Clinical prognostic factors for survival and risk of progression to acute myeloid leukemia in patients with myelodysplastic syndromes with < 10% marrow blasts and non-unfavorable cytogenetic categories

Abstract

Prognosis of myelodysplastic syndromes (MDS) is an area of ongoing interest. Identification of patients with poor outcome in the categories of lower risk disease is critical. In this study, we classify a cohort of 332 lower risk MDS into 3 groups with differences in survival and risk for leukemic progression that could drive treatment approaches to improve prognosis in a fraction of these patients.

Background: Prognosis of MDS and particularly in patients categorized as lower risk (< 10% blasts or low and intermediate-1 International Prognostic Scoring System [IPSS]) is very heterogeneous and includes patients with very different outcomes with current scoring systems. Recently, a new cytogenetic classification has been proposed for the revised IPSS in predicting the outcome for MDS.

Patients and methods: To evaluate the prognostic significance of multiple variables for survival and risk of progression to acute myeloid leukemia, we analyzed baseline characteristics of 332 lower risk MDS patients within the lower risk cytogenetic categories by IPSS and the recent proposal for the new cytogenetic classification.

Results: In multivariate analysis, severity of cytopenias, age > 60 years, bone marrow blasts (5%-9%) and transfusion dependency significantly influenced outcome. The combination of these variables allowed development of a model which categorizes patients in 3 different groups with median survival of 95, 44, and 13 months for groups 1, 2, and 3, respectively (P < .001). In addition, this score also stratified patients for their risk for leukemic progression, estimated at 2 years in 3.1%, 7.6%, and 21.3% for each group (P = .024).

Conclusion: Although karyotype remains the main prognostic factor in MDS, the current study identifies clinical parameters predicting outcome among patients with the better cytogenetic profile. Degree of cytopenias, blasts 5%-9% and transfusion dependence might identify a subset of patients within the nonadverse karyotype, in which early or more aggressive approaches could possibly be required to improve survival or prevent disease progression.