@article{3103771,
    title = "International Myeloma Working Group risk stratification model for smoldering multiple myeloma (SMM)",
    author = "Mateos, M.-V. and Kumar, S. and Dimopoulos, M.A. and González-Calle, V. and Kastritis, E. and Hajek, R. and De Larrea, C.F. and Morgan, G.J. and Merlini, G. and Goldschmidt, H. and Geraldes, C. and Gozzetti, A. and Kyriakou, C. and Garderet, L. and Hansson, M. and Zamagni, E. and Fantl, D. and Leleu, X. and Kim, B.-S. and Esteves, G. and Ludwig, H. and Usmani, S. and Min, C.-K. and Qi, M. and Ukropec, J. and Weiss, B.M. and Rajkumar, S.V. and Durie, B.G.M. and San-Miguel, J.",
    journal = "Blood cancer journal",
    year = "2020",
    volume = "10",
    number = "10",
    publisher = "Springer Nature BV",
    doi = "10.1038/s41408-020-00366-3",
    keywords = "beta 2 microglobulin;  biological marker;  creatinine;  hemoglobin;  immunoglobulin A;  immunoglobulin D;  immunoglobulin G;  immunoglobulin M;  M protein;  immunoglobulin light chain;  multiple myeloma M-proteins;  paraprotein;  tumor marker, adult;  aged;  albumin blood level;  amyloidosis;  analysis;  Article;  cancer growth;  cell infiltration;  clinical practice;  clinical research;  cohort analysis;  creatinine blood level;  cytogenetics;  female;  fluorescence in situ hybridization;  follow up;  hemoglobin blood level;  human;  light chain;  major clinical study;  male;  medical record review;  plasma cell;  protein blood level;  random forest;  retrospective study;  risk factor;  smoldering multiple myeloma;  trisomy 13;  biological model;  blood;  clinical trial;  disease exacerbation;  metabolism;  middle aged;  multicenter study;  multiple myeloma, Aged;  Biomarkers, Tumor;  Disease Progression;  Female;  Follow-Up Studies;  Humans;  Immunoglobulin Light Chains;  Male;  Middle Aged;  Models, Biological;  Multiple Myeloma;  Myeloma Proteins;  Risk Factors",
    abstract = "Smoldering multiple myeloma (SMM) is an asymptomatic precursor state of multiple myeloma (MM). Recently, MM was redefined to include biomarkers predicting a high risk of progression from SMM, thus necessitating a redefinition of SMM and its risk stratification. We assembled a large cohort of SMM patients meeting the revised IMWG criteria to develop a new risk stratification system. We included 1996 patients, and using stepwise selection and multivariable analysis, we identified three independent factors predicting progression risk at 2 years: serum M-protein >2 g/dL (HR: 2.1), involved to uninvolved free light-chain ratio >20 (HR: 2.7), and marrow plasma cell infiltration >20% (HR: 2.4). This translates into 3 categories with increasing 2-year progression risk: 6% for low risk (38%; no risk factors, HR: 1); 18% for intermediate risk (33%; 1 factor; HR: 3.0), and 44% for high risk (29%; 2–3 factors). Addition of cytogenetic abnormalities (t(4;14), t(14;16), +1q, and/or del13q) allowed separation into 4 groups (low risk with 0, low intermediate risk with 1, intermediate risk with 2, and high risk with ≥3 risk factors) with 6, 23, 46, and 63% risk of progression in 2 years, respectively. The 2/20/20 risk stratification model can be easily implemented to identify high-risk SMM for clinical research and routine practice and will be widely applicable. © 2020, The Author(s)."
}