Prognostic relevance of the flow cytometric count of medullar blasts in myelodysplastic syndromes.

Objective The medullar blast count is a milestone in the prognostic assessment in myelodysplastic syndromes ( MDS). The optical microscopy ( OM) may sometimes be inaccurate in this disease. The aim of this work is to test the flow immunocytometric ( FCM) determinations of medullar immature cells ( CD45^±) and the expression, among them, of CD33, CD34, and CD117 markers, for their prognostic relevance. Methods In a retrospective analysis of 98 patients affected by MDS, the IPSS was re-calculated by means of the FCM determination of blasts. Survival of patients at low or intermediate-1 IPSS risk was compared with the survival of patients at intermediate-2 or high IPSS risk. In the 64 cases with OM blast count lower than 5%, the survival of patients with the FCM count of medullar blasts ≤2% was compared with that of patients with FCM count >2%. Results Each single marker had a prognostic weight comparable to the optical blast count. The FCM blast count was particularly efficient in distinguishing the risk of having up to 2% or more than 2% of blasts in patients without OM excess of blasts. Conclusion This method is interesting as prognostic tool, especially in patients without excess of blast. [ABSTRACT FROM AUTHOR]