Breast Cancer

Breast Cancer Genetics

Were you or a loved one recently diagnosed with breast cancer? Then, you may be curious about whether it runs in the family. That's particularly true if more than one family member has had breast cancer. Like many health conditions, there can be a genetic link, although this appears to be the case in only a small percentage of patients. It's somewhere around 5 to 10%.

Breast Cancer Genetics, Explained

There are two hereditary gene mutations known to increase the risk of developing breast cancer: BRCA1 and BRCA2. For women of average risk about 1 in 8 will develop breast cancer in their lifetimes. For those who have the BRCA1 or BRCA2 genetic mutation, 7 out of 10 will develop breast cancer by the time they are 80 years old.

You can receive the genetic mutation from either your mom or your dad's side of the family. If you have more than one family member on one side of the family — maternal or paternal — who developed breast cancer you might want to consider genetic testing for the BRCA genes.

What is Genetic Testing for Breast Cancer?

Testing for the BRCA gene mutations is done through a simple blood test. If your mom and your dad tested negative previously, you won't have this mutation. However, if they've never been tested and your history and family background meet certain requirements for BRCA gene testing you will meet with a genetic counselor who will talk you through the testing process and what to do with the results.

Are there Pros and Cons of BRCA Gene Testing?

An oncology genetic counselor can help you understand your risk factor and whether genetic testing may be a smart move. Genetic testing has some benefits but also drawbacks, as with any lab test that confirms something.

Pros of cancer genetic testing:

  • You can make behavioral changes to match your risk level.
  • You or your doctor can create a plan for breast cancer screening that would start sooner than women who are at average risk.
  • You can make decisions about whether you'd like to take preventive measures. This can include a prophylactic mastectomy of the breasts. Without breast tissue, it will be harder for breast cancer to develop.
  • Your children will know better if they should or should not get tested now, or in the future.

Cons of cancer genetic testing:

  • Knowing can worsen anxiety or depression. It's important to explore your feelings and speak with a professional in addition to your genetic counselor, if needed.
  • You may not know whether to share your results with family members. Your genetic counselor can assist you with ways you can talk about it with loved ones.
  • If you are still in the family planning stage of your life, a BRCA-positive test results can affect decisions about when to have children. This is because your ovaries are also impacted by the BRCA gene mutations. Your doctor may recommend they are removed to protect you from developing ovarian cancer.

Who Might Benefit from Genetic Testing for Cancer Risk?

Only 1 in 400 people have mutations of the BRCA gene mutation, so it's not standard to perform this genetic test. But if you have a family history on your mother's or your father's side that matches one or more of the below, your breast cancer specialist may recommend it:

  • Anyone with breast cancer detected before age 50
  • Anyone diagnosed with triple-negative breast cancer by age 60
  • Three or more relatives of any gender had breast cancer, ovarian cancer, pancreatic cancer, or aggressive prostate cancer
  • A male had breast cancer at any age
  • A female had ovarian cancer at any age
  • Your heritage is Ashkenazi Jewish combined with any cancer in the family

Other compelling reasons to get tested include:

  • Cancer across multiple generations on a single side of your family
  • History of child or young adult cancers in the family
  • Someone in the family had more than one primary type of cancer

Testing Confirms a BRCA Gene Mutation. Now What?

Stay on Top of Exams and Mammograms

Having a BRCA gene mutation doesn't mean you're definitely going to develop breast cancer, but knowing will make you and your doctors look at anything abnormal that comes up more thoroughly, just to be sure.

Your doctor may also recommend that you start getting mammograms before you usually would begin, and they may add other imaging tests on some of these visits. Those might include an ultrasound or MRI.

If you have the gene mutation, The National Comprehensive Cancer Network (NCCN) recommends:

  • Continuing, or starting, self-exams
  • Every 6-12 months, getting a clinical breast exam starting at age 25
  • Talking with your doctor about the needed frequency for your exams
  • Getting 3D mammograms
  • Considering continuing breast cancer screenings after 75

Preventive Mastectomy Is Something to Consider

This is a very personal discussion, but you may consider a preventive mastectomy or ovary removal if your risk is very high because of a BRCA gene mutation combined with other factors that will be unique to your personal situation. Your genetic counselor can guide you and help you explore how you feel about this. As with all surgeries, there are risks to consider, as well. Breast reconstruction can be cost-prohibitive and may not be fully covered by insurance, so this is something to factor into the decision.

More Lifestyle Changes Proven to Lower Risk

A healthy lifestyle can reduce your risk of developing cancer despite gene mutations, so the NCCN recommends:

  • Eating a healthy varietal diet with plenty of plant-foods (veggies, fruit, nuts, seeds, beans, etc).
  • Managing weight.
  • Meeting or exceeding CDC guidelines for physical activity, at least 150 minutes of moderate activity plus strength training.

American Society of Clinical Oncology further recommends:

  • Keeping alcohol consumption to a minimum or none at all.
  • Choosing to breastfeed, as applicable.
  • Finding natural ways to manage post-menopause side effects to avoid having to take hormones.


Ways to Reduce Your Breast Cancer Risk When You're BRCA Mutation-Positive

women with breast cancer ribbon - ways to reduce breast cancer risk when brca+

Where to Start With Genetic Testing for Breast Cancer

If your family history shows signs of hereditary breast cancer it's a good idea to meeting with a genetic counselor. At Cancer Care Centers of Brevard our genetic counselor will first talk to you see if your history meets the testing guidelines. If it does, you will meet to discuss the results and any possible next steps that may be recommended to help lower the likelihood of breast cancer or ovarian cancer developing in the future.