Black Women With Breast Cancer Have Higher Risk of Death Compared With White Women

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Black women who develop breast cancer are approximately 40% more likely to die of the disease compared with White women. Previously, it was unclear whether this disparity was present across all breast cancer subtypes, and a new study published in the Journal of Clinical Oncology confirms this. The disparity ranges from about 17% to 50% depending on the type of breast cancer.¹

Breast cancer is the most diagnosed cancer among women in the US, and it is the second leading cause of cancer-related death.¹ Although breast cancer is often discussed as a single disease, breast cancer has multiple subtypes that can differ in treatment, prognosis, and risk factors.¹

For this meta-analysis, the investigators evaluated studies published from January 1, 2000, to December 31, 2022. The included studies compared the survival between Black and White female patients with breast cancer within subtypes defined by hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2)/neu (also known as ERBB2) status. Random-effects models were used to combine study-specific results as well as generate pooled relative risks (RRs) and confidence intervals (CIs) for breast cancer-specific or overall survival (OS).²

A total of 228,885 patients with breast cancer (Black patients: n=34,262; White patients: n=182,466) across 18 studies were identified and assessed. Overall, Black women had a higher risk of breast cancer–related death across all tumor subtypes compared with their White counterparts.^1,2 The risk of breast cancer death was approximately 50% higher among HR+/HER2- tumors (RR, 1.50 [95% CI, 1.30 to 1.72]), 34% higher for HR+/HER2+ tumors (RR, 1.34 [95% CI, 1.10 to 1.64]), 20% higher for HR-/HER2+ tumors (RR, 1.29 [95% CI, 1.00 to 1.43]), and 17% for HR-/HER2- tumors (hazard ratio, 1.17; 95% CI, 1.10 to 1.25). Additionally, Black women had poorer OS for all subtypes.²

“There had been an anecdotal sense in the research community that differences in survival between Black and White women were greater for the most treatable forms of the disease—tumors that carry HRs—and smaller for the historically less-treatable, hormone-negative tumors,” said study senior author Erica Warner, ScD, MPH, cancer epidemiologist at Massachusetts General Hospital, and founding member of the Mass General Brigham health care system, in a news release.¹

Further, the investigators noted that because hormone-negative tumors are less common than those that are hormone-positive, the racial disparities in breast cancer survival for hormone-negative subtypes were likely not observed previously because individual studies lacked statistical power. The authors also acknowledged that underrepresentation may also contribute to this.¹

“There may also be differences in the biological characteristics of some tumor subtypes between racial groups that our therapies are not attuned to, potentially because of underrepresentation of Black women in clinical trials,” Warner said in the news release.¹

These disparities are not just present in breast cancer, but a plethora of cancer types. Authors of a study published in Cancer Medicine evaluated the treatment patterns and survival in multiple myeloma.³ They assessed racial differences in the receipt of treatment, timing of treatment initiation, and survival between non-Hispanic Black patients and non-Hispanic White patients, and found that during the first year following diagnosis, approximately 59.5% of Black patients and 64.8% of White patients received treatment. Additionally, Black patients who received treatment within 1 year of diagnosis increased from 51.5% in 2007 through 2009 to 64.5% in 2014 through 2017. For White patients, the growth was about 54.3% to 71.4% during this same period.³

Further, treatment initiation for Black patients remained noticeably late even after adjustments for baseline characteristics were made (HR = 0.91, 95% CI: 0.85–0.97, p < .01). Treatment initiation was also earlier for patients who were diagnosed in more recent time periods (2014–2017: HR = 1.54, 95% CI: 1.46–1.63; 2010–2013: HR = 1.37, 95% CI: 1.30–1.44) than for those who were diagnosed in 2007 through 2010.³

Another study found similar trends in adolescent and young adult (AYA) patients who have cancer. In the JAMA Network Open study, the risk of late-stage diagnosis and OS for the 10 deadliest cancers were evaluated.⁴ Although most patients in the study were White (n=240,192; 82%), Black patients (n=40,851; 14%) were among the groups who were more likely to have late-stage diagnoses (AOR, 1.40; 95% CI, 1.36-1.43) for nearly all cancer types. These cancers included breast (AOR, 1.28; 95% CI, 1.22-1.34), cervix (AOR, 1.22; 95% CI, 1.11-1.34), colon or rectum (AOR, 1.19; 95% CI, 1.10-1.29), lung (AOR, 1.40; 95% CI, 1.18-1.67), lymphoma (AOR, 1.37; 95% CI, 1.29-1.45), melanoma (AOR, 2.49; 95% CI, 1.81-3.39), and testis (AOR, 1.37; 95% CI, 1.16-1.60).⁴

At the median follow-up of 62 months (IQR, 34-102 months), OS varied significantly by race across nearly all cancers except for ovarian and central nervous system cancers. The mortality rate was approximately 24% for Black patients, compared with White patients who had a mortality rate of 15%.⁴

The investigators of the original study emphasized that these racial disparities are not inevitable, and that multiple interacting factors contribute to these outcomes.^1,2 Improvements of these racial disparities would require multilevel interventions to both address and achieve health equity, with methods available including helping patients navigate the health care system, proactively identifying and addressing social needs and connecting patients with proper resources, and implementing systems that can alert health care professionals of missed appointments or any unmet care milestones.^1,2 Both the Cancer Medicine and JAMA Network Open studies are additional indicators that such interventions are necessary and can improve the outcomes of Black patients with cancer.^3,4

The investigators propose interventions at the national level, such as Accountability for Cancer Care through Undoing Racism and Equity (ACCURE), which can help close gaps in survival and mortality between Black and White female patients.¹

“[Our study] findings underscore a stark reality in our health care system: Black women are facing higher risks of death from breast cancer compared to their White counterparts, across all types of the disease. This disparity isn't just about biology,” emphasized co-author Paulette Chandler, MD, MPH, associate epidemiologist in the Division of Preventive Medicine at Brigham and Women’s Hospital, and founding member of the Mass General Brigham health care system, in the news release. “It's a call to action for health care providers, policymakers, and communities alike to confront these inequities head-on and strive for meaningful change in breast cancer outcomes.”¹

REFERENCES

1. Mass General Brigham. Black Women Have a Higher Risk of Dying from All Types of Breast Cancer, Meta-Analysis Reveals. News release. September 17, 2024. Accessed September 18, 2024. https://www.massgeneralbrigham.org/en/about/newsroom/press-releases/black-women-have-higher-risk-of-dying-from-all-types-of-breast-cancer

2. Torres JM, Sodipo MO, Hopkins MF, Chandler PD, Warner ET. Racial Differences in Breast Cancer Survival Between Black and White Women According to Tumor Subtype: A Systematic Review and Meta-Analysis. JCO 0, JCO.23.02311 doi:10.1200/JCO.23.02311

3. McGovern, G. Black Patients More Likely to Experience Delays in Multiple Myeloma Treatment Initiation. Pharmacy Times. February 2, 2024. Accessed September 18, 2024. https://www.pharmacytimes.com/view/black-patients-more-likely-to-experience-delays-in-multiple-myeloma-treatment-initiation

4. McGovern, G. Study Finds Race Impacts Cancer Stage at Diagnosis and Patient’s Overall Survival. Pharmacy Times. September 3, 2024. Accessed September 18, 2024. https://www.pharmacytimes.com/view/study-finds-race-impacts-cancer-stage-at-diagnosis-and-patient-s-overall-survival