Racial Disparities in Clinical Outcomes of Hormone Receptor–Positive Breast Cancer

By: Julia Fiederlein Cipriano
Posted: Tuesday, January 10, 2023

According to Yara Abdou, MD, of the University of North Carolina, Chapel Hill, and colleagues, Black patients with hormone receptor–positive, HER2-negative, node-positive breast cancer experience worse invasive disease–free survival outcomes than their White counterparts—despite having similar 21-gene assay recurrence scores. An analysis of race and clinical outcomes in the RxPONDER trial was presented during the 2022 San Antonio Breast Cancer Symposium (SABCS; Abstract GS1-01).

The investigators focused on 2,833 non-Hispanic White, 248 non-Hispanic Black, 610 Hispanic, and 324 Asian patients with recurrence scores up to 25. The 5-year invasive disease–free survival rates among these racial subgroups were 91.5%, 87.0%, 91.4%, and 93.9%, respectively.

Based on a multivariable Cox model adjusting for the recurrence score and treatment arm, non-Hispanic White patients experienced better invasive disease–free survival outcomes than non-Hispanic Black patients (hazard ratio [HR] = 1.38; P = .048); however, they seemed to have worse outcomes compared with Asian patients (HR = 0.65; P = .034). Similar, yet nonsignificant, hazard ratios for invasive disease–free survival were observed between premenopausal (HR = 1.37) and postmenopausal (HR = 1.38) non-Hispanic Black patients.

There did not appear to be a significant interaction between the non-Hispanic Black versus non-Hispanic White cohorts and the treatment arm for either premenopausal or postmenopausal patients after adjusting for the recurrence score; however, according to the investigators, this analysis was limited by a small sample size. An analysis adjusting for treatment and the recurrence score found that, among postmenopausal patients, the non-Hispanic Black cohort had worse distant relapse–free survival outcomes compared with the non-Hispanic White cohort (HR = 1.69; P = .01); a similar, yet nonsignificant, trend was observed among premenopausal patients (HR = 1.74).

Data on treatment adherence over 5 years are not yet mature. However, non-Hispanic Black patients were more likely to accept their treatment assignment compared with non-Hispanic White patients (93.0% vs. 86.0%; P = .004).

Disclosure: For full disclosures of the study authors, visit sabcs.org.

2022 San Antonio Breast Cancer Symposium

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