SABCS 2020 Opens with Special Session on Disparities in Breast Cancer

Work from four BCRF investigators featured in wide-ranging discussion

Across the spectrum of breast cancer care, racial and ethnic disparities remain a persistent challenge. 2020 has brought increased awareness of and conversation about systemic racism in the United States, including its effects on healthcare, along with a continued call to action to ensure equitable care for all patients.

This year’s 43^rd annual San Antonio Breast Cancer Symposium opened with a session focused on racial disparities in breast cancer care and research. The session, “Setting the Stage for Health Equity, Collaboration and Partnership,” was sponsored by the American Association for Cancer Research and the Tigerlily Foundation, which provides education, awareness, advocacy, and support to young women throughout the course of their breast cancer journeys. Among Tigerlily’s signature initiatives is the Diversity and Inclusion Pledge for Black Women. BCRF signed the pledge earlier this year.

BCRF researcher Dr. Charles Perou and Maimah Karmo, founder and CEO of the Tigerlily Foundation, welcomed attendees and emphasized the urgency of implementing concrete solutions to healthcare inequity. 

“In breast cancer, it is well known that there exist racial disparities, where women of color have worse survival outcomes compared to white women with breast cancer, even when matched for age and stage,” Dr. Perou said in his opening remarks. 

RELATED: Where Racial Disparities Persist in Breast Cancer Care

Indeed, although white women are slightly more likely to be diagnosed with breast cancer, Black women are 40 percent more likely to die from their disease. Furthermore, Black, Hispanic, and Latina women are often diagnosed at a later disease stage than their white counterparts, resulting in worse prognoses and more limited treatment options.

Tigerlily advisory board member and medical student Shawn Johnson then set the stage to discuss the session’s 11 research projects addressing critical aspects of disparities in breast cancer. The session included four projects from BCRF-funded investigators.

“We still have a long way to go,” Johnson said. “If we’re really going to acknowledge the voices of patients of color [and improve] the role of racism in social determinants of health and health outcomes, then our research must be willing to name these risk factors—the same way that we do with pollution, access to deficient genetics, and other biologic factors.”

Socio-economic access matters

The session’s first topic, socio-economic factors, covered areas that are all affected by access to healthcare. 

BCRF researcher Dr. Kala Visvanathan’s lab concluded, for example, that racial disparities exist in the use of digital breast tomosynthesis (DBT), a 3D screening technique that detects breast cancer more effectively than traditional 2D mammography. Although there has been an uptake of DBT across all groups, Black and Asian women are significantly less likely than white women to be screened with DBT. Over time, this may significantly impact clinical outcomes.

Research studying populations in Miami, Fla. revealed that where one lives impacts cancer survival. Women with breast cancer living in extreme poverty and in racially segregated areas had a significantly greater chance of dying from the disease, according to the study results. The researchers created a valuable new index to capture these effects in a single metric and inform future research.

Finally, researchers from the National Surgical Quality Improvement Program examined a decade of data and highlighted that racial disparities in breast-conserving surgery (partial mastectomy and reconstructive surgery) have decreased, but more work needs to be done.

Commenting on these projects, Dr. Lisa Newman of Weill Cornell Medical College underscored the complex, socio-economic factors contributing to disparities in breast cancer care.

“Step one in correcting unequal [breast cancer] outcomes is absolutely dependent on our ability to overcome barriers in access to care,” she said.

Personalizing medicine for the underserved

The session then turned to discussion about underlying biological differences among populations. 

Research from the laboratories of BCRF investigators Drs. Dezheng Huo and Funmi Olopade determined that Black patients had a lower pathological complete response (pCR) rate (a strong surrogate for long-term survival) after neoadjuvant chemotherapy compared to white patients. The racial disparity in pCR rate was largest among hormone receptor (HR)-negative, HER2-positive patients, possibly due to biological differences beyond breast cancer subtype that could affect treatment response. 

Another project from Drs. Olopade and Huo stressed the need to understand genetic drivers of disparity and develop therapeutic strategies from these analyses. Genetic differences between Black and white TNBC and HR-positive, HER2-negative breast cancer patients’ tumors revealed unexplored molecular pathways that are altered in aggressive disease and that could inform new therapeutics.

RELATED: Racial Disparities in Breast Cancer: Why They Persist and How to Narrow the Gap

Other featured studies emphasized the gamut of biological factors underlying breast cancer disparities, including differences in immune microenvironments surrounding tumors that correlate with risk, subtype, age, and race, as well as differences in gene expression between TNBC patients of Ghanaian (West African) and Ethiopian (East African) ancestry that correlate with worse outcomes for West African women.

These projects all demonstrate the need for more extensive research into our fundamental biology so that patients can receive tailored treatment for their unique disease—the very definition of precision medicine for all.

“We’re only at the tip of the iceberg,” Dr. Olopade said. “When we begin to do real precision medicine, we’re not going to be stratifying based on new resources or new insurance or environment, age, and race—we’re going to be really looking at what that tumor looks like…and what we need to do to treat this patient, so that we have precision healthcare for all.”

Policy changes and disparities

The final topic of the session touched on the impact of policy changes on breast cancer outcomes. 

The expansion of Medicaid under the Affordable Care Act (ACA) made health insurance more accessible to many Americans. BCRF investigator Dr. Mariana Chavez Mac Gregor presented research demonstrating that Medicaid expansion reduced the proportion of patients experiencing delays in starting chemotherapy and decreased the disparities gap between Black and Hispanic patients compared to whites.

Significant disparity in breast cancer mortality rates exists between American Indians (AIs) and whites, according to another study presented. While mortality rates for whites declined from 1990-2009 before the introduction of the ACA, they have remained stagnant for AIs. The study results showed that although early breast cancer diagnosis increased among AIs, the mortality rate remains unaffected. 

Another study during the session, however, showed that among low-income patients, Medicaid expansion did not result in improved time-to-treatment, but it did significantly improve disease stage at diagnosis and uptake of breast conserving surgery. 

These studies all brought into focus the positive impact of policies aimed directly at improving healthcare equity and access. 

“The disparity crisis needs to be approached from many different angles,” Dr. Chavez Mac Gregor said. “I think [access to care] is just a piece of the puzzle, but something that clearly, as researchers and clinicians, we need to start owning and being very vocal about, because giving access really improves the outcomes of our patients. That’s what we all want.”

Looking ahead and involving patients

Karmo emphasized that going forward, research, clinical care, and policy must be tightly woven with the experiences of the patients they ultimately seek to serve.

“Disparities are a civil rights and a human rights issue,” she said. “The solution, however, is in all of our hands. We can change this by enacting anti-racist policies across the globe. And we must have heart-based, vulnerable conversations and have healing on both sides. As our allies, you must agree and believe that being Black should not negate our right to live.”

Read more of BCRF’s SABCS 2020 coverage here.