Racial Differences in Outcomes and Health Care Utilization Among Patients With HR-Positive, HER2-Negative Metastatic Breast Cancer Treated With CDK4/…

CDK4/6 inhibitors, when combined with endocrine therapy, have become the standard treatment for hormone receptor-positive, HER2-negative metastatic breast cancer (mBC). Despite their increasing use, there is a notable lack of real-world data that evaluates the impact of race on treatment outcomes and healthcare utilization. This study aims to fill that gap by examining the survival rates, progression-free survival (PFS), and healthcare utilization patterns among Black and White patients treated with these inhibitors. The research involved a retrospective cohort study utilizing the TriNetX Global Collaborative Network, focusing on adults aged 18 and older diagnosed with HR-positive/HER2-negative mBC. The study included patients who initiated treatment with palbociclib, ribociclib, or abemaciclib in conjunction with endocrine therapy. To ensure comparability, Black and White patients were matched based on several factors, including age, sex, and comorbidities such as hypertension and diabetes. The primary outcomes measured were all-cause mortality, PFS, and healthcare utilization, which was defined as emergency department visits or hospital admissions. Results from the study indicated that after matching, 2,093 Black patients were compared to 2,093 White patients. Interestingly, the all-cause mortality rates were similar across both groups at various time points, with a one-year hazard ratio of 1.05, indicating no significant difference in survival. Similarly, PFS was comparable, with a one-year hazard ratio of 0.97. However, the study revealed a stark contrast in healthcare utilization, where Black patients exhibited significantly higher rates of emergency department visits and hospital admissions compared to their White counterparts. At the one-year mark, 47.7% of Black patients had utilized emergency services or been admitted to the hospital, compared to 43.4% of White patients. This disparity persisted during long-term follow-up, suggesting that while treatment efficacy may be similar, the healthcare experiences of these two racial groups differ markedly. The findings underscore the need for targeted interventions to address these disparities, which may stem from differences in access to care, supportive services, or broader systemic issues within the healthcare system. Addressing these disparities is crucial for improving equity in cancer care delivery and ensuring that all patients receive the necessary support throughout their treatment journey.