Gerrit Jan Schuurhuis, PhD, from the VU University Medical Center, Amsterdam, Netherlands, gives an overview of the use of minimal residual disease (MRD) to monitor acute myeloid leukemia (AML) and outlines its effectiveness as a prognostic factor at the International Symposium on Acute Leukemias (ISAL) 2017 in Munich, Germany. Minimal residual disease, namely the number of leukemia cells remaining after treatment, is now widely used after first therapy induction, and can be used to established if patients should be treated more intensively, such as with allogenic stem cell transplants. In addition, Dr Schuurhuis describes how minimal residual disease can be used in a post-consolidation setting, as monitoring MRD can predict upcoming relapses. This approach is now being used by a number of institutions. The next step, currently being addressed by European Leukemia Net, is to establish standardized approaches to assess MRD in AML, which is challenging due to the disease heterogeneity. Aspects to be harmonized include clinical issues as well as the assessment of MRD by flow cytometry and at a molecular level. Dr Schuurhuis explains that flow cytometry analysis of MRD can trace residual disease cells in 90% of AML patients, which cannot be matched by molecular analysis. However, due to the disease heterogeneity, flow cytometry parameters need to be optimized at diagnosis for each AML patient in order to allow MRD to be traced. This is much simpler for other types of leukemia which display less phenotypic variability.