2026 update on MM: Diagnosis, risk stratification, and management

A 2026 update on the diagnosis, risk stratification, and management of multiple myeloma (MM) was published by Rajkumar in the American Journal of Hematology.

Key data: The revised International Myeloma Working Group (IMWG) criteria require ≥10% clonal bone marrow plasma cells or a biopsy-proven plasmacytoma plus ≥1 myeloma-defining event (MDE) for the diagnosis of MM. The International Myeloma Society (IMS)/IMWG definition of high-risk MM includes: deletion 17p [del(17p)] and/or p53 mutation; biallelic del(1p); translocation (4;14) [t(4;14)], t(14;16), or t(14;20) plus gain(1q) or del(1p); or gain(1q) plus del(1p). For newly diagnosed (ND) MM, initial therapy generally consists of a quadruplet regimen of daratumumab or isatuximab plus bortezomib + lenalidomide + dexamethasone (VRd), with autologous stem-cell transplantation (ASCT) considered in eligible patients. Delayed ASCT is an option for selected standard-risk patients, while triplet regimens are recommended for frail patients. Standard maintenance is lenalidomide plus daratumumab or isatuximab; bortezomib plus lenalidomide is an alternative for high-risk MM. Treatment options for relapsed disease include chimeric antigen receptor (CAR) T-cell, bispecific antibodies (BsAbs), triplet regimens, and belantamab mafodotin. Daratumumab for 3 years should be considered in patients with high-risk smoldering MM.

Key learning: The 2026 update outlines current approaches to the diagnosis, risk stratification, and management of MM, with treatment selection based on disease risk, patient fitness, transplant eligibility, and treatment history.