Overview
BRCA1 and BRCA2 are genes that normally help control cell growth. But an inherited change, called a mutation, in one of these genes makes you much more likely to get breast, ovarian, and some other cancers. BRCA (say "BRAH-kuh") stands for "BReast CAncer."
BRCA gene changes aren't common. Your doctor may talk to you about testing based on your family medical history or your personal medical history. Your doctor may ask you questions, such as if you have family members who had breast or ovarian cancer, if you were diagnosed with breast cancer before age 50, or if you have an Ashkenazi Jewish heritage.
If you are concerned that you may have a BRCA gene change, talk with your doctor.
In the table below, the figures are only rough estimates from research studies of females. These numbers may not apply to you, but they can give you an idea of how high your risk may be.
How does having a BRCA gene change affect your risk? | Breast cancer risk | Ovarian cancer risk |
|---|
Females without a BRCA gene change | About 13 out of 100 will get breast cancer sometime during their lives. | About 1 out of 100 will get ovarian cancer sometime during their lives. |
|---|
Those with BRCA1 gene | About 72 out of 100 will get breast cancer by age 80. | About 44 out of 100 will get ovarian cancer by age 80. |
|---|
Those with BRCA2 gene | About 69 out of 100 will get breast cancer by age 80. | About 17 out of 100 will get ovarian cancer by age 80. |
|---|
Pictures may help you get a better idea of how much a BRCA gene change increases your risk for breast cancer (Figure 1) and ovarian cancer (Figure 2).
Genetic testing can show if you have gene changes that increase your risk for breast cancer and ovarian cancer. Before you have genetic testing, you may want to see a genetic counsellor. Counselling will help you decide about genetic testing. Both testing and counselling are often covered by provincial and private health plans. But check with your health plan to find out for sure.
Ways to reduce cancer risk
Experts know that people who are BRCA-positive are more likely to get breast cancer and ovarian cancer. If you are BRCA-positive, you can take steps to reduce your risk of these cancers.
To help those with BRCA changes, experts did a study of women with BRCA changes to predict how much breast and ovarian cancer risk could be reduced by certain methods. These methods include:
- Having the breasts removed (mastectomy).
- Having the ovaries removed (oophorectomy).
- Having a mammogram and breast MRI every year starting at age 25. These screening tests don't prevent breast cancer. But they can find cancer early, when a cure is most likely.
The results of the study are shown in the tables below.
The study also looked at having the surgeries at different ages. For example, you can see what difference it might make if you keep your breasts and ovaries until you're past your childbearing years. These results are one piece of information you can use as you explore how to lower your cancer risk.
Surgery and screening tests are not your only options. You can also talk to your doctor about medicines, such as tamoxifen. Or you may choose to have no treatment or extra screening.
Women with BRCA1 changes
According to the study, here's how the different prevention methods affect the lifespans of those with BRCA1 changes.
Comparing prevention methods for women with BRCA1 changesPrevention method | Those who live to age 70 after this method |
|---|
No treatment or extra screening. | 53 out of 100 |
Annual breast screening. | 59 out of 100 |
Ovaries removed at age 50. | 61 out of 100 |
Breasts removed at age 40. | 64 out of 100 |
Breasts removed at age 25. | 66 out of 100 |
Ovaries removed at age 40. | 68 out of 100 |
Annual screening + ovaries removed at age 40. | 76 out of 100 |
Annual screening + breasts and ovaries removed at age 40. | 77 out of 100 |
Breasts removed at age 25 + ovaries removed at age 40. | 79 out of 100 |
Women with BRCA2 changes
According to the study, here's how the different prevention methods affect the lifespans of those with BRCA2 changes.
Comparing prevention methods for women with BRCA2 changesPrevention method | Those who live to age 70 after this method |
|---|
No treatment or extra screening. | 71 out of 100 |
Annual screening. | 75 out of 100 |
Ovaries removed at age 50. | 75 out of 100 |
Ovaries removed at age 40. | 77 out of 100 |
Annual screening + breasts removed at age 40. | 78 out of 100 |
Breasts removed at age 25. | 79 out of 100 |
Annual screening + ovaries removed at age 40. | 81 out of 100 |
Annual screening + breasts and ovaries removed at age 40. | 82 out of 100 |
Breasts removed at age 25 + ovaries removed at age 40. | 83 out of 100 |
Deciding about your options
Take some time to think about your options. A genetic counsellor can help you understand how the prevention options affect your cancer risk. Discuss them with your family and close friends. Then you can reach a decision that feels right for you.
Figure 1 - Breast cancer risk
For women with an average risk
slide 1 of 3
slide 1 of 3, For women with an average risk,
Chart based on National Cancer Institute (2020). SEER Cancer Statistics Review 1975–2017. http://seer.cancer.gov/csr/1975_2017/. Accessed July 31, 2020.
On average, about 13 out of 100 women will get breast cancer sometime during their lives. A woman's risk may be higher or lower depending on different factors. Getting older and being female are the two main risk factors linked to breast cancer. Other risks include having a family history of breast cancer, having breast changes or a breast disease that isn't cancer, being white, and drinking alcohol. Hormones such as estrogen may also play a part in some types of breast cancer.
For women who have BRCA1 gene changes
slide 2 of 3
slide 2 of 3, For women who have BRCA1 gene changes,
Chart based on Kuchenbaecker KB, et al. (2017). Risks of breast, ovarian, and contralateral breast cancer for BRCA1 and BRCA2 mutation carriers. JAMA, 317(23): 2402–2416. DOI: 10.1001/jama.2017.7112. Accessed August 5, 2020.
Some women have BRCA1 gene changes. Their risk of getting breast cancer is higher than average. For these women, about 72 out of 100 of them will get breast cancer by age 80.
For women who have BRCA2 gene changes
slide 3 of 3
slide 3 of 3, For women who have BRCA2 gene changes,
Chart based on Kuchenbaecker KB, et al. (2017). Risks of breast, ovarian, and contralateral breast cancer for BRCA1 and BRCA2 mutation carriers. JAMA, 317(23): 2402–2416. DOI: 10.1001/jama.2017.7112. Accessed August 5, 2020.
Some women have BRCA2 gene changes. Their risk of getting breast cancer is higher than average. For these women, about 69 out of 100 of them will get breast cancer by age 80.
Current as of: October 25, 2023
Author: Ignite Healthwise, LLC Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
Figure 2 - Ovarian cancer risk
Women with an average risk
slide 1 of 3
slide 1 of 3, Women with an average risk,
Chart based on National Cancer Institute (2020). SEER Cancer Statistics Review 1975–2017. http://seer.cancer.gov/csr/1975_2017/. Accessed July 31, 2020.
On average, about 1 out of 100 women will get ovarian cancer sometime during their lives. Your risk may be higher or lower depending on different factors. It most often affects women who are past menopause. You may be more likely to get it if others in your family have had it. Also, some women inherit gene changes that increase their chances of getting it.
If you have female pelvic organs, talk to your doctor about your specific risks.
Women who have BRCA1 gene changes
slide 2 of 3
slide 2 of 3, Women who have BRCA1 gene changes,
Chart based on Kuchenbaecker KB, et al. (2017). Risks of breast, ovarian, and contralateral breast cancer for BRCA1 and BRCA2 mutation carriers. JAMA, 317(23): 2402–2416. DOI: 10.1001/jama.2017.7112. Accessed August 5, 2020.
The risk of ovarian cancer is higher than average for women who have BRCA1 gene changes. About 44 out of 100 of them will get ovarian cancer by age 80.
Women who have BRCA2 gene changes
slide 3 of 3
slide 3 of 3, Women who have BRCA2 gene changes,
Chart based on Kuchenbaecker KB, et al. (2017). Risks of breast, ovarian, and contralateral breast cancer for BRCA1 and BRCA2 mutation carriers. JAMA, 317(23): 2402–2416. DOI: 10.1001/jama.2017.7112. Accessed August 5, 2020.
The risk of ovarian cancer is also higher than average for women who have BRCA2 gene changes. About 17 out of 100 of them will get ovarian cancer by age 80.
Current as of: October 25, 2023
Author: Ignite Healthwise, LLC Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
