Asymptomatic Incidence of Monoclonal Gammopathy of Undetermined Significance and Preclinical Duration to Myeloma Diagnosis: A Modeling Study.

Background Monoclonal gammopathy of undetermined significance (MGUS) is the premalignant condition of multiple myeloma (MM). Given a lack of population-based screening for MGUS and its asymptomatic nature, the epidemiology of MGUS remains unknown. This study estimated age- and race/ethnicity-specific MGUS incidence and preclinical duration from MGUS to MM in the United States. Methods A previously published modeling approach was used to calculate national MGUS incidence using estimates of MGUS prevalence, MM incidence, MM-specific and all-cause mortality, and population age distribution from the National Health and Nutrition Examination Survey, 1999-2004, and Surveillance, Epidemiology, and End Results, 2000-2021. The estimated MGUS prevalence was divided by MGUS incidence to obtain preclinical duration of MM. Results MGUS incidence for non-Hispanic white (NHW) populations was 52, 86, 142, and 181 and for non-Hispanic black (NHB) population was 110, 212, 392, and 570 per 100,000 person-years at ages 50, 60, 70, and 80, respectively. The average preclinical duration was 20.5 (95% confidence interval, CI: 16.5, 26.1) years for the NHW population and 14.2 (95% CI: 11.5, 17.6) years for the NHB population. The cumulative risk of developing MGUS in age 50-85 was 2.8% (95% CI: 1.7%, 4.2%) for the NHW population and 6.1% (95% CI: 3.8%, 10.0%) for the NHB population. Conclusion NHB populations had a higher MGUS incidence rate at all ages and a shorter preclinical duration of MM compared to their NHW counterparts. Impact This study provides insights into the epidemiology of MGUS and enhances our understanding of the natural history of MM.