Early hematopoietic stem cell transplant is associated with favorable outcomes in children with MDS

Background: Although hematopoietic stem cell transplantation (HSCT) is the treatment of choice for childhood myelodysplastic syndrome (MDS), there is no consensus regarding patient or disease characteristics that predict outcomes. Procedure: We reviewed 37 consecutive pediatric MDS patients who received myeloablative HSCT between 1990 and 2010 at a single center. Results: Twenty had primary MDS and 17 had secondary MDS. Diagnostic cytogenetics included monosomy 7 (n=21), trisomy 8 (n=7) or normal/other (n=8). According to the modified WHO MDS classification, thirty had refractory cytopenia and seven had refractory anemia with excess blasts. IPSS scores were: low risk (n=1), intermediate-1 (n=15), and intermediate-2 (n=21). OS and DFS at 10 years in the entire cohort was 53% and 45%. Relapse at 10 years was 26% and 1 year TRM was 25%. In multivariate analysis, factors associated with improved 3 years DFS were not receiving pre-HSCT chemotherapy (RR=0.30, 95% CI 0.10-0.88; P=0.03) and a shorter interval (<140 days) from time of diagnosis to transplant (RR=0.27, 95% CI 0.09-0.80; P=0.02). Three years DFS in patients who did not receive pre-HSCT chemotherapy and those who had a shorter interval to transplant (n=16) was 80%. Conclusion: These results suggest that children with MDS should be referred for allogeneic HSCT soon after diagnosis and that pre-HSCT chemotherapy does not appear to improve outcomes.