Unrelated Donor Bone Marrow Transplantation for Myelodysplastic Syndrome in Children

We describe long-term disease-free survival (DFS) after unrelated donor bone marrow transplantation (BMT) for myelodysplastic syndrome (MDS) in 118 patients aged ≤18 years. Forty-six patients had refractory cytopenia (RC), 55 refractory anemia with excess blasts (RAEB), and 17 refractory anemia with excess blasts in transformation (RAEB-t). Transplant-related mortality was higher after mismatched BMT (relative risk [RR] 3.29, P = .002). Disease recurrence was more likely with advanced stages of MDS at the time of BMT: RAEB (RR 6.50, P = .01) or RAEB-t (RR 11.00, P = .004). Treatment failure (recurrent disease or death from any cause; inverse of DFS) occurred in 68 patients. Treatment failure was higher after mismatched BMT (RR 2.79, P = .001) and in those with RAEB-t (RR 2.38, P = .02). Secondary MDS or chemotherapy prior to BMT was not associated with recurrence or treatment failure. Similarly, cytogenetic abnormalities were not associated with transplant outcomes. Eight-year DFS for patients with RC after matched and mismatched unrelated donor BMT was 65% and 40%, respectively. Corresponding DFS for patients with RAEB and RAEB-t was 48% and 28%, respectively. When a matched adult unrelated donor is available, BMT should be offered as first-line therapy, and children with RC can be expected to have the best outcome.

Key Words: Pediatric myelodysplastic syndrome, Unrelated donor, Bone marrow transplantation