Study Identified Factors Related to Multiple Myeloma Disease Outcomes

In patients with multiple myeloma (MM), age at diagnosis, tumor mutations, and clonal hematopoiesis may explain racial and ethnic differences in outcomes, according to new data presented at the American Society of Hematology’s 2021 Annual Meeting.

To clarify the mechanisms behind racial and ethnic disparities in MM outcomes, researchers at the Moffitt Cancer Center in Tampa, Florida, investigated the demographic, clinical, and molecular features of the disease in a diverse population of nearly 500 patients by extracting data from a cancer registry and electronic medical records.

They also purified MM tumor cells from bone marrow aspirates by using CD138 affinity chromatography, isolated DNA from tumor cells and whole blood for each participant, and generated whole exome sequencing (WES) data.

In addition, they characterized tumor somatic mutations by using paired tumor‑normal WES and classified clonal hematopoiesis based on blood-derived somatic mutations by using paired tumors and reference populations as germline comparators. The outcomes they evaluated included overall survival and progression-free survival.

A younger median age at diagnosis was found for participants who were non-Hispanic Black and Hispanic than for participants who were non-Hispanic White (p = 0.0000), and overall survival was found to be associated with age at diagnosis. Overall survival was also associated with International Staging System category, treatment with hematopoietic stem cell transplantation, and treatment regimen category. After adjusting for these 4 variables, no statistically significant association was found between overall survival and race or ethnicity.

Moreover, after adjusting for age, no statistically significant association was found between overall survival by race or ethnicity and clonal hematopoiesis status or between progression-free survival and race or ethnicity.

Higher rates of genetic mutations in tumor cells were found in SP140, AUTS2, and SETD2 in participants who were Black than in participants who were non-Hispanic White, and IRF4 was most often mutated in Hispanics.

“Our data suggest that age at diagnosis, tumor mutations, and [clonal hematopoiesis] may all contribute to clinical disparities observed in patients with MM,” the researchers concluded.

—Ellen Kurek

Reference:

Gillis N, Peres LC, Colin-Leitzinger CM, et al. Racial and ethnic differences in clonal hematopoiesis, tumor markers, and clinical outcomes of patients with multiple myeloma. Paper presented at: American Society of Hematology 2021 Annual Meeting; December 8-14, 2021; Atlanta, Georgia, and Virtual. https://ash.confex.com/ash/2021/webprogram/Paper147340.htm