Clinical characteristics and outcomes according to age in lenalidomide-treated patients with RBC transfusion-dependent lower-risk MDS and del(5q)

Background: Particularly since the advent of lenalidomide, lower-risk myelodysplastic syndromes (MDS) patients with del(5q) have been the focus of many studies; however, the impact of age on disease characteristics and response to lenalidomide has not been analyzed. Methods: We assessed the effect of age on clinical characteristics and outcomes in 286 lenalidomide-treated MDS patients with del(5q) from two multicenter trials. Results: A total of 33.9, 34.3, and 31.8% patients were aged <65 years, ≥65 to <75 years, and ≥75 years, respectively. Age <65 years was associated with less favorable International Prognostic Scoring System (IPSS) risk and additional cytopenias at baseline versus older age groups, significantly lower cytogenetic response rates (p = 0.022 vs. ≥65 to <75 years; p = 0.047 vs. ≥75 years), and higher rates of acute myeloid leukemia (AML) progression (Gray's test, p = 0.013). Lenalidomide was equally well tolerated across age groups, producing consistently high rates of red blood cell transfusion independence ≥26 weeks. Conclusions: Baseline disease characteristics and AML progression appear to be more severe in younger lower-risk MDS patients with del(5q), whereas older age does not seem to compromise the response to lenalidomide. Trial registration: ClinicalTrials.gov NCT00065156 and NCT00179621