Inherited BRCA mutations

BRCA1 and BRCA2 are genes present in everyone’s body. When they function normally, they help control cell growth by repairing damaged DNA. Everyone inherits one copy of the BRCA1 and BRCA2 genes from each parent.

Sometimes, BRCA1 and BRCA2 genes can develop changes called mutations that increase the risk of breast, ovarian, and other cancers. BRCA1 and BRCA2 mutations can be passed on from a parent.

Below, we discuss BRCA mutations and what testing positive or negative for a mutation means for your treatment, for reducing the risk of future cancers, and for your family.

If you have never been diagnosed with breast cancer and are concerned about your risk, visit At high risk for breast cancer to learn more.

What are inherited BRCA mutations?

BRCA1 and BRCA2 are the genes most commonly linked to hereditary breast cancer. They also increase the risk of:

• Breast cancer developing in the opposite breast
• Ovarian cancer

BRCA mutations are passed down from a parent. If either of your parents has a BRCA mutation, you have a 50% chance of having it, too.

In the United States, about one in 400 people have a harmful BRCA mutation. In some groups of people, the risk of having a mutation may be higher. For example, if you come from an Ashkenazi Jewish background (your family is Jewish and comes from Eastern or Central Europe), your risk is around one in 40.

In the United States, a woman’s average risk of breast cancer is about 13%. Men have close to a 0.1% risk. Carrying a BRCA1 or BRCA2 mutation raises this risk.

• Women who carry a BRCA1 or BRCA2 mutation have a greater than 60% risk of developing breast cancer in their lifetime.
• Men who carry a BRCA1 mutation have a 0.2% to 1.2% risk of developing breast cancer in their lifetime.
• Men who carry a BRCA2 mutation have a 2%-7% risk of developing breast cancer in their lifetime.

Having a BRCA mutation also raises the risk of ovarian cancer.

• BRCA1 mutation carriers have a 39%-58% lifetime risk of ovarian cancer.
• BRCA2 mutation carriers have a 13%-29% lifetime risk of ovarian cancer.

BRCA1 and BRCA2 mutations are also associated with prostate and pancreatic cancer.

Signs breast cancer may be BRCA-related

Certain patterns in your family’s health history may suggest that you or your relatives carry a BRCA1 or BRCA2 mutation linked to breast cancer.

It is possible that your family has an inherited genetic mutation linked to breast cancer if:

• You were under age 50 at diagnosis.
• You were diagnosed with triple-negative breast cancer.
• You had breast cancer in the past and were later diagnosed with a second, new breast cancer.
• You were diagnosed with breast cancer and a strong family history of breast or ovarian cancer.

A strong family history includes:

• Several relatives with breast cancer on the same side of the family
• Any relatives with ovarian cancer; 20% of ovarian cancers are associated with inherited BRCA1 and BRCA2 mutations
• A relative with both breast and ovarian cancer, or with cancer in both breasts
• Any male relative with breast cancer
• A breast or ovarian cancer diagnosis and an Ashkenazi Jewish background; about 2% of people of Ashkenazi (Central-Eastern European) descent have a BRCA mutation

Meeting with a genetic counselor can help you learn more about your personal risk of carrying a BRCA mutation. You can also discuss genetic testing options. Genetic counselors look at your personal breast cancer history as well as your family’s medical history to help guide this decision.

Visit Genetic counseling to learn more.

Who should have testing for an inherited BRCA mutation?

American Society of Clinical Oncology (ASCO) guidelines recommend testing for inherited BRCA1 and BRCA2 genetic mutations if you:

• Are 65 or younger and newly diagnosed or were treated for breast cancer in the past
• Are older than age 65 and:
  • You have a personal or family history of breast cancer that suggests an inherited gene mutation, such as triple-negative breast cancer
  • You are of ancestry that has a known higher incidence of inherited genetic mutations, such as Ashkenazi Jewish ancestry
  • You meet eligibility requirements to take PARP inhibitor breast cancer treatment
• Have a second breast cancer diagnosis that is not a recurrence of a first breast cancer
• Have breast cancer and are assigned male at birth

Read the complete ASCO guidelines for genetic testing in people with breast cancer.

The National Comprehensive Cancer Network (NCCN) recommends BRCA testing for people diagnosed before age 50, or for people diagnosed at any age who:

• May be eligible for PARP inhibitor treatment
• Have been diagnosed with triple-negative breast cancer
• Have been diagnosed with lobular breast cancer and there is a personal or family history of a stomach cancer called diffuse gastric cancer
• Have had more than one breast cancer diagnosis
• Have been diagnosed with male breast cancer
• Are of Ashkenazi Jewish ancestry
• Have a family history that includes close blood relatives with breast cancer at age 50 or younger, male breast cancer, ovarian cancer, pancreatic cancer, or certain prostate cancers

Read the NCCN guidelines for genetic testing in people with breast cancer.

To learn more about the genetic testing process, visit Genetic testing for inherited mutations.

Testing positive for a BRCA mutation

If you’ve been diagnosed with breast cancer and tested positive for an inherited BRCA mutation, you have:

• An increased risk of breast cancer recurrence
• A higher risk of developing a second, new breast cancer
• A higher risk of developing ovarian cancer

Still, a positive result does not mean you will definitely be diagnosed with a new breast cancer or with ovarian cancer. It also does not guarantee others in your family will develop either cancer. Carrying a gene mutation does mean that you have a 50% chance of passing that mutation on to each of your children.

Learning you carry a BRCA mutation can trigger intense emotions, including fear for the future, sadness, and overwhelm. Sharing results with your family can be challenging, especially if you’re the first in your family to have genetic testing.

Visit Sharing your inherited genetic test results to learn more about talking with family, and Where to find support for additional resources.

Positive test results and treatment decisions

Breast cancer treatment decisions are based on:

• Breast cancer stage
• Biomarker test results, which include:
  • Hormone receptor status
  • HER2 status
  • Genomic test results that measure the risk for recurrence in early-stage breast cancer and inform treatment decisions in metastatic disease
• Your overall health history

Regardless of whether you have an inherited BRCA mutation, breast cancer treatment may include:

• Surgery
• Radiation therapy
• Hormonal therapy
• Targeted therapy
• Immunotherapy
• Chemotherapy

But if you test positive for a BRCA mutation, these options may be used in different ways to not only treat the current cancer but help lower your risk of future cancers. There are also targeted therapies that are only available to people who test positive for a BRCA mutation.

Hormonal therapy, chemotherapy, immunotherapy, and targeted therapy

If you tested positive for a BRCA1 or BRCA2 mutation, your treatment may include:

• Hormonal therapy: BRCA2-related breast cancers are more likely to be estrogen receptor-positive than BRCA1-related breast cancers. These cancers are treated with hormonal therapy that blocks or reduces the estrogen that helps the cancer grow. Taking hormonal therapy for five to 10 years has been shown to reduce the risk of recurrence and second breast cancers. Learn more about hormonal therapy.
• Chemotherapy and immunotherapy: Triple-negative breast cancers are more likely to occur in women who carry a BRCA1 mutation. They are treated with chemotherapy and immunotherapy. Learn more about triple-negative breast cancer.
• PARP inhibitors: PARP inhibitors are the only targeted therapy approved specifically for people who test positive for BRCA mutations. You may be eligible for PARP inhibitor treatment if you test positive for BRCA1 or BRCA2, have HER2-negative disease, and have been treated with chemotherapy in the past. Learn more about PARP inhibitors.

Your surgical options also change with a positive BRCA test. Below, we discuss surgery options and how they can help reduce the risk of future breast cancer.

Surgery to reduce risk of recurrence or a new cancer

Surgery is part of breast cancer treatment for almost everyone. Most people diagnosed with breast cancer will have either lumpectomy or mastectomy. Depending on the timing of your genetic tests, you may already have had one of these surgeries.

People who test positive for a BRCA mutation are eligible for two additional surgery options: prophylactic mastectomy and risk-reducing salpingo-oophorectomy (ovary and fallopian tube removal).

Research shows that both options can lower the risk of future breast cancer. Oophorectomy also lowers the risk of ovarian cancer.

Still, choosing to have another surgery is a big decision and can have side effects that impact quality of life. Not everyone chooses these options.

Talk with your doctor about your individual risk level and the benefits and risks of each surgery. Your care team can work with you to decide whether additional surgery is right for you.

Risk-reducing (prophylactic) mastectomy

If you were diagnosed with breast cancer in one breast and have not yet had surgery, you have the option to have the affected breast and the healthy breast removed in a bilateral mastectomy, also called a double mastectomy. Having an unaffected breast removed with a prophylactic mastectomy means there is less breast tissue available to develop a future cancer.

If you were treated with a single mastectomy in the past and have just learned you have a BRCA mutation, talk with your doctor about the potential risk-reducing benefits of mastectomy of the other breast.

People who choose prophylactic mastectomy also have the option to get breast reconstruction.

The decision to have a healthy breast removed is very personal. Mastectomies are major surgeries and may require a good amount of rest and recovery.

Planning, undergoing, and recovering from mastectomy is also an emotional experience. For many people, it can feel overwhelming, and there can be fear, grief, or body image concerns. At the same time, reducing the risk of recurrence or a new cancer by undergoing mastectomy can sometimes bring peace of mind.

If you are considering prophylactic mastectomy, talk with your doctor about your concerns about physical and emotional recovery. Depending on your level of cancer risk, the hormonal status of the cancer, and your comfort, you may be eligible to choose to have more screening tests or to take hormonal therapy instead of undergoing mastectomy.

Risk-reducing salpingo-oophorectomy

BRCA mutations also increase the risk of ovarian cancer. Studies have shown that the ovarian cancer risk is higher in people who carry BRCA1 mutations than in those who carry BRCA2 mutations.

Having the ovaries and fallopian tubes removed in a risk-reducing salpingo-oophorectomy greatly reduces the risk of developing ovarian cancer. Many women with mutations in a BRCA1 or BRCA2 gene choose to have oophorectomy.

Oophorectomy before menopause decreases the risk of a new breast cancer. In hormone receptor-positive disease, it also stops the body from making most of its estrogen, greatly lowering the risk of breast cancer recurrence.

The risk of ovarian cancer increases with age. The National Comprehensive Cancer Network (NCCN) guidelines recommend risk-reducing salpingo-oophorectomy:

• Between ages 35 and 40 for women with BRCA1 mutations
• Between ages 40-45 for women with BRCA2 mutations

Talk with your doctor about the benefits, risks, and timing of oophorectomy before deciding. When the ovaries are removed:

• You can no longer become pregnant naturally.
• Your body goes into surgical menopause, or menopause caused by the surgery.
• Side effects can include menopausal symptoms, such as hot flashes, vaginal dryness, and bone loss.

If you plan to have children in the future, you may decide to wait until later in your life to have an oophorectomy. You can also explore options for preserving your fertility.

Testing negative for a BRCA mutation

If you test negative for a BRCA gene mutation already identified in your family, your result is considered a true negative. This result means you can usually feel confident following the standard breast cancer treatment and follow-up screening in national guidelines.

Some people test negative for BRCA mutations despite a strong personal or family history of breast and ovarian cancer. But they may still be considered high risk. If this is your experience, your doctor may suggest other family members get testing to help better clarify your risk or suggest testing for other inherited genetic mutations.

Talk with your doctor about your concerns, your family history, and what options you have for more frequent screening, risk-reducing surgery, and other measures to lower your risk of a future cancer.

To learn more about test results including variants of uncertain significance (VUS) and what test results mean for your family, visit Understanding genetic test results.