Children with acute myelogenous leukemia (AML) have a high risk of infectious complications that might be reduced by prophylactic granulocyte colony-stimulating factor (G-CSF). However, G-CSF could induce AML blast proliferation. The prospective randomized trial AML-BFM 98 investigated the impact of G-CSF on hematopoetic recovery and infectious complications (primary endpoints) and on outcome (secondary endpoint) in children (aged 0-18 years) with de novo AML. Patients with more than 5% blasts in day-15 bone marrow or with FAB M3 were not included. Between 1998 and 2003, 161 children with AML were randomized to receive G-CSF after inductions 1 and 2, whereas 156 patients were assigned to the control group. Time of neutropenia after inductions 1 and 2 was significantly shorter in the G-CSF group (23 vs 18 days and 16 vs 11 days; P=.02 and=.001, respectively). G-CSF did not decrease the incidence of febrile neutropenia (72 and 36 patients vs 78 and 37 patients, respectively), microbiologically documented infections (27 and 25 patients vs 36 and 19 patients, respectively) and infection-associated mortality (5 vs 2 patients). Both groups had similar 5-year event-free survival (EFS; 59%+/-4% vs 58%+/-4%). Since G-CSF does not influence the risk of infectious complications or outcome in children undergoing therapy for AML, one cannot advocate the routine use of G-CSF in this patient group.