact on patients' survival of several phenotypic aberrancies detected by a small 4-color panel of monoclonal antibodies (MoAbs). Diagnosis of the patients (54) was made by WHO criteria using peripheral blood counts, bone marrow (BM) morphology and karyotype. Flow cytometry was performed at diagnosis, and features obtained were compared to normal BM (24). We could detect 16 alterations: 4 in granulocytic precursors, 4 in monocytes, 6 in CD34(+) cells, beside changes in plasmacytoid dendritic cells and basophil precursors. The total number of changes in RAEB was higher (median 8) than in cases with <5% BM blasts (median of 5). Maturation abnormalities in myeloid precursors, increase in basophils and decrease of B-cell precursors showed a similar frequency in all types of MDS, but the number of phenotypic abnormalities in CD34+ cells and monocytes were more common in RAEB. In the survival analysis, WHO type (p = 0.001), IPSS (p = 0.004), degree of anemia (p = 0.007), a higher BM blast percentage in cytology (p <0.0005), higher numbers of total CD34(+) cells (p < 0.0005), CD34(+)/CD13(+) (p = 0.0006) and CD34(+)/CD13(+) cells (p = 0.0002), as well as a higher total number of phenotypic abnormalities (p = 0.004) were associated to a shorter survival. However, in the multivariate analysis, only IPSS and the number of changes in CD34+ cells (but not the overall number of abnormalities) were independent risk factors for a shorter survival. Our panel was sufficient to confirm the diagnosis of MDS and permitted to detect independent prognostic features.