Reading time: 5 minutes
Aileen I Fernandez
Cancer is a complex disease associated with multiple factors. To fully understand the disease and find treatments, these multiple factors should be addressed. One of the intractable layers associated with this disease is the health disparity. The disparity here refers to a greater disease burden seen in one group in comparison to another. For example, there is a great amount of racial disparity found in breast cancer (BC), the second most commonly diagnosed cancer and the number one cause of cancer-related death in women in the United States. This disparity is especially prevalent in a subtype of breast cancer known as triple-negative breast cancer (TNBC). TNBC is the most aggressive type of breast cancer and has the worst prognosis. Currently, none of the available targeted therapies can be used to treat patients with TNBC. Therefore, there is a great need to find novel treatments. African- American (AA) women have higher breast cancer specific mortality, especially in TNBC, in comparison to Caucasian/White (CW) women. Some of the reasons for this disparity can be differences in income, screening and treatment barriers- all of which contribute to the diagnosis at later stages of the disease, which often makes it incurable. Data from a 2009 study showed that even after adjusting for factors such as age, stage, grade, and poverty index, AA women still have a much worse prognosis in comparison to CW women. This indicates that the disparity is observed due to both socio-economic as well as biological factors. For example, a study has shown that AA patients with breast cancer may have lower expression of FOXA1, a gene associated with breast cancer, in comparison to CW patients. Similarly, several other genes differentially expressed between AA and CW women were identified. This difference in the expression of these genes may attribute to more aggressive disease, poor clinical outcome, and metastatic potential of the disease in AA women . Because the health disparity in TNBC is multi-faceted and uncontrollable, it is important for scientists and oncologists to address the differences we can control, such as access to clinical trials, so that we can continue to look at cancer not as a single entity, but as the complex disease that it is.
There is a massive underrepresentation of AA patients in clinics and in clinical trials. AA patients have historically been less likely to participate in clinical studies due to (1) influence of mistreatment in past studies, guinea pig fear factor, barriers to trust and (2) researchers/medical professionals not asking AA patients to participate in trials. The first part begins with past studies such as the infamous Tuskegee syphilis study in which African- American men were enrolled in a study looking at the effects of syphilis, promised medical care, but were never informed about their disease, nor treated for syphilis, even after the antibiotic penicillin was officially proven to successfully treat the disease. . This and several such instances have left an effect of systemic racism that is deep – rooted in our society, preventing patients from participating in clinical trials and studies. Additionally, due to lack of Information there is fear and hesitation in participating in studies and clinical trials. Due to these reasons, AAs have significantly higher Guinea Pig Fear Factor than CWs, as well as fear of negative outcomes (consuming toxic chemicals, mistreatment, lack of confidentiality). AA representation in research, experienced mistreatment, lack of clinician professionalism, and financial difficulties have all been identified as barriers to trust.
Second, recent studies have shown that when specifically asked, AAs are just as likely to be willing to participate as CW patients.This leaves other potential barriers to AA participation that need to be addressed including: study design, such as inclusion and exclusion criteria, i.e. co-morbidities; lack of cultural competency; and limited clinical trial availability in readily accessible institutions. The responsibility to clear this barrier now falls on the clinicians, researchers and others involved in developing clinical trials and studies. The inclusion of AAs in clinical trials will lead us to a better understanding of breast cancer and improve the study of cancer overall.
These are just a few of the implications of addressing disparity in cancer. By working to eliminate race disparities in cancer in manners that we can control, we can shift our focus onto the biology of cancer, keeping in mind the different roles of race and ethnicity in the biology of cancers such as TNBC.
Edited by Prathyusha Konda
Dietze EC, Sistrunk C, Miranda-Carboni G, O’regan R, Seewaldt VL: Triple-negative breast cancer in African-American women: disparities versus biology. Nature Reviews Cancer 2015, 15(4):248.
Grunda JM, Steg AD, He Q, Steciuk MR, Byan-Parker S, Johnson MR, Grizzle WE: Differential expression of breast cancer-associated genes between stage-and age matched tumor specimens from African-and Caucasian-American Women diagnosed with breast cancer. BMC research notes 2012, 5(1):248.
Lund MJ, Trivers KF, Porter PL, et al. Race and triple negative threats to breast cancer survival: a population-based study in Atlanta, GA. Breast Cancer Res Treat. 2009;113(2):357–370. doi:10.1007/s10549-008-9926-3
Scharff DP, Mathews KJ, Jackson P, Hoffsuemmer J, Martin E, Edwards D: More than Tuskegee: understanding mistrust about research participation. Journal of health care for the poor and underserved 2010, 21(3):879.
Wallington SF, Dash C, Sheppard VB, Goode TD, Oppong BA, Dodson EE, Hamilton RN, Adams-Campbell LL: Enrolling minority and underserved populations in cancer clinical research. American journal of preventive medicine 2016, 50(1):111-117.