Age, Blasts, Performance Status and Lenalidomide Therapy Influence the Outcome of Myelodysplastic Syndrome With Isolated Del(5q): A Study of 58 South American Patients

This study analyzed the overall survival (OS) of patients with Myelodysplastic Syndrome (MDS) with isolated deletion 5q in South America. Age >75 years, ECOG >= 2 and Bone marrow (BM) blasts >2% at diagnosis is independently associated with worse OS. Lenalidomide treatment is the only factor that improves the OS. Background: Myelodysplastic Syndrome (MDS) with isolated deletion 5q is associated with a low risk to leukemic evolution and long overall survival (OS); it comprises 3%-4.5% of MDS cases in Latin America classified according to the World Health Organization 2008. This study aims to describe clinical, laboratory and the outcome of patients according to the newest World Health Organization 2016 proposal. Methods: We retrospectively reviewed patients from four Brazilian (BR) and four Argentinean (AR) centers diagnosed between 1999 and 2019. Results: The 58 patients (16-AR and 42-BR) presented a median age of 67 (IQR 61-75) years old, women predominance (70.7%) and transfusion dependency (62.5%) at diagnosis. Median hemoglobin level was 8.1g/dL, 27.5% and 44.4% presented thrombocytosis and neutropenia, respectively. Bone marrow (BM) was predominantly hypercellular (43.1%) with 66% showing dysplasia >1 lineage and 37.9% with >2% of blasts. Deletion 5q was mostly isolated (79.3%) and a variety of abnormalities were observed in remaining cases. Most patients were treated with erythropoietin-stimulating agents (ESA), 18 with lenalidomide and 15 with thalidomide. Median follow-up was 7.6 years, with a median OS of 3.5 years and an 8-years leukemic evolution rate of 18.4%. Multivariate analysis showed that age >75 years (HR 2.19), ECOG =2 (HR 5.76), BM blasts >2% (HR 2.92) and lenalidomide treatment (HR 0.25) independently influenced the OS. Conclusion: Older age, worse performance status and higher percentage of blasts, that can be easily assessed, were associated to a worse prognosis. Also, our results corroborate the protective influence of lenalidomide in terms of OS in this South American series. (C) 2021 Elsevier Inc. All rights reserved.