Fact vs. fiction: The truth about genetic testing

Whether you’re at high risk, newly diagnosed, or being treated for breast cancer, you may want to talk with your health care team about genetic testing for inherited mutations. Meanwhile, there are several misconceptions people have about genetic testing; here are seven common myths, as well as the facts behind them:

Myth 1: Only young women with breast cancer should get genetic testing.

Fact: The National Comprehensive Cancer Network (NCCN) recommends genetic testing for inherited mutations after a breast cancer diagnosis for women and those assigned female at birth of all ages whose families are Ashkenazi Jewish (from Central and Eastern Europe); men of all ages; and people of all ages with certain subtypes of breast cancer or with at least one close relative with male breast cancer.

Myth 2: Only people with triple-negative breast cancer need genetic testing for an inherited mutation.

Fact: Testing isn't just for people with TNBC. NCCN recommends genetic testing for an inherited mutation for people diagnosed with lobular breast cancers, which are commonly hormone receptor-positive, who have a personal or family history of diffuse gastric cancer.

Myth 3: Genetic testing doesn’t offer information that can be used to make treatment decisions.

Fact: Testing positive for a BRCA1 or BRCA2 gene mutation can influence treatment options for both surgery and medicine, whether you’ve been diagnosed with breast cancer or not – and regardless of the cancer stage.

Surgery: Testing positive for either BRCA gene mutation (among others), even without a breast cancer diagnosis, means you may benefit from a prophylactic, or preventive, mastectomy. With a positive result after a diagnosis, you could choose to have the unaffected (healthy) breast removed preventively.

BRCA1/2 are also associated with a high risk for ovarian cancer, so many doctors recommend women with either gene mutation have a preventive oophorectomy – surgery to remove the ovaries. (NCCN provides testing criteria for other susceptibility genes, including pancreatic, prostate, and colorectal cancers.)

Medicine: Targeted therapies called PARP inhibitors can be used to treat hereditary breast cancers. One of these drugs, olaparib (Lynparza), is FDA approved for people diagnosed with certain breast cancers, such as metastatic and early-stage HER2-negative breast cancer – who have a BRCA1 or BRCA2 mutation. In metastatic breast cancer, another PARP inhibitor, talazoparib (Talzenna) is also available.

Myth 4: Only white people need to be tested.

Fact: People of color can and do test positive for hereditary gene mutations. The racial disparities that exist in cancer research and care also exist for genetic testing for inherited mutations. While research hasn't clearly proved racial differences in the frequency of inherited breast cancer gene mutations, Black women are less likely to be referred for genetic testing than white women, and Hispanic women are less likely to be referred than non-Hispanic women.

Myth 5: Health insurance won’t cover genetic counseling or testing.

Fact: Insurance plans must cover genetic counseling for women at increased risk for breast cancer; many will cover testing if a doctor recommends it. Consult with your doctor about your options.

Myth 6: If my health insurance company knows I have a genetic mutation, I will be uninsurable.

Fact: It is illegal for insurance companies to deny coverage to people who have tested positive for genetic mutations, per the Genetic Information Nondiscrimination Act.

Myth 7: Since I can get an at-home test, I don’t need to talk with a genetic counselor.

Fact: A genetic counselor can help you decide if testing is a good choice for you and can help you understand the relevance and limitations of the results. Results from at-home tests often don’t give enough information for most people to know what they mean (even when they come back negative) or to puzzle through next steps – if any – to take. Counselors are trained to understand the results and help make other choices or treatment decisions based on test findings.

The field of genetic testing for inherited mutations has progressed significantly over the years. Scientists continue to further their understanding of genetic predisposition, and they hope to find better, more targeted ways to prevent, identify, and treat cancer in people who carry the genetic mutations that increase risk.

For more information:

• https://www.lbbc.org/about-breast-cancer/testing/genetics-and-family-risk
• https://www.nccn.org/professionals/physician_gls/pdf/genetics_bop.pdf
• https://www.cancer.org/cancer/breast-cancer/risk-and-prevention/preventive-surgery-to-reduce-breast-cancer-risk.html
• https://health.gov/myhealthfinder/doctor-visits/talking-doctor/genetic-testing-learn-about-your-risk-breast-and-ovarian-cancer-questions-doctor
• https://sharsheret.org/brcagenetics/
• https://www.facingourrisk.org/

Did you know that breast cancer and prostate cancer can be linked? Get the facts #GetScreenedTogether here.