REFRACTORY-ANEMIA WITH SEVERE DYSPLASIA - CLINICAL-SIGNIFICANCE OF MORPHOLOGICAL FEATURES IN REFRACTORY-ANEMIA

Refractory anemia (RA) in myelodysplastic syndromes (MDS) are very het erogeneous diseases regarding their morphology, clinical features and survival, We proposed the new designations 'RA with severe dysplasia ( RASD)' and 'RA with minimal dysplasia (RAminiD)', In our criteria, RAS D is considered present if a bone marrow (BM) examination shows Pseudo -Pelger-Huet anomalies of mature neutrophils greater than or equal to 3% and/or micromegakaryocytes (mMgk) of megakaryocytes greater than or equal to 10% in RA patients, RAminiD is defined as RA cases other tha n RASD. After the reclassification of 58 primary RA patients, the grou p was composed of 45 RAminiD and 13 RASD patients. The blast percentag e in the BM and the frequency of cytogenetic abnormalities observed in the RASD patients were intermediate between those in the RAminiD and RAEB patients. The analysis of survival curves revealed differences am ong the three groups; the RASD patients had lower survival probabiliti es than those of the RAminiD group, and significantly higher probabili ties than those of the RAEB group. (RAminiD vs RASD, P=0.06; RASD vs R AEB, P=0.004.) Our data indicate that in RA patients, RASD is a distin ct subset of RA with an unfavorable clinical outcome.