Among U.S. adults diagnosed with multiple myeloma by age 40 years, 5-year and 10-year survival improved significantly (P less than .0001) for non-Hispanic blacks and whites, but not for Hispanics (5-year survival, P = .08; 10-year survival, P = .13), Abdel-Ghani Azzouqa, MD, and colleagues reported in a poster at the annual meeting of the American Society of Hematology.
Other population-based studies have uncovered racial and ethnic disparities in myeloma outcomes but had not honed in on the experience of young adult patients, who make up a growing proportion of diagnosed patients, said Dr. Azzouqa.
He and his associates analyzed Surveillance Epidemiology and End Results (SEER) data on patients diagnosed between ages 18 and 40 years with histologically confirmed multiple myeloma. The dataset spanned 1973-2014 and included 1,460 patients, of whom about 60% were male. Median age at diagnosis was 37 years; 47% of patients were non-Hispanic white, 28% were non-Hispanic black, 18% were Hispanic, 5.5% were Asian, and about 1% were of other ethnicities.
For young Hispanic patients with myeloma, 5-year survival improved from 39% before 1996, when stem cell transplants and novel therapies became available, to 56% from 2002 onward. This change was not statistically significant (P = .08), and 10-year survival rates also did not change significantly (from 21% to 33%; P = .13).
Five-year and 10-year survival did improve significantly for both genders (P = .0001) and among non-Hispanic blacks (P = .0001) and non-Hispanic whites (P = .0001).
Racial/ethnic subgroups did not differ significantly by median age at diagnosis, gender distribution, or listed cause of death, Dr. Azzouqa noted. Thus, reasons for the difference in survival for Hispanic patients remain unclear. Perhaps they reflect differences in disease biology, treatment response, or access or use of effective novel therapies, he said.
The researchers had no external funding sources. Dr. Azzouqa had no conflicts of interest. Lead author Dr. Sikander Ailawadhi disclosed ties to funding Pharmacyclics, Amgen, Novartis, and Takeda.
SOURCE: Ailawadhi S et al.