Soluble B-cell maturation antigen in multiple myeloma.

B-cell maturation antigen (BCMA) has emerged as a promising immunotherapeutic target in multiple myeloma (MM) management, with the successive approval of antibody-drug conjugates, bispecific antibodies, and chimeric antigen receptor T-cell therapies directed to this membrane receptor. Soluble BCMA (sBCMA), a truncated version produced through gamma-secretase cleavage, can be quantified in serum/plasma samples from patients with MM via electrochemiluminescence, fluorescence, or enzyme-linked immunosorbent assays, as well as through mass spectrometry-based proteomics. Besides its short serum half-life and independence from kidney function, sBCMA represents a reliable and convenient tool for MM monitoring in patients with nonsecretory or oligosecretory disease. Numerous studies have suggested a potential utility of this bioanalyte in the risk stratification of premalignant plasma cell disorders, diagnosis and prognostication of MM, and response evaluation following anti-myeloma therapies. In short, sBCMA might be the "Swiss army knife" of MM laboratory testing, but is it ready for prime time?

Revisiting the role of alkylating agents in multiple myeloma: Up-to-date evidence and future perspectives.

From the 1960s to the early 2000s, alkylating agents (e.g., melphalan, cyclophosphamide, and bendamustine) remained a key component of standard therapy for newly-diagnosed or relapsed/refractory multiple myeloma (MM). Later on, their associated toxicities (including second primary malignancies) and the unprecedented efficacy of novel therapies have led clinicians to increasingly consider alkylator-free approaches. Meanwhile, new alkylating agents (e.g., melflufen) and new applications of old alkylators (e.g., lymphodepletion before chimeric antigen receptor T-cell [CAR-T] therapy) have emerged in recent years. Given the expanding use of antigen-directed modalities (e.g., monoclonal antibodies, bispecific antibodies, and CAR-T therapy), this review explores the current and future role of alkylating agents in different treatment settings (e.g., induction, consolidation, stem cell mobilization, pre-transplant conditioning, salvage, bridging, and lymphodepleting chemotherapy) to ellucidate the role of alkylator-based regimens in modern-day MM management.