At the 2025 San Antonio Breast Cancer Symposium (SABCS), new data presented by Sarah Poland, University of Chicago, Illinois, USA, highlighted ongoing racial and socioeconomic disparities in both disease presentation and treatment initiation among patients with de novo metastatic HR+/HER2 negative breast cancer. The retrospective analysis used National Cancer Database data from 2010 to 2022 and included 72,874 patients, with a mean age of 63.4 years.
Hormone receptor positive disease represents the largest subgroup of metastatic breast cancer in the United States. Although advances such as CDK4/6 inhibitors have improved survival, outcomes remain uneven across racial and ethnic groups. This study sought to better define how those inequities emerge at diagnosis and during early treatment.
Unequal patterns of metastatic presentation
The study population was predominantly White at 75%, followed by Black patients at 15%, Hispanic patients at 6%, and Asian or Pacific Islander patients at 4%. Across the full cohort, bone-only metastases were most common at diagnosis, occurring in 64.4% of patients, while visceral disease occurred in 38.1% and brain metastases in 5.9%.
When stratified by race and ethnicity, important differences emerged. White patients were more likely to present with bone-only disease, with rates exceeding 66%. In contrast, Black and Hispanic patients more frequently presented with visceral metastases involving the liver or lung and had higher proportions of brain metastases at diagnosis. These differences were statistically significant and consistent across the large national dataset.
Delays in starting treatment
Disparities were also evident in the timing of treatment initiation. Median time from diagnosis to endocrine therapy was 34 days for White patients, compared with 39 days for Black patients and 42 days for Hispanic patients. Similar gaps were seen for chemotherapy and radiation therapy, with White patients consistently starting treatment sooner. Radiation therapy delays were particularly pronounced, with median initiation times of 46 days for White patients versus 66 days for Hispanic and Asian or Pacific Islander patients.
Together, the findings underscore persistent inequities in access to timely cancer care and highlight the need for system-level interventions to reduce delays for historically underserved populations.
Reference
Poland S et al. Racial and socioeconomic disparities in patterns of metastatic disease presentation and treatment among patients with de novo metastatic HR+/HER2- breast cancer. Abstract PD1-02-03. SABCS 2025; 9-12 December.
