The incidence of multiple myeloma is nearly 2-fold higher in African Americans than in whites. There are also differences in overall survival between the 2 races. This difference is not completely explained by racial disparities, and researchers postulate that some of the differences may be attributable to genetic variations between the 2 groups.
Using data from the National Cancer Institute, researchers examined differences in the incidence, mortality, and survival of 68,701 white, 16,364 black, and 4802 other patients with MM who were classified by race, sex, and age, from 1973 to 2012. Age-adjusted incidence and mortality rates, regression analysis, and survival curves were calculated by race. Median age at diagnosis was 66 years for African Americans and 71 years for whites (P <.01).
The age-adjusted incidence rates per 100,000 population for African Americans (11.9; P <.05) were more than double the corresponding rates for whites (5.1). African Americans present with myeloma at a lower age compared with whites, and this difference was seen during the course of the study.
Although 5-year relative survival is improving for all races and sexes, the survival analysis showed that African American race is an independent factor for improved survival (hazard ratio, 0.884; P <.0001). Further population-based studies focused on how exploring the underlying biologic mechanisms of disease may explain unanswered questions such as higher incidence rates and better overall survival among African American patients.