Busulfan/melphalan is an effective and well tolerated conditioning regimen for pediatric AML and MDS patients receiving a matched sibling BMT
Year: 2006
Type: article
Abstract: Background: Allogeneic transplant results in the best outcomes for pediatric patients with myeloid malignancies and matched sibling donors (MRD). Improvements in supportive care, prophylaxis of infections, and treatment of GvHD has decreased non-relapse related morbidity and mortality. Conditioning regimens without TBI would be expected to result in less long term toxicity, but may not be as effective in preventing relapse. We report results of allogeneic MRD transplantation after a busulfan (Bu) and melphalan (Mel) conditioning regimen for a group of 36 pediatric patients transplanted at a single center. Methods: From 11/93–9/05, 36 children with AML or MDS received Bu (1 mg/kg/dose × 16 doses) and Mel (60 mg/m2 daily × 3) followed by a 5/6 or 6/6 HLA MRD BMT. GvHD prophylaxis was CyA and MTX. Twenty-nine patients had AML: 19 in CR1; 3 in CR2; 7 were either induction failures or were in relapse at the time of transplant. Seven patients had MDS: 5 were de novo patients; 1 was a patient constitutionally mosaic for trisomy 8, and 1 was a patient with monosomy 7 following treatment for ALL. Patients were evaluated for engraftment, toxicity, relapse, and overall survival. Results: All donors were siblings, either HLA identical (n = 34) or a 5/6 match caused by a crossover event (n = 2). All patients successfully engrafted with a median time to engraftment (ANC > 500/uL) of +14 days. Five patients experienced grade II acute graft-versus-host disease (aGvHD) and 3 experienced chronic GvHD (1 limited and 2 extensive). No patient died of infection, 1 died of pulmonary toxicity, 1 patient survived an intracranial hemorrhage with neurological sequela, and 1 patient survived a diffuse pulmonary alveolar hemorrhage. Seven AML patients relapsed (6 in marrow and one isolated CNS chloroma) yielding a 75% disease free survival and an 80% overall survival. All of the marrow relapsed patients subsequently died (4 were CR1 and 2 were in relapse at the time of BMT). All 7 MDS patients survive disease free. With a median follow-up of 6 years the disease free and overall survival are both 29/36 (81%). Non-relapse mortality was 1 out of 36 (3%). Conclusions: Bu/Mel is an effective, well tolerated conditioning regimen for pediatric patients with AML or MDS. Leukemic relapse, occurring in 25% of the AML patients, remains the main cause of treatment failure. Additional trials are indicated to verify these results at other pediatric transplant centers.
Institution: Duke Medical Center
Language: English
Subfield: Hematology
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $3,650
OpenAlex ID: W2020126419