Transfusion dependence development and disease evolution in patients with MDS and del(5q) and without transfusion needs at diagnosis

Patients with isolated del(5q) and MDS are considered to have good prognosis as compared to other MDS subtypes. Most patients suffered of anemia and 50% of them required transfusions at diagnosis. It is known that for patients with MDS and del(5q) in transfusion dependence(TD), Lenalidomide is the first choice treatment. However, there are no data regarding natural evolution of anemia in patients diagnosed in MDS and del(5q) without TD, factors that may impact on the development of TD or disease outcome. In the present study we have performed a retrospective multicenter analysis on 83 patients with low-int 1 MDS and del(5q) without TD. During the study 61 patients became TD at a median of 1.7 years and only the Hb level 9g/dL was associated with poorer TFS (p=0.007) in the multivariate analysis. Among these 61 TD patients, 49 received treatment (19 Lenalidomide). Median follow up was 48 months, estimated OS at 2 and 5 year was 92% and 50% respectively. In the multivariate analysis for OS, platelets <100,000mm^-3 and Lenalidomide treatment retained the statistical significant impact. LFS at 2 and 5 years was 86% and 73% respectively, and median time to sAML was 8.16 years (CI 95%: 6.05-10.27). In the multivariate analysis only thrombocytopenia retained statistical significance. In summary, this retrospective study show that level of Hb is an important parameter in order to determine the time until TD, it should be also stressed the importance of an early treatment in order to prevent TD development and shorter survival.