Favorable outcome in infants with AML after intensive first- nd second-line treatment: an AML-BFM study group report

Infants <1 year of age have a high prevalence of prognostically unfavorable leukemias and a presumed susceptibility to treatment-related toxicities. A total of 125 infants with acute myeloid leukemia (AML) were treated in studies AML-BFM-98 (n = 59) and -2004 (n = 66). Treatment regimens of both studies were comparable, consisting of intensive induction followed by four courses (mainly high-dose cytarabine and anthracyclines). Allogeneic-hematopoietic stem-cell-transplantation (allo-HSCT) in 1st remission was optional for high-risk (HR) patients. Most infants (120/125 = 96%) were HR patients according to morphological, cytogenetic/molecular genetic and response criteria. Five-year overall survival was 66 +/- 4%, and improved from 61 +/- 6% in study-98 to 75 +/- 6% in study-2004 (P-logrank 0.14) and event-free survival rates were 44 +/- 6% and 51 +/- 6% (P-logrank 0.66), respectively. Results in HR infants were similar to those of older HR children (1-<2- or 2-<10-year olds, P-logrank 0.90 for survival). Survival rates of HSCT in 1st remission, initial partial response and after relapse were high (13/14, 2/8 and 20/30 patients, respectively). The latter contributes to excellent 5-year survival after relapse (50 +/- 8%). Despite more severe infections and pulmonary toxicities in infants, treatment-related death rate was identical to that of older children (3%). Our data indicate that intensive frontline and relapse AML treatment is feasible in infants, toxicities are manageable, and outcome is favorable. Leukemia (2012) 26, 654-661; doi:10.1038/leu.2011.267; published online 4 October 2011