Identification of novel cytogenetic markers with prognostic significance in a series of 968 patients with primary myelodysplastic syndromes.

BACKGROUND AND OBJECTIVES The main prognostic factors in myelodysplastic syndromes (MDS) are chromosomal abnormalities, the proportion of blasts in bone marrow and number and degree of cytopenias. A consensus-defined International Prognostic Scoring System (IPSS) for predicting outcome and planning therapy in MDS has been developed, but its prognostic value in a large and independent series remains unproven. Furthermore, the intermediate-risk cytogenetic subgroup defined by the IPSS includes a miscellaneous number of different single abnormalities of uncertain prognostic significance at present. The main aim of the present study was to identify chromosomal abnormalities with a previously unrecognized good or poor prognosis in order to find new cytogenetic markers with predictive value. DESIGN AND METHODS We report the cytogenetic findings in a series of 968 patients with primary MDS from the Spanish Cytogenetics Working Group, Grupo Cooperativo Español de Citogenética Hematológica (GCECGH). RESULTS In this series of 968 MDS patients, we found various cytogenetic aberrations with a new prognostic impact. Complex karyotype, -7/7q- and i(17q) had a poor prognosis; normal karyotype, loss of Y chromosome, deletion 11q, deletion 12p and deletion 20q as single alterations had a good prognosis. Intermediate prognosis aberrations were rearrangements of 3q21q26, trisomy 8, trisomy 9, translocations of 11q and del(17p). Finally, a new group of single or double cytogenetic abnormalities, most of which are considered rare cytogenetic events and are usually included in the intermediate category of the IPSS, showed a trend to poor prognosis. INTERPRETATION AND CONCLUSIONS This study suggests that some specific chromosomal abnormalities could be segregated from the IPSS intermediate-risk cytogenetic prognostic subgroup and included in the low risk or in the poor risk groups.