How I Treat: MRD testing to personalize allogeneic HCT for adults with AML.

Allogeneic hematopoietic cell transplantation (allo-HCT) is long established as the only curative option for many patients with acute myeloid leukemia (AML). Recent evidence demonstrates that measurable residual disease (MRD) testing, known to help stratify patients with AML in remission based on their risk for post-HCT relapse and mortality, can provide opportunities for patient-specific allo-HCT personalization. This includes patient selection for transplantation, guiding conditioning regimen intensity, surveillance for early identification of relapse during post-transplant remission, and, in some cases, selecting patients predicted to benefit from post-transplant maintenance or pre-emptive therapy. Just as therapy for AML is not yet perfected, MRD testing for AML currently still has many caveats but is emerging as a useful tool in specific contexts for the clinical management of those undergoing allo-HCT. As with all emerging technologies, physicians continue to face uncertainty regarding how to appropriately interpret or intervene upon such results. As we move forward, it will be important to distinguish promising translational research claims and theoretical aspirations from the practical testing realities in order to provide robust, reproducible, and actionable results to better guide therapeutic decisions. In four representative cases, we describe how we currently use MRD testing for adult patients with AML undergoing allo-HCT.