Impact of Age on Transfusion Independence Response, Survival, and Transformation to Acute Myeloid Leukemia in Patients with Deletion 5q: A Sub-Analysis of the MDS-003 Study

Introduction: Recent data have demonstrated that lenalidomide reduced transfusion requirements and reversed cytologic and cytogenetic abnormalities in patients who have myelodysplastic syndrome (MDS) with the chromosome 5q31 deletion (List et al NEJM 2006). Previous studies have demonstrated that age may impact on survival rates in cancer patients, but the impact of age on patients treated with lenalidomide for deletion 5q [del(5q)] MDS has not been investigated. This sub-analysis investigated the impact of age on transfusion independence (TI) response, survival, transformation to acute myeloid leukemia (AML), and cytopenias in patients with deletion 5q who were treated with lenalidomide.

Methods: Transfusion-dependent, Low/Int-1-risk patients with primary MDS and del(5q) with/without additional cytogenetic abnormalities were treated with lenalidomide 10 mg daily or for 21 days every 28 days. Patients were treated until disease progression, treatment failure, or treatment-limiting adverse events. For this analysis, patients were subdivided into two categories: ≤75 and >75 years of age. The relationship between age and TI response, survival, progression to AML, and cytopenias were analyzed.

Results: A total of 148 patients were included in the study: 103 patients aged ≤75 years and 45 patients aged >75 years (Table). The TI response was 68% for patients aged ≤75 years and 60% for patients aged >75 years (P=0.35). As expected, median survival was shorter for older patients (P=0.01). There was no difference in the progression to AML with 22% progressing for patients aged ≤75 years and 16% for patients aged >75 years (P=0.65). Cytopenias were reported in 84% and 76% of patients aged ≤75 and >75 years, respectively (p=0.42).

Conclusion: Patients aged >75 years had a similar TI response to patients aged ≤75 years of age. Survival was shorter as is to be expected in an older age group with a lower average life expectancy. There was no difference in the rate of progression to AML when compared with patients aged ≤75 years. The rates of cytopenias were not influenced by patient age.