Approximately 13% of women in the United States will develop breast cancer over the course of their lifetime1. That’s one in eight women.
Further, breast cancer does not target all women equally. For example, Black women have a higher chance of developing breast cancer before the age of 40 than White women2. Black women are also more likely to die from breast cancer than any other race or ethnic group2. Asian, Hispanic, and Native American women have a lower risk of developing and dying from breast cancer3.
A call for collaboration
We must work together as one healthcare ecosystem to reduce incidences, improve health equity, and change the trajectory of breast cancer outcomes for all. We have an opportunity to advance the healthcare system to one that is driven by knowing risk and getting ahead of disease before it may even happen.
Genetic testing is a key tool to support the continuum of patient care, but today it’s an underleveraged and often misunderstood resource. The data-driven medical information derived from genetic testing can provide important personalized insights into the prevention and treatment of breast cancer.
Genetic testing for breast cancer
Approximately 5%-10% of breast cancers are caused by an inherited gene mutation1. Women with a BRCA1 or BRCA2 gene mutation have as much as a 7 in 10 chance of being diagnosed with breast cancer by the time they’re 80 years old3.
On the other hand, women who test negative for high-risk breast cancer gene mutations may still have additional breast cancer risk factors that need to be managed. This kind of information can be assessed using polygenic risk scores (PRS), which is a disease risk assessment for individuals based on their genetic makeup. With PRS, more women will be able to benefit from knowing their genomically informed risk of developing breast cancer and work with their physicians on how to best manage that risk.
In the past, historical barriers and lack of diverse ancestry in genetic databases prevented PRS based risk assessments for breast cancer from being equitable for all women. Genetic markers that are linked to breast cancer in one population do not convey the same risk across all ancestries.
With recent advances from Myriad Genetics and partners within the scientific research community aimed at improving health equity, this PRS disparity has been addressed head on. A study4 published in JCO Precision Oncology highlights the development and validation of a breast cancer PRS for women of all ancestries.
The latest version of the Myriad Genetics MyRisk™ Hereditary Cancer Test with RiskScore®, for instance, now incorporates the PRS enhancement for women of all ancestries to ensure that everyone has access to testing. Results are informed by a combination of genetic markers, clinical and biological variables, personal and family history, and ancestry-specific data.
For patients who have a family history of breast cancer, a gene mutation or a PRS showing high risk, physicians may recommend more frequent screening, such as breast MRI in addition to mammogram, that start at an earlier age. This step alone can support efforts to catch cancer earlier when treatment is more likely to succeed. Hormone reduction options and therapy can also lower breast cancer risk. Some individuals may even choose to have prophylactic mastectomies in order to reduce their chances of developing breast cancer.
For patients who have been diagnosed with breast cancer, genetic testing paired with molecular characterization of the tumor can offer data-driven medical information to better inform personalized treatment decisions. Examples of these tests include Myriad Genetics’ EndoPredict® test for treatment guidance, BRACAnalysis CDx® test for determining whether a breast cancer patient is a good candidate for certain PARP inhibitor therapies, and Precise Tumor™ for targeted chemotherapy matching based on tumor mutations. And for patients’ loved ones, subsequent risk testing can help improve care for their whole family; breast cancer patients found to have a risk-conferring variant can encourage their relatives to get tested to identify others at high risk of developing cancer.
Putting patients at the center
A recent Myriad Genetics survey found that women trust and feel heard by their medical providers, but many expect their medical providers to take the lead on cancer-related conversations. In fact, 76% say they would be more likely to get genetic testing done if it were included as part of their annual physical.
Effective screening tools are only beneficial if they’re being used. The scientific and clinical communities have an important opportunity to raise awareness of the usefulness of hereditary cancer testing and risk assessment for breast cancer. And those in the medical community directly serving patients can help play a key role driving the adoption of genetic testing forward.
Collaboration across the healthcare ecosystem is critical for the advancement of precision medicine. Now is the time to break down barriers and increase the adoption of genetic testing across the continuum of care to improve health outcomes for patients in breast cancer — and ultimately, many other cancers.
1. Breastcancer.org, Breast Cancer Facts and Statistics, https://www.breastcancer.org/facts-statistics
2. American Cancer Society, Key Statistics for Breast Cancer, https://www.cancer.org/cancer/breast-cancer/about/how-common-is-breast-cancer.html
3. American Cancer Society, Breast Cancer Risk Factors You Cannot Change https://www.cancer.org/cancer/breast-cancer/risk-and-prevention/breast-cancer-risk-factors-you-cannot-change.html#:~:text=On%20average%2C%20a%20woman%20with,members%20have%20had%20breast%20cancer.
4. Hughes et al. JCO Precision Oncology 2022 (https://ascopubs.org/doi/abs/10.1200/PO.22.00084