Persistence of minimal residual disease assessed by multiparameter flow cytometry is highly prognostic in younger patients with acute myeloid leukemia

BACKGROUND Predicting outcomes for patients with acute myeloid leukemia (AML) on the basis of pretreatment predictors has been the cornerstone of management. Posttreatment prognostic factors are increasingly being evaluated. METHODS Among 280 younger patients who were treated with intermediate-dose cytarabine (total ≥ 5 g/m2) and idarubicin-based induction chemotherapy and achieved remission, 186 were assessed for minimal residual disease (MRD) with an 8-color multiparameter flow cytometry panel performed on bone marrow specimens with a sensitivity of 0.1% or higher. RESULTS One hundred sixty-six patients had samples available 1 to 2 months after induction at the time of complete remission (CR), and 79% became negative for MRD, with an MRD-negative status associated with an improvement in relapse-free survival (RFS; P = .0002) and overall survival (OS; P = .0002). One hundred sixteen were evaluated for their MRD status during consolidation, and 86% were negative, with an MRD-negative status associated with a significant improvement in RFS (P