Prognostic value of circulating CD34+ cells in myelodysplastic syndromes

We studied circulating (C)CD34+ cells by flow cytometry in 96 patients with myelodisplastic syndromes (MDS) at diagnosis, and in a subset of 35 cases during follow-up. CCD34+ counts were stratified within both International Prognostic Scoring System (IPSS) and World Health Organization (WHO) categories. Counts >10/μl were associated with poorer leukemia-free survival, a prognostic value for evolution independent from that of WHO, and a higher progression probability within intermediate-risk IPSS and WHO classes. When serial measurements were performed, counts >10/μl more frequently correlated to evolution. Separating newly diagnosed patients on the basis of 10/μl cut-off of circulating CD34+ cells retains prognostic utility, especially in intermediate-risk MDS.