Hereditary Breast Cancer
Most cases of breast cancer are spontaneous and not related to family history. These kinds of cancer are caused by factors encountered after birth such as diet, lifestyle, or environmental exposure to radiation, chemicals or other cancer-causing materials. They cannot be passed down to children from their parents. Roughly 5%–10% are thought to be hereditary, however, which means they are caused by gene mutations that you inherit from a parent.
The most common genes associated with hereditary breast cancer are the tumor suppressor genes, BReast CAncer gene 1 (BRCA1) and BReast CAncer gene 2 (BRCA2). These genes keep breast tissue cells from growing out of control into cancerous tumors, but genetic mutations can interfere with their functions. For instance, triple-negative breast cancer is a type of cancer linked to mutations in the BRCA gene, mainly BRCA1, and this cancer is typically more aggressive and difficult to treat; those at risk should be very carefully monitored.
Genetic testing for the BRCA genes can protect you from other cancers beyond breast cancer. Those include:
- Ovarian cancer
- Fallopian tube or primary peritoneal cancers
- Melanoma
- Pancreatic cancer
- Prostate cancer
- Male breast cancer
Other less common conditions and genetic mutations include the following:
- ATM, CHEK2 and PALB2 genes
- Cowden syndrome, linked to the PTEN gene
- Hereditary diffuse gastric cancer
- Li-Fraumeni syndrome, linked to the TP53 gene
- Peutz-Jeghers syndrome, linked to the STK11 gene
How a Genetic Counselor Can Help
When you have genetic testing, you’ll work with a genetic counselor, who can explain the process before you are tested and help you interpret your results afterward. Because there are many genetic tests available, a genetic counselor can help you understand which option will benefit you most. After all, having BRCA mutations can significantly increase your risk of developing breast cancer, but it does not guarantee you will develop it.
A genetic counselor will review your results and help determine your need for high-risk breast cancer screening. This may involve more frequent screening mammograms, additional imaging studies (such as breast MRI and ultrasound) and monitoring for other types of cancers related to a genetic mutation. They may also speak with you about genetic testing for family members or family planning.
Breast Cancer Risk Factors
Certain genetic and behavioral factors can increase your risk of having breast cancer. Knowing your risk may aid you in making healthy choices and knowing when to seek genetic testing for breast cancer or breast cancer screening.
Genetic risk factors include a personal or family history of:
- Breast cancer diagnosed in someone 50 or younger
- Breast cancer diagnosed in someone of Ashkenazi Jewish ancestry
- Known personal or family history of harmful genetic mutation (such as BRCA1 or BRCA2) on genetic testing for breast cancer
- Male breast cancer
- Multiple primary breast cancers
- Ovarian cancer
- Three or more relatives with breast cancer
- Two relatives with breast cancer if one was younger than 50
- Triple-negative breast cancer, especially if diagnosed younger than 60
In addition to genetic risk factors, you can also be at risk if you smoke, drink alcohol to excess or live a sedentary lifestyle. Additionally, the following risk factors are related to your own personal medical history:
- Advanced age
- Dense breasts
- Early menstruation or late menopause
- Never having children or having the first child later in life
- Not breastfeeding
- Obesity
- Personal history of breast cancer
- Prior abnormal breast biopsy
- Prior chest radiation treatments (particularly if received between ages 10 and 30)
- Use of hormone-replacement therapy with estrogen and progestin in postmenopausal women – there is less risk with estrogen only
Breast Cancer Prevention
There are several things that you can do to reduce your risk of having breast cancer including:
- Breastfeeding your children if possible
- Eating a healthy balanced diet
- Exercising regularly
- Limiting alcohol consumption to one or fewer drinks per day for women and two or fewer drinks per day for men
- Maintaining a healthy weight
- Quitting tobacco
Regular self-breast exams can also help you familiarize yourself with your breasts, so you can discuss changes or concerning symptoms with your doctor. Symptoms of genetic breast cancer are no different than symptoms of other forms of the disease and include:
- A lump in the breast or underarm area
- A change in the size or shape of your breast
- Breast or nipple pain
- Dimpling of the breast that resembles an orange peel
- Nipple discharge other than normal lactation of milk surrounding pregnancy
- Puckering or inversion of the nipple
- Skin changes of the breast or nipple such as redness, sores or dryness
- Swelling or thickening of breast tissue
Early detection and treatment are key to breast cancer survival, so remember to seek medical evaluation if you notice any breast changes or concerning breast symptoms. Follow up with your provider for any recommended clinical breast exams, diagnostics and breast cancer screenings. Be sure to talk to your provider if you believe you have risk factors for hereditary forms of breast cancer.
Keep Your Breasts Healthy
Listen to a podcast about breast health:
The University of Maryland Medical System offers dedicated Breast Health services across Maryland.
- Glen Burnie: UM Baltimore Washington Medical Center
- La Plata | Waldorf: UM Charles Regional Medical Center
- Chestertown | Easton: UM Shore Regional Health
- Bel Air: UM Upper Chesapeake Health
- Baltimore: University of Maryland Medical Center
