Outcome disparities in multiple myeloma: a SEER-based comparative analysis of ethnic subgroups

Studies of ethnic disparities in malignancies have revealed variation in clinical outcomes. In multiple myeloma (MM), previous literature has focused only on patients of Caucasian and African-American (AA) descent. We present a Surveillance Epidemiology and End Results (SEER)-based outcome analysis of MM patients from a broader range of ethnicities, representing current United States demographics. The SEER 17 Registry data was utilized to analyse adult MM patients diagnosed since 1992 (n = 37,963), as patients of other ethnicities were not well represented prior to that. Overall survival (OS) and myeloma-specific survival (MSS) were compared across different ethnicities stratified by year of diagnosis, registry identification, age, sex and marital-status. Hispanics had the youngest median age at diagnosis (65 years) and Whites had the oldest (71 years) (P < 0·001). Increased age at diagnosis was an independent predictor of decreased OS and MSS. Asians had the best median OS (2·7 years) and MSS (4·1 years), while Hispanics had the worst median OS (2·4 years). These trends were more pronounced in patients ≥ 75 years. Cumulative survival benefit over successive years was largest among Whites (1·3 years) and smallest among Asians (0·5 years). These disparities may be secondary to multifactorial causes that need to be explored and should be considered for optimal triaging of healthcare resources.