Flicking the switch in myeloma MRD

In this issue of Blood, Paiva et al1 report that serial monitoring of measurable residual disease (MRD) during maintenance treatment of multiple myeloma (MM) captures dynamic conversion between negative (MRD-) and positive (MRD+) states and robustly anticipates progression-free survival (PFS). They show the feasibility of longer-term MRD monitoring and provide a rationale for trials that investigate intervention before frank relapse.