Nov 15, 2024 Story by: Editor
Breast cancer remains the most common cancer and a leading cause of cancer-related deaths among women in the United States. The American Cancer Society (ACS) estimates that in 2024, over 310,720 invasive breast cancer cases and 56,500 cases of ductal carcinoma in situ (stage 0) will be diagnosed nationwide. While a 42% reduction in breast cancer mortality over the past three decades reflects improved awareness, early detection, and advanced treatments, significant disparities persist between Black and white women in the U.S.
A Persistent Mortality Gap
ACS data reveal a glaring disparity in breast cancer outcomes. While incidence rates are comparable between Black and white women, the mortality rate among Black women is 38% higher. Among women under 50, the disparity is even starker: Black women in this age group face double the mortality rate of their white counterparts. Although advancements in detection and treatment have reduced overall mortality, these breakthroughs have not equally benefited all demographics, with these gaps remaining for over a decade.
Understanding the Disparities
The factors contributing to this disparity are multifaceted. Social determinants, such as socioeconomic status, geographic location, and lifestyle, play a role. Black women are statistically more likely to experience obesity, diabetes, heart disease, and lower breastfeeding rates—all recognized risk factors for breast cancer. Limited access to health insurance and healthcare facilities further exacerbates disparities, affecting timely screenings and treatment completion.
Biological factors also contribute significantly. Aggressive subtypes, such as triple-negative breast cancer (TNBC) and inflammatory breast cancer, are more prevalent among Black women, who are often diagnosed at younger ages and in more advanced stages.
Two major clinical trials, TAILORx and RxPONDER, revealed racial disparities in breast cancer outcomes. Dr. Joseph Sparano, a lead investigator, reported on TAILORx findings, which showed higher early recurrence rates in Black women compared to white women. Meanwhile, RxPONDER results indicated that Black women with HR-positive/HER2-negative breast cancer experienced worse outcomes despite similar recurrence scores. Studies suggest that breast tumors in Black women may respond differently or become resistant to endocrine therapies.
A 2017 study identified four factors accounting for 76.3% of excess breast cancer mortality risk among Black women: lack of private health insurance (37%), tumor characteristics (23.2%), comorbidities (11.3%), and treatment differences (4.8%).
Dr. Marianna Chavez MacGregor’s recent research highlighted how expanding Medicaid under the Affordable Care Act reduced survival disparities in stage 4 breast cancer, emphasizing the importance of healthcare access.
Moving Toward Solutions
The National Cancer Institute suggests solutions, including statewide cancer screening programs targeting underserved populations and addressing biological differences across racial groups. A 2019 city-level study demonstrated that increased access to advanced mammography facilities narrowed the mortality gap.
Despite significant progress in understanding breast cancer biology, most clinical trials focus on white women, underscoring the need for greater Black participation in research. Identifying unique biomarkers in aggressive tumors could lead to more personalized and effective treatments.
Research Efforts to Bridge the Gap
The Breast Cancer Research Foundation (BCRF) supports numerous projects aimed at addressing disparities:
- Dr. Christine Ambrosone and Dr. Chi-Chen Hong: Studying immune cells in breast tumors to understand tumor aggressiveness.
- Dr. Fergus Couch: Investigating gene mutations like BARD1 and RAD51D, which are more common in Black women with TNBC.
- Dr. Melissa Davis: Exploring relationships between social determinants, ancestry, and tumor biology.
- Dr. Laura Esserman: Examining immunological features to inform better interventions.
- Dr. Carmen Guerra: Mitigating unconscious bias in clinical trial enrollment for Black women.
BCRF also invests in career development for early-career researchers addressing disparities.
A Global Perspective
Breast cancer is the most diagnosed cancer worldwide. Studies in underserved regions, like those by Drs. Lawrence Shulman and Cyprien Shyirambere in Rwanda, aim to improve early detection and reduce mortality. Dr. Olufunmilayo Olopade’s work in Nigeria focuses on tumor biology and clinical trial infrastructure to enhance care in low-resource settings.
Corporate Support
Marking 30 years of advocacy, The Estée Lauder Companies Charitable Foundation donated $15 million to the BCRF to address health equity in breast cancer research.
Efforts to address disparities continue, to ensure that advancements in breast cancer treatment benefit all women, regardless of race or socioeconomic background. Source: BCRF
