Outcome of allogeneic stem cell transplantation with a conditioning regimen of busulfan, cyclophosphamide and low-dose etoposide for children with myelodysplastic syndrome

Abstract

Allogeneic stem cell transplantation (SCT) offers the best chance of cure and long-term survival for children with myelodysplastic syndromes (MDS). Retrospective analysis of pediatric patients with primary MDS treated with allogeneic SCT at a single institution treated between January 1993 and December 2008. Of 16 consecutive children who received allogeneic SCT for treatment of MDS in our center, 14 patients met the criteria of MDS according WHO I and II criteria. The median age was 4.8 years (range, 1-14 years) and 64% were male. The median time from diagnosis to transplant was 6 months. MDS stage was refractory cytopenia (RC) in 9, refractory anemia with excess blasts (RAEB) in 5. Monosomy 7 was present in 35% of the patients. The majority of patients (11/14) were conditioned with a busulfan-based myeloablative (MA) regimen with addition of low-dose of etoposide (30 mg/kg). All but one received a bone marrow graft. Nine patients achieved complete remission (CR), and seven remain alive. At a median follow-up of 3 years (range, 2-14 years) the OS and EFS was 57% (95%CI, 0.28-0.78). Cumulative EFS at 10 years was 43% (95% CI, 0.14-0.70). Relapse-related mortality was 21.4%; nonrelapse mortality (NRM) was 28.57%. All the survivors had etoposide in their conditioning regimen. Patients younger than 10 years had better survival (P=.001). Children with MDS achieve encouraging OS and EFS following allogeneic SCT. A busulfan-based regimen with a lower dose of etoposide is an effective and less toxic regimen. The outcomes are best in younger patients.