Multiple myeloma accounts for approximately 10% of hematologic malignancies. The diagnosis requires ā„10% clonal bone marrow plasma cells or a biopsy proven plasmacytomaĀ plusĀ evidence of one or more multiple myeloma defining events: CRAB (hypercalcemia, renal failure, anemia, or lytic bone lesions) features felt related to the plasma cell disorder, bone marrow clonal plasmacytosis ā„60%, serum involved/uninvolved free light chain (FLC) ratio ā„100 (provided involved FLC is ā„100 mg/L), or >1 focal lesion on magnetic resonance imaging. Patients with del(17p), t(14;16), and t(14;20) have highārisk multiple myeloma. Patients with t(4;14) translocation and gain(1q) have intermediateārisk. All others are considered standardārisk. Initial treatment consists of bortezomib, lenalidomide, dexamethasone (VRd). In highārisk patients, carfilzomib, lenalidomide, dexamethasone (KRd) is an alternative to VRd. In eligible patients, initial therapy is given for approximately 3ā4 cycles followed by autologous stem cell transplantation (ASCT). Standard risk patients can opt for delayed ASCT at first relapse. Patients not candidates for transplant are treated with VRd for approximately 8ā12 cycles followed by lenalidomide or lenalidomide plus dexamethasone. After ASCT, lenalidomide maintenance is recommended for standard risk patients, while maintenance with a bortezomibābased regimen is needed for patients with intermediate or highārisk disease. Most patients require a triplet regimen at relapse, with the choice of regimen varying with each successive relapse. Aggressive relapse with extramedullary plasmacytomas or plasma cell leukemia may require anthracycline containing combination chemotherapy regimens.
Update on diagnosis, riskāstratification and management
