Black Women and Breast Cancer: Why Disparities Persist and How to End Them
By BCRF | January 14, 2021
By BCRF | January 14, 2021
In the United States, breast cancer continues to be the most common cancer diagnosed among women after non-melanoma skin cancer, and it is the second leading cause of cancer death. This year, the American Cancer Society estimates that more than 281,550 new cases of invasive breast cancer and 49,290 new cases of non-invasive breast cancer will be diagnosed in women in the United States. While there has been an overall 40 percent decline in breast cancer deaths over the last 30 years—thanks to gains in awareness, early diagnosis, and treatment—there is a persistent mortality gap between Black women and white women.
Data compiled by the American Cancer Society highlight the need to continue working toward closing this devastating gap. Previously, Black women were found to have a slightly lower incidence rate of breast cancer. This is no longer the case: The incidence rate for Black women is close to that of white women. However, the mortality rates are markedly different, with Black women having a 40 percent higher death rate from breast cancer. Among women under 50, the disparity is even greater: The mortality rate among young Black women is double that of young white women. It is clear that the advances in treatment that have dramatically reduced breast cancer mortality overall have not equally benefitted all groups.
What accounts for Black women's breast cancer disparities?
The gap in breast cancer incidence and outcome among Black women is complex and multifactorial. Social, economic, and behavioral factors may partially account for disparities. Black women are more likely to have diabetes, heart disease, and obesity, and are less likely to breastfeed after childbirth—all of which are risk factors for breast cancer. They are also more likely than white women to have inadequate health insurance or access to health care facilities, which may affect screening, follow-up care, and completion of therapy.
Through continued research, it is becoming increasingly clear that biology also plays a role. Black women are disproportionately affected by more aggressive subtypes, such as triple-negative breast cancer (TNBC) and inflammatory breast cancer, and they are more likely to be diagnosed at younger ages and at more advanced stages of the disease.
Working toward a solution
According to the National Cancer Institute, disparities in cancer care can be improved several ways, including by creating statewide cancer screening programs that are accessible to underserved populations and by addressing the biological differences in breast cancer across racial and ethnic groups. A 2019 study that analyzed characteristics of breast cancer patients on a city level showed that women with more resources (such as education and income) may be better equipped to take advantage of healthcare advances. Indeed, cities that have confronted this problem by increasing access to state-of-the art mammography facilities made significant progress in narrowing the breast cancer mortality gap between Black and white women.
The biology of breast cancer is inherently complex, which is why we often hear the phrase, “Every woman’s breast cancer is unique.” While we have made significant progress in understanding the molecular drivers of breast cancer, most studies and clinical trials are conducted in white women. Expanding Black women’s participation in research is critical. We have only recently been able to decipher some of the underlying biology to explain the higher incidence of aggressive tumors in Black women and to identify biomarkers that could ultimately inform personalized therapies and improve outcomes for Black women diagnosed with breast cancer.
How BCRF is committed improving outcomes for Black women with breast cancer
BCRF recognizes the continued need for more research on disparities faced by Black women. Our researchers specifically working in this area include:
Dr. Nikhil Wagle is leveraging social media to improve our understanding of metastatic breast cancer. His Metastatic Breast Cancer Project is empowering patients to share their tumor and medical history data in an online registry to accelerate research on metastatic disease. His research aims to increase participation of Black patients with metastatic breast cancer in this project, as this community is typically underrepresented in clinical trials.
Drs. Funmi Olopade and Dezheng Huo are identifying genetic factors responsible for TNBC and those that specifically predispose Black women to this aggressive breast cancer. Dr. Olopade and colleagues were the first to discover that Black women have a higher than expected incidence of mutations in the BRCA1 and BRCA2 genes, as well as other inherited susceptibility genes, compared to their white counterparts.
Work led by Dr. Charles Perou and BCRF collaborators has uncovered differences in biology in breast tumors of Black women compared to those in white women that may be targetable to decrease the disparities in breast cancer outcomes.
Dr. Fergus Couch has identified inherited mutations in breast cancer susceptibility genes that confer an increased risk of TNBC and may be important for screening in high-risk Black women. Recently, Couch and his collaborators examined gene mutations in a large, racially diverse population of American women. This study showed that mutations in the BARD1, RAD51C, and RAD51D genes, while very uncommon, appear more frequently in Black women with breast cancer and are associated with an increased risk of both TNBC and ER-negative breast cancer. Read more here.
Dr. Annette Stanton is conducting research on the unique psychological experiences of Black women diagnosed with breast cancer to help them better cope and decrease depressive symptoms.
Dr. Mariana Chavez MacGregor is working on ways to prevent treatment delays among underserved populations.
Dr. Laura Esserman is examining the immunological features of breast cancers in Black women to gain a better understanding of the spectrum of disease and the types of interventions that might improve outcomes.
Dr. Sandra Swain is analyzing the genetics and blood of Black and white women who are taking the CDK 4/6 inhibitor ribociclib (Kisqali®) to treat their breast cancer. This will help to uncover mechanisms behind differences in the variable responses to ribociclib, thus providing a foundation for future clinical treatment strategies.
A deeper understanding of tumor biology, its variations among people of different races, and the intersection of biology and social determinants of health holds the promise to improve prevention strategies, early detection, and treatment of breast cancer. BCRF continues to work toward this goal.
This article was updated to reflect 2021 data and research projects.
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