Flow cytometric and molecular MRD in AML: current methods, clinical applications and challenges

Measurable residual disease (MRD) in acute myeloid leukemia (AML) provides prognostic information beyond molecular risk classification at diagnosis, facilitating personalized treatment strategies and improved patient outcomes. This review focuses on the clinical implementation of MRD in patients in remission after induction therapy. We discuss the three primary methods for MRD detection, including multiparameter flow cytometry (MFC), polymerase chain reaction (PCR), and next-generation sequencing (NGS), highlighting their respective prognostic value, strengths, and limitations. We review the clinical application of MRD in guiding consolidation treatment, particularly regarding (de)-intensification of allogeneic stem cell transplantation. Additionally, we address evidence on the utility of MRD in selecting conditioning intensity, stem cell source, and additional pre-consolidation treatment. Currently, the main challenge of MRD is methodological standardization and harmonization across laboratories, which is being addressed by several international working parties. In this context, the value of combining MRD methods and leveraging their respective strengths should be further evaluated.