email article In 2014, the International Myeloma Working Group (IMWG) updated the diagnostic criteria for multiple myeloma – a change that has had a profound effect on the concept of early treatment of patients with smoldering multiple myeloma. The diagnosis of multiple myeloma traditionally required the presence of end-organ damage known as the CRAB criteria (increased calcium level, renal dysfunction, anemia, and destructive bone lesions). The IMWG update added three biomarkers that can be used to diagnose multiple myeloma in patients who do not have CRAB features: Clonal bone marrow plasma cells of 60% or more Serum free light chain (FLC) ratio of 100 or greater, involved FLC level is 100 mg/L or higher