Racial Disparities in Breast Cancer Outcomes

With the utilization of screening mammography and adjuvant endocrine therapy, breast cancer mortality has decreased by an impressive 40% from 1989 to 2017.¹ However, this reduction in mortality has not impacted racial groups equally. While the lower incidence of breast cancer in Black women than in non-Hispanic white women should theoretically correlate to a lower breast cancer mortality, breast cancer mortality is approximately 40% higher in Black female patients than in non-Hispanic white women.² Some of the main contributing factors to this stark disparity include the difference in the efficacy of screening methods and the difference in access to healthcare services.

Breast cancer can be characterized by whether cancer cells have the presence of hormone receptors (HR-positive tumors) or the absence of hormone receptors (HR-negative tumors). HR-negative tumors include triple-negative tumors which are considered to be one of the more aggressive tumors. Mammography has been suggested to not be very sensitive for detection of triple-negative tumors since these tumors typically lack the characteristic irregular shape and calcifications of other breast tumors.³ As compared with non-Hispanic white women, Black women have an 81% higher rate of triple-negative cancer, making it difficult to detect breast cancer in this population through a screening mammogram.² 

In terms of access to breast cancer screening, a study found that non-Hispanic Black women are less likely to utilize mammogram screening as opposed to non-Hispanic white women.⁴ It was also found that after having an abnormal screening mammogram, Black and Hispanic women were more likely to experience a delay in having follow-up diagnostic imaging than non-Hispanic white women, putting these patients at greater risk for poor outcomes.⁵ A recent program was implemented to address this issue and ensure that abnormal screening mammograms were followed up with a same-day diagnostic mammogram, preventing the potential for delays in further management for all patients.⁶

Several factors may be contributing to the racial disparities we see in breast cancer outcomes. Being aware of these disparities can help us focus on closing this gap through developing screening methods that would more effectively screen for triple-negative tumors, increasing awareness of breast cancer, and improving access to screening and diagnostic services.

ACR^® Resources

• To learn more on the topic of health equity, view the on-demand webinar series Breaking Barriers: A Collaborative Approach to Advancing Health Equity in Medical Imaging. Commit to positively impact healthcare equity in radiology and sign the pledge.
  
  
• The ACR is currently conducting the Tomosynthesis Mammographic Imaging Screening Trial (TMIST), the first randomized controlled trial that seeks to identify women in which digital breast tomosynthesis (DBT) may outperform (2D) digital mammography in reducing advanced breast cancer development. The study will create the world’s largest curated dataset of breast cancer screening clinical data, images and bio-specimens to help researchers tailor future screening to a woman’s individual risk. In early 2022, the trial was more than halfway to its recruiting goal, with more than 20% of participants in the United States being Black.

References

1. 1. DeSantis, C.E., Ma, J., Gaudet, M.M., Newman, L.A., Miller, K.D., Goding Sauer, A., Jemal, A. and Siegel, R.L. “Breast Cancer Statistics,” CA: A Cancer Journal for Clinicians, 2019:69(6), 438–451. Available at: https://doi.org/10.3322/caac.21583
   
   
2. Jatoi, I., Sung, H. and Jemal, A. “The Emergence of the Racial Disparity in U.S. Breast-Cancer Mortality,” New England Journal of Medicine, 2022:386(25), 2349–2352. Available at: https://doi.org/10.1056/nejmp2200244
   
   
3. William M., M.G. and Sonya, B. “Triple-Negative Breast Cancer: What Crucial Information Can Imaging Add to the Diagnosis, Treatment and Prognosis?,” International Journal of Women's Health and Wellness, 2019:5(1). Available at: https://doi.org/10.23937/2474-1353/1510087
   
   
4. Ahmed, A.T., Welch, B.T., Brinjikji, W., Farah, W.H., Henrichsen, T.L., Murad, M.H. and Knudsen, J.M. “Racial Disparities in Screening Mammography in the United States: A Systematic Review and Meta-Analysis,” Journal of the American College of Radiology, 2017:14(2). Available at: https://doi.org/10.1016/j.jacr.2016.07.034
   
   
5. Press, R., Carrasquillo, O., Sciacca, R.R. and Giardina, E.-G.V. “Racial/Ethnic Disparities in Time to Follow-Up After an Abnormal Mammogram,” Journal of Women's Health, 2008:17(6), 923–930. Available at: https://doi.org/10.1089/jwh.2007.0402
   
   
6. Achibiri, J., Dontchos, B.N., Mercaldo, S., Narayan, A., Miles, R.C., Lamb, L., Wang, G.X. and Lehman, C.D. “Reducing Racial Disparities in Time to Breast Cancer Diagnosis: Impact of Immediate Screening Mammogram Reads During the COVID Pandemic,” Journal of Clinical Oncology, 2021:39(15_suppl), 6508–6508. Available at: https://doi.org/10.1200/jco.2021.39.15_suppl.6508