Strategies for women at an increased risk for breast cancer
Although the majority of women who are diagnosed with breast cancer do not have a family history of the disease, approximately 5% to 10% of breast cancers occur in women with inherited gene mutations. These women are considered to be at an increased risk of developing breast and ovarian cancers during their lives.
The most common inherited mutations that increase breast cancer risk occur in the BRCA1 and BRCA2 genes. The lifetime risk of developing breast cancer in the general population is 13%. But for people with mutations to the BRCA1 and BRCA2 genes, that risk increases to 55% to 72% and 45% to 69% lifetime risk respectively. There are other less common inherited mutations and hereditary syndromes that also increase risk, including:
- Inherited mutations in PALB2 gene (associated with a 35% increase in risk), CHEK2 gene, ATM gene, BARD1 gene, CDH1 gene, NF1 gene, PTEN gene, RAD51C and RAD51D genes, STK11 gene, and TP53 gene
- Lynch syndrome
- Cowden syndrome
- Li-Fraumeni syndrome
- Peutz-Jeghers syndrome
- Ataxia telangiectasia
- Hereditary diffuse gastric cancer
Beyond mutations and hereditary syndromes, there are other factors associated with an increased breast cancer risk. These include:
- Family history of breast cancer, especially cancer diagnosed at a younger age
- Receiving chest radiation between the ages of 10 and 30
- Being diagnosed by biopsy with lobular carcinoma in situ or atypical hyperplasia of the breast
- Personal history of breast cancer
- Male relative with breast cancer
- Being of Ashkenazi Jewish ancestry
Building a risk management strategy
If you have an increased breast cancer risk or are concerned about your potential risk, talk with your gynecologist or women’s health provider. Your provider can use a breast cancer risk assessment tool like the Gail model, which uses information about your age, menstruation and reproductive history, race and ethnicity, and family and personal breast cancer history to assess overall risk. Your provider also may suggest genetic testing and counseling to get a clearer picture of your risk.
Another risk management tool is earlier and more frequent screening for breast cancer. Depending on what type of gene mutation is found and/or the youngest age that a family member was diagnosed with breast cancer, your provider may recommend screening mammograms or MRI every year beginning when you’re 25 to 40 rather than the recommendation for women at average risk of starting screening at 45. Women who are at increased risk should also have a comprehensive clinical breast exam every six to twelve months.
Medication (called chemoprevention) and prophylactic mastectomy and ovary removal can lower the risk of developing breast cancer in women at increased risk. The medications used to lower risk include tamoxifen and raloxifene. These medications are selective estrogen receptor modulators and reduce the risk of developing estrogen receptor-positive breast cancers. They interfere with estrogen’s ability to stimulate breast cancer cell growth. Tamoxifen is also used to treat breast cancer.
Aromatase inhibitors, which lower estrogen levels in the body, may be another medication option for women who have already gone through menopause. Although they are only FDA approved to treat breast cancer not to prevent it, clinical trials have shown this type of drug does effectively reduce risk.
Women who are considering prophylactic surgery should seek a second opinion to help them make an informed decision about the risks and benefits of this risk reduction approach. A health advisor can connect you with experienced specialists for an in-person or virtual second opinion and can also provide you with evidence-based information on the full spectrum of risk reduction strategies.