Utility of flow cytometry studies in the management of patients with multiple myeloma

Abstract

Purpose of review: Although the input of multiparameter flow cytometry (MFC) into the clinical management of multiple myeloma (MM) patients has faced some reluctance, continuously growing evidence supports the utility of MFC in this disease. Recent findings: MFC immunophenotyping of bone marrow and peripheral blood plasma cells affords cost-effective assessment of clonality, and provides prognostic information on the risk of progression in smoldering MM, and the identification of active MM patients with dismal outcome (e.g.: high numbers of circulating tumor cells) or long-term survival despite sub-optimal responses through the characterization of MGUS-like phenotypes. Extensive data indicates that MRD monitoring can be used as biomarker to evaluate treatment efficacy and act as surrogate for survival. The time has come to address within clinical trials, the exact role of baseline risk factors and MRD monitoring for tailored therapy in MM, which implies systematic usage of highly sensitive cost-effective, readily available and standardized MRD techniques such as MFC. Summary: Next-generation MFC should be considered mandatory in the routine evaluation of MM patients both at diagnosis and after therapy, and represents an attractive technique to integrate with high-throughput DNA and RNA-seq methods to help understanding the mechanisms behind dissemination and chemoresistance of MM.