Comparable survival for pediatric acute myeloid leukemia with poor-risk cytogenetics following chemotherapy, matched related donor, or unrelated donor transplantation

Abstract

We sought to better define the role of hematopoietic cell transplantation (HCT) in first remission (CR1) for high-risk pediatric acute myeloid leukemia (AML). Outcomes were compared among patients aged less than 21 years with cytogenetically defined poor-risk AML treated with chemotherapy, matched related (MRD), or unrelated donor (URD) transplantation in CR1. Poor-risk cytogenetics was defined as monosomy 7/del7q, monosomy 5/del 5q, abnormalities of 3q, t(6;9)(p23;q34), or complex karyotype. Included are patients treated on Children's Oncology Group trials or reported to the Center for International Blood and Marrow Transplant Research from 1989 to 2006. Of the 233 patients, 123 received chemotherapy, 55 received MRD HCT, and 55 received URD HCT. The 5-year overall survival from the time of consolidation chemotherapy or transplant conditioning was similar: chemotherapy (43% ± 9%), MRD (46% ± 14%), or URD (50% ± 14%), P = 0.99. Similarly, multivariate analysis demonstrated no significant differences in survival [(reference group = chemotherapy); MRD HR 1.08, P = 0.76; URD HR 1.13, P = 0.67] despite lower relapse risk with URD HCT (HR = 0.43, P = 0.01). Our findings do not provide support for the preferential use of HCT over chemotherapy alone for children with cytogenetically defined poor-risk AML in CR1.