Coalition Voice

While the term “breast cancer” sounds like a single disease, there are in fact several different types of breast cancer. The four main subtypes of breast cancer are luminal A, luminal B, HER2-positive, and triple negative (1). Luminal A and Luminal B breast cancers are often hormone receptor-positive, expressing estrogen receptors (ER), progesterone receptors (PR), or both (2). HER2-positive breast cancers overexpress a protein known as human epidermal growth factor receptor 2 (HER2) (3). Triple negative breast cancer refers to the absence of estrogen, progesterone, and HER2 receptors (4).

In such instances, without these receptors present on the cancer cells, triple negative breast cancer (TNBC) responds to fewer drug treatments that work on the hormone receptors, making it a more difficult subtype to treat (5). TNBC makes up around 10-15% of breast cancer diagnoses and is also a particularly aggressive subtype, with high rates of recurrence (4,5). Triple negative breast cancer is more commonly diagnosed in Black women compared to their White counterparts, highlighting the prevalence of racial disparities in cancer incidence and rates of mortality (6).

The increased prevalence of triple negative breast cancer in Black women is compounded by the persistent, racist institutional oppressions that women of color too often face. Social determinants of health – i.e., access to healthcare, socioeconomic status and stability, employment and housing – play a key role in all health outcomes for individuals, and cancer is no exception. Black women have a 40% higher rate of mortality from breast cancer compared to White women, even though White women are diagnosed with breast cancer more often (7).

While scientists aim to discover why Black women are diagnosed with TNBC at greater than twice the rate of White women (8), it is crucial to provide education and support to women before ever receiving a diagnosis. One such educator is Dr. Diva Melvin.

A biomedical scientist from Tougaloo, Mississippi, Dr. Melvin focuses on research and education surrounding triple negative breast cancer in African American women living in the Mississippi Delta. Originally from Mississippi, Dr. Melvin received her Bachelor of Science in Biology from Tougaloo College and her PhD in Biochemistry and Cancer Biology from Meharry Medical College.

Currently, she is prioritizing outreach to her community to inform on the different breast cancer subtypes. As an African American woman, Dr. Melvin is passionate about researching a disease that disproportionately impacts her community. Through providing education on triple negative breast cancer, she promotes self-awareness and the importance of women being their own advocates. Additionally, Dr. Melvin discusses lifestyle choices, such as healthy eating habits and the health benefits of breastfeeding.

She advocates for the importance of having Black scientists in research, as their lived experiences add a level of compassion and cultural competency to their work. As Dr. Melvin puts it, “Diversity is key.” When it comes to her research and advocacy surrounding triple negative breast cancer, she comes to the work with the perspective of an African American woman researching members of her community who often face significant challenges in accessing the healthcare they need.

In parts of Mississippi – not unlike many other states in the country – there are healthcare “deserts” where the closest medical facilities could be several hours away by car or bus. In such instances, those in need of medical care or cancer treatment are faced with the difficult task of taking time off work, finding reliable transportation, and possibly finding childcare. Such burdens are made even more arduous in states like Mississippi that did not expand Medicaid following the passage of the Affordable Care Act. This has resulted in a significant percentage of Americans who make too much money to qualify for Medicaid, yet they cannot afford the costs of their own health insurance plans (9).

It is evident that both research and advocacy are needed to support those living with triple negative breast cancer. A subtype that is most commonly diagnosed in Black women, the racial disparities in triple negative breast cancer combined with the psychosocial challenges and systems of oppression that Black women are consistently faced with result in poorer health outcomes for this demographic. This is both a medical concern and a matter of social and racial justice.

Thank you to Dr. Melvin for her continued work in research and advocacy surrounding triple negative breast cancer in African American women. Her efforts are deeply appreciated by the Breast Cancer Coalition.

1. https://www.ncbi.nlm.nih.gov/books/NBK583808/
2. https://pmc.ncbi.nlm.nih.gov/articles/PMC4127612/#:~:text=Luminal%2DA%20subtype%20is%20defined,lower%20than%20the%20other%20subtypes.
3. https://www.pennmedicine.org/cancer/types-of-cancer/breast-cancer/types-of-breast-cancer/her2-positive-breast-cancer
4. https://www.cancer.org/cancer/types/breast-cancer/about/types-of-breast-cancer/triple-negative.html
5. https://www.mdanderson.org/cancerwise/triple-negative-breast-cancer-5-things-you-should-know.h00-158986656.html
6. https://pmc.ncbi.nlm.nih.gov/articles/PMC5470637/#:~:text=Triple%2Dnegative%20breast%20cancer%20(TNBC,than%20women%20of%20European%20descent.
7. https://www.cancer.org/research/acs-research-news/breast-cancer-death-rates-are-highest-for-black-women-again.html
8. https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2810196
9. https://stateline.org/2024/07/19/in-the-10-states-that-didnt-expand-medicaid-1-6m-cant-afford-health-insurance/