Racial and Ethnic Disparities Along the Treatment Cascade Among Medicare Fee-for-Service Beneficiaries With Metastatic Breast, Colorectal, Lung, and Prostate Cancers.

purposeThis study evaluated racial and ethnic disparities along the treatment cascade for Medicare fee-for-service patients with metastatic breast, colorectal, lung, and prostate cancers and disparities in overall survival by treatment receipt and quantified factors contributing to these disparities.

methodsMedicare fee-for-service beneficiaries with newly diagnosed metastatic hormone receptor-positive/human epidermal growth factor receptor 2-negative breast, colorectal, non-small cell lung, and prostate cancers from the SEER-Medicare-linked database (2016-2020) were studied. We used multivariable logistic regression to evaluate disparities along the treatment cascade, multivariable Cox regressions to evaluate disparities in overall survival by treatment receipt, and Oaxaca-Blinder decomposition to quantify the contribution of factors related to disparities.

resultsOf 18,652 White, 1,898 Black, and 1,465 Hispanic beneficiaries, within 2 months of diagnosis, 78% of patients were alive and 87% saw a medical oncologist-without consistent disparities. There were disparities in receiving any systemic therapy: breast (59% of Black patients received systemic therapy, 60% Hispanic, 68% White,

conclusionCare delivery and policy interventions intended to narrow racial and ethnic overall survival disparities in Medicare patients with metastatic cancer should target disparities in not receiving first-line systemic therapy and address the unique needs of beneficiaries with low-income subsidy status or dual eligibility.