A significant method for defining profound responses in multiple myeloma (MM) is next-generation flow cytometry (NGF), which measures minimum residual disease (MRD). However, the benefits of integrating NGF with functional imaging and its usefulness for MRD-based consolidation methods in everyday clinical practice were not well understood. In the study, researchers described their investigations into the problems, including 102 patients with relapsed/refractory MM (n=45) and newly diagnosed MM (n=57).

Either diffusion-weighted magnetic resonance imaging or positron emission tomography was used for imaging. A total of 45% of patients attained MRD-negativity on both NGF and imaging (double-negativity), whereas 8% and 40% of patients, respectively, were negative on NGF or imaging. Consequently, imaging was the sole method used to find residual illness in a small percentage of patients.

When compared to freshly diagnosed MM, severely pretreated illness (4 or more prior lines) had a higher prevalence of imaging-positivity despite NGF negative (P<0.01). In the 29 patients with MRD-triggered consolidation, MRD conversion occurred in 51% of cases and enhanced serological response in 21% of cases. When compared to normal therapy, MRD-triggered consolidation resulted in a better progression-free survival (PFS) rate (P=0.04).

In summary, the research demonstrated the value of combining NGF with imaging, especially in patients with MM who have received a lot of prior therapy, and suggested that MRD-based consolidation may enhance PFS.

Reference: onlinelibrary.wiley.com/doi/10.1111/bjh.18249