Autologous hematopoietic cell transplantation (AHCT) is a global standard of care for eligible patients with newly diagnosed multiple myeloma (MM), yet racial and ethnic disparities remain. According to findings published in Transplantation and Cellular Therapy, non-Hispanic Black patients had a longer time from diagnosis to AHCT and remained less likely to undergo AHCT compared with non-Hispanic white patients, though utilization rates have improved over the last 10 years. Investigators also found that younger age at consultation, shorter time from diagnosis to consultation, and lack of cardiac and renal comorbidities were associated with greater utilization of AHCT.
“Transplant utilization is catching up among Black patients, but more work is needed to overcome barriers to care, as it still remains lower,” said corresponding author Anita D’Souza, MD, MS, a professor of medicine at the Medical College of Wisconsin in Milwaukee.
The retrospective cohort study included all new patients recorded in an institutional tumor registry who underwent consultations for MM between January 1, 2012, and December 31, 2022. The investigators calculated AHCT use and analyzed the associated factors. Excluded patients had prior stem cell transplant, non-MM plasma cell disorders, or concurrent amyloidosis, plasma cell leukemia, hematologic malignancy, or solid tumor.
Race and ethnicity were self-reported. Of the 1,266 patients, 82.1% were non-Hispanic white (42.5% female), 13.4% were non-Hispanic Black (55.3% female), and 4.4% were others (Hispanic, Asian, American Indian, or Alaska Native; 41.1% female). The median age at consultation was 66 years (range = 23-97) overall, 66 for non-Hispanic white, 63 for non-Hispanic Black, and 59.5 years for others. AHCT use stood at 76%, 77.8%, 64.7%, and 76.8%, respectively. Factors associated with AHCT receipt included younger age, high-risk cytogenetics, International Staging System stage I, lack of comorbidity, and shorter time from diagnosis to consultation.
“After the initial consultation, 76% of the overall cohort received a stem cell transplant — 78% among non-Hispanic white patients versus 65% for non-Hispanic Black patients (p<0.01),” Dr. D’Souza said.
From 2012-2017 to 2018-2022, AHCT use in non-Hispanic Black patients increased from 57.5% to 69.8%. For the non-Hispanic white patients, AHCT use stood at 79.1% and 76.7%, respectively. The most frequently reported reasons for not receiving AHCT included patient preference (31%), older age (28%), comorbidity (22%), early mortality (9%), and lack of caregiver support (8%). The non-Hispanic white group had greater AHCT use than the non-Hispanic Black group (odds ratio [OR] = 3.32; 95% CI 2.17-5.08; p<0.0001). Absent cardiac (OR=1.88; 95% CI 1.35-2.62; p=0.0002) or renal comorbidity (OR=3.23; 95% CI 2.03-5.15; p<0.0001) were linked to receiving AHCT. Older age at consultation (OR=0.89; 95% CI 0.87-0.90; p<0.0001) and a longer time from diagnosis to consultation (OR=0.97; 95% CI 0.95-0.98; p<0.0001) were linked to lower AHCT use.
Over time, AHCT use remained stable among non-Hispanic white patients and increased among non-Hispanic Black patients, but “race remained significantly associated with lower transplant utilization after adjusting for various factors, even in recent years,” Dr. D’Souza said. AHCT use is catching up among non-Hispanic Black patients, but barriers to care still exist.
“Other studies have documented that patients with MM who are treated at high-volume centers have better survival. Our study shows that those referred to a high-volume center early after diagnosis had more transplant utilization. Second, comorbidities, e.g., renal disease, previously associated with lower transplant utilization are no longer significantly associated with not doing a transplant,” Dr. D’Souza said. “My main takeaway for clinicians is to refer patients with myeloma to high-volume or academic centers for at least one evaluation for transplant or clinical trials early after diagnosis. Every patient, regardless of age and comorbidities, may be able to benefit.”
Limitations to the study included that the results were from a single transplant center, so they may not apply to other health care centers. Most patients were required to have insurance, representing an access issue for most cancer centers in the U.S. Because the non-Hispanic Black patients were younger at diagnosis, they were more likely to be uninsured or underinsured without access to Medicare. Another limitation was the small number of Hispanic, Asian, and American Indian or Alaska Native patients, grouped as others, which did not allow for subgroup analyses.
Future studies are needed that focus on “statewide geospatial analyses and qualitative research in patients with MM and physicians treating MM … to better understand barriers to AHCT with a goal of continuing to improve health equity in MM,” the authors concluded.
Any conflicts of interest declared by the authors can be found in the original article.
Reference
Wu JF, Estrada-Merly N, Dhakal B, et al. Racial and ethnic disparities in autologous hematopoietic cell transplantation utilization in multiple myeloma have persisted over time even after referral to a transplant center [published online ahead of print, 2024 Sept. 12]. Transplant Cell Ther. doi: 10.1016/j.jtct.2024.09.010.
