Measurable Residual Disease

The assessment of measurable residual disease (MRD) in the bone marrow is mandatory for the assessment of efficacy in clinical trials.[39-42] Does MRD testing outside of the trial setting yield meaningful clinical improvement in patient outcomes by informing selection or duration of therapy? Achievement of MRD negativity after induction therapy (with or without consolidation therapy) is associated with improved progression-free survival (PFS) and improved OS.[43-52] While MRD negativity may be useful for the design of clinical trials, there are no data suggesting that this interim marker improves outcomes by altering subsequent therapy. Similarly, there are no data to suggest that sustained MRD negativity can allow deintensification or discontinuation of maintenance therapy.[53,54] Using peripheral blood to assess for MRD appears feasible with next-generation flow and mass spectroscopy. This approach is less-invasive than using bone marrow.[55]