The average woman in the United States has about a 1 in 8, or about 12%, risk of developing breast cancer in her lifetime. Women who have an abnormal BRCA1 or BRCA2 gene (or both) can have up to an 80% risk of being diagnosed with breast cancer during their lifetimes. Breast cancers associated with an abnormal BRCA1 or BRCA2 gene tend to develop in younger women and occur more often in both breasts than cancers in women without these abnormal genes.
Personal Cancer History
Your personal cancer history also affects your risk. Any of these events in your personal history could be a sign of hereditary breast or ovarian cancer:
- You have blood relatives (grandmothers, mother, sisters, aunts) on either your mother’s or father’s side of the family who had breast cancer diagnosed before age 50.
- There is both breast and ovarian cancer on the same side of the family or in a single individual.
- There are other cancers in your family in addition to breast, such as prostate, melanoma, pancreatic, stomach, uterine, thyroid, colon, and/or sarcoma.
- You are African American and have been diagnosed with breast cancer at age 35 or younger.
- A man in your family has had breast cancer.
- There is a known abnormal breast cancer gene in your family.
Know Your Family History
It is important to know your family history. You should investigate who has had breast cancer on both your mother’s and father’s side of the family. A family history of any of the following may be a sign of hereditary cancer:
A Relative With:
- Bilateral breast cancer (cancer in both breasts)
- Breast and ovarian cancer
- Male breast cancer
- A BRCA mutation
Two Relatives With:
- Breast cancer (one before age 50)
- Ovarian cancer at any age
- One with breast cancer and one with ovarian cancer
Three Relatives With:
- Breast cancer at any age
If you are concerned about your family history, you should meet with a genetic counselor or a qualified healthcare professional.
Important things to know:
- Most breast and ovarian cancers are not caused by these genetic changes
- Most people don’t need to be tested for the BRCA 1/2 gene
- If there is a strong family history of breast and/or ovarian cancer, meeting with a genetic counselor may be helpful
- Health insurance may not always cover the cost of testing
- Genetic testing is most useful if first performed on someone in the family who has had breast or ovarian cancer