Evaluating Multiple Myeloma Survival Rates by Race, Ethnicity, and Rural-Urban Location

Both overall survival and myeloma-specific survival have improved over the last 4 decades for all racial groups, regardless of urban or rural living location, according to an abstract presented at the 65th American Society of Hematology Annual Meeting and Exhibition.¹

In a cross-sectional study, researchers from the Levine Cancer Institute in Charlotte, North Carolina, and the Emory University School of Medicine in Atlanta, Georgia, utilized SEER data from 1975 to 2019 to evaluate how 5-year multiple myeloma survival rates differ across rural and urban settings, as well as across a diverse sample of individuals of different races.

Investigators determined rural-urban designation using the 2013 Rural Urban Continuum Codes, while race and ethnicity data were coded by SEER. Overall survival was defined as time from diagnosis to death from any cause; myeloma-specific survival was defined as time from diagnoses to myeloma-related death, and deaths due to non-myeloma causes were censored at date of death.

Between 1975 and 2019, more than 40,000 multiple myeloma cases were identified, with 55.9% of those cases in individuals aged between 60 and 79 years. Within the cohort, 46.2% of patients were women, 7% were Hispanic, 15.1% were non-Hispanic Black, and 77.9% were non-Hispanic White. A majority—84.7% of patients lived in urban settings.

Patients living in rural settings were more likely to be non-Hispanic White (92.2%), while “very few”—only 1.3%—of non-Hispanic Black patients lived in rural counties.

From 1975 to 2019, 5-year overall and myeloma-specific survival rates increased in both urban and rural areas: from 28.1% to 62.8% for patients in urban areas, and from 26.5% to 56% for those living in rural settings. Results of a multivariable model evaluating data available after January 1, 1990, indicated that a younger age, an urban home address, a later year of diagnosis, and a non-Hispanic Black race were “significantly associated with superior myeloma-specific survival,” the researchers noted. Non-Hispanic Black patients also demonstrated “significantly improved” myeloma-specific survival compared with non-Hispanic White patients (HR, 0.928). No significant relationship between rurality and race was noted.

Results of a multivariable model examining overall survival found that younger age, later year of diagnosis, female sex, and an urban home address were all associated with superior overall survival—with race or ethnicity no longer a significant factor.

“Over a [more than] 4 decade study period, 5-year overall survival and myeloma specific survival rate increased in all racial groups regardless of rural-urban location,” the researchers concluded. “Although the annual percent change for myeloma-specific survival was greater for [non-Hispanic White] than [non-Hispanic Black] patients, the latter exhibited better outcomes…even after adjusting for all other factors.”

“We plan to expand our analyses to include SEER-Medicare linked databases to understand if differences in treatment variables, demographics, and socioeconomic status can explain the disparities in survival,” they added.

Reference

1. Testamark S, Verbyla A, Robinson M, Voorhees PM, Bhutani M. Rural-urban and racial trends in survival of patients with multiple myeloma: 1975-2019 Surveillance, Epidemiology, and End Results (SEER) analysis. Presented at: 65th American Society of Hematology Annual Meeting and Exhibition; December 9-12, 2023; San Diego, CA. Abstract 1977.