Racial Disparities in the Use of Palliative Radiotherapy for Black Patients With Multiple Myeloma in the United States

Abstract

<h3>Purpose/Objective(s)</h3> Multiple myeloma (MM) is a hematologic malignancy that disproportionately affects African Americans (AA) and has a natural history that is often characterized by painful osseous lesions that are amenable to palliative radiotherapy (RT). There are known racial disparities in the definitive treatment of MM and pain management in general in the AA community compared to other racial groups. We sought to determine if racial disparities also exist in use of palliative RT for MM in the United States. <h3>Materials/Methods</h3> The National Cancer Database was queried for patients 18 years and older who were diagnosed with MM from 2004-2016 and received radiation. RT dose was limited to between (and including) 4Gy to 30Gy to exclude non-standard doses, incomplete courses, and patients treated for plasmacytoma. The main independent variable under investigation was race/ethnicity, defined as non-Hispanic white (NHW), non-Hispanic black (AA), Hispanic, and other race. Outcomes of interest included receipt of palliative RT within 12 months of MM diagnosis and death within 30 days of initiation of palliative RT. Additional covariates included socioeconomic factors, underlying health, and treatment factors. Multivariable logistic regression analyses were performed to measure the associations of patient race/ethnicity with the odds receiving radiation within 12 months of diagnosis and odds of death within 30 days of receiving the first course of RT. <h3>Results</h3> Of 23,728 NCDB multiple myeloma patients receiving palliative RT within 12 months of diagnosis, 15.5% of NHW patients, 14.3% of AA patients, 15.8% of Hispanic patients, and 14.4% of other racial/ethnic group patients received palliative RT. The odds of receiving RT were 13% less for AAs compared to NHWs (OR = 0.87, CI = 0.83-0.90, <i>P</i> < 0.0001). Of those receiving radiation, the odds of dying within 30 days of RT were 18% less for AAs compared to NHWs (OR = 0.82, 95% CI = 0.67-1.00, <i>P</i> = 0.046). <h3>Conclusion</h3> This study of the NCDB demonstrates that in addition to previously documented disparities in definitive management of MM, AA patients are also less likely to receive palliative RT within 12 months of diagnosis and at the end of life.