The Role of Genetics in Breast Cancer: Do I Need Genetic Testing?

If you've recently had a positive breast cancer screening mammogram or are worried about symptoms, it's natural to feel overwhelmed and full of questions. One question that may arise is whether genetics play a role in your situation. Understanding the role of genetics in breast cancer can help you make informed decisions about next steps and your health. Here's what you need to know about genetic testing, how mutations affect breast cancer risk, and whether testing makes sense for you.

What is Genetic Testing?

Genetic testing identifies changes in your genes that might increase your risk of breast cancer. While most breast cancers aren't caused by inherited genes, some women carry genetic mutations that significantly raise their risk. These are called hereditary genetic mutations.

Common Genetic Mutations Linked to Breast Cancer

Two of the most well-known genetic mutation slinked to breast cancer are BRCA1 and BRCA2. These mutations are passed down from either parent and can significantly increase a woman’s risk of breast cancer.

BRCA1 and BRCA2 Mutations: These are the most commonly known genetic mutations linked to breast cancer. Women who inherit a BRCA1 or BRCA2mutation have a much higher risk of developing breast cancer—up to 72% by age80 according to the American Cancer Society (ACS). These mutation scan also increase the risk of other cancers, such as ovarian cancer.

Other Mutations: Less common genetic mutations in genes likeTP53 and PALB2 can also increase breast cancer risk, however mutations in these genes are less common and have a lower overall impact on breast cancer risk compared to BRCA mutations.

Do You Need Genetic Testing?

The Mayo Clinic highlights that genetic testing isn't necessary for everyone with a positive mammogram or abnormal symptoms. Consider discussing genetic testing with your doctor if you answer "yes" to any of these questions:

• Family History: Do you have close family members (parent, sibling, or child) who had breast cancer, especially before age 50?
• Multiple Family Members Affected: Do multiple people in your family have breast or ovarian cancer?
• Ethnicity: Are you of Ashkenazi Jewish descent? This group has a higher likelihood of carrying BRCA mutations.
• Personal History: Have you been diagnosed with breast cancer before age 50, or do you have a personal history of ovarian cancer?

Genetic counseling is often a good first step if you're considering genetic testing. A genetic counselor can help you understand your family’s history, assess your risks, and decide if genetic testing is right for you.

Understanding Your Test Results

If you undergo genetic testing, there are a few possible outcomes. Understanding what these results mean can help you make informed decisions about your health and future care.

Genetic test results fall into three categories:

• Positive Result: You have a mutation that increases your cancer risk. This doesn't mean you're guaranteed to develop cancer, but your risk is higher. With this knowledge, you and your doctor can create a plan to manage your risk.
• Negative Result: No harmful mutations were found in the genes tested. While this can be a relief, it's important to remember that a negative result doesn’t mean you are free from risk. According to the NIH, 90-95% of breast cancers occur in women without known genetic mutations. Regular breast health screenings and staying aware of any changes in your body remain important.
• Variant of Uncertain Significance (VUS): In some cases, the test results may show a genetic change, but its significance is not clear. This is known as a VUS. In these cases, the change may or may not affect cancer risk, and further testing or monitoring may be needed.

What to Do With Your Results

If you test positive for a genetic mutation, it can feel overwhelming, but remember that this information is powerful. It allows you to take steps to manage your health proactively. Some options include:

• Increased Surveillance: Women with a BRCA mutation may begin mammograms and breast MRIs at a younger age and more frequently to catch potential cancer early.
• Preventive Medications: Some high-risk women choose medications like tamoxifen to lower their risk.
• Preventive Surgery: Some women with high genetic risk consider mastectomy (removal of breasts) or oophorectomy (removal of ovaries) to significantly reduce cancer risk.

Work closely with your healthcare team to make decisions that align with your health needs and personal preferences. Your situation is unique, and you deserve a plan tailored to you.

Expert Guidance, Your Decision

Genetic testing can be a helpful tool in understanding your breast cancer risk and can provide you with valuable information to help guide your healthcare decisions. While mutations like BRCA1 and BRCA2 increase risk, a positive result doesn't guarantee you'll develop cancer—it simply means you need a more proactive approach to protect your health.

If you're considering genetic testing, you can talk to a doctor or a genetic counselor. Your Defiant Health team can also help you understand what testing can and cannot tell you, and guide you toward the right decision for your situation. You don't have to figure this out alone.