We explore the predictive role of 2014-updated International Myeloma Working Group (IMWG) diagnostic criteria and of some of currently available risk models for progression to symptomatic myeloma when applied in our unselected population of 75 smoldering multiple myeloma (SMM) patients observed between 2000 and 2015. Risk scores including routinely used clinical parameters such as bone marrow plasmacell infiltration rate, immunoparesis, serum monoclonal component (sMC) value, and altered free light chain ratio (FLCr), were clinically useful to identify SMM patients at higher risk of progression. Time to myeloma progression in our ultra-high risk SMM according to IMWG diagnostic update criteria was very short (12.4 months). Our analysis identified as independent reliable predictors of progression altered FLCr as well as increasing plasma cell infiltration which are part of most commonly applied risk models. Waiting for new scoring systems, bone marrow evaluation and complete laboratory screening are still milestones for SMM management.
Keywords: Smoldering myeloma; bone marrow plasma cells; free light chains; scoring systems.