What are the risks for a family member with a history of genetic breast cancer?

From the Guidelines

If you have a family member with genetic breast cancer, I strongly recommend genetic counseling and testing for yourself to determine your own risk, as this can significantly impact your morbidity, mortality, and quality of life. This typically involves meeting with a genetic counselor who will review your family history and may recommend testing for mutations in genes like BRCA1, BRCA2, PALB2, ATM, CHEK2, and others 1.

Key Considerations

• The risk of inheriting cancer-predisposing mutations follows autosomal dominant inheritance patterns, meaning you have a 50% chance of inheriting the mutation if one parent carries it.
• Even without a mutation, having a first-degree relative with breast cancer approximately doubles your risk, making appropriate screening essential regardless of genetic testing results.
• If you test positive for a high-risk mutation, enhanced screening protocols are recommended, including annual mammograms starting at age 30, breast MRIs, and possibly more frequent clinical breast exams.

Screening and Prevention Strategies

• Some individuals with very high risk may consider preventive medications like tamoxifen or raloxifene, or preventive surgeries such as mastectomy.
• Regular screening for other associated cancers may also be recommended depending on the specific genetic mutation.
• Genetic testing should be preceded by consultation with a genetics counselor or other trained professional to assure full discussion of the risks and benefits and to assure that other genetic syndromes beyond BRCA1 and BRCA2 breast/ovarian syndromes are considered 1.

Guidelines and Recommendations

• The American Cancer Society/American Society of Clinical Oncology breast cancer survivorship care guideline recommends genetic counseling for consideration of testing for hereditary predisposition to gene mutations for breast cancer survivors with certain characteristics, such as a family history of breast or ovarian cancer or cancer in a certain age group and/or cancer type 1.
• The US Preventive Services Task Force recommends that women whose family history is associated with an increased risk for potentially harmful mutations in the BRCA1 or BRCA2 genes be referred for genetic counseling and evaluation for BRCA testing 1.

From the Research

Genetic Breast Cancer Family Member

• A family member with a genetic predisposition to breast cancer, such as a BRCA1 or BRCA2 mutation, is at a higher risk of developing breast cancer 2, 3, 4.
• Women with BRCA mutations should begin breast screening by age 25 or 30, and should consider a highly sensitive breast screening regimen that includes annual magnetic resonance imaging (MRI) and mammography 2, 3.
• The addition of MRI to mammography has been shown to increase the sensitivity of breast cancer detection, but may also decrease the specificity 2.
• Risk-reducing mastectomy (RRM) and risk-reducing salpingo-oophorectomy (RRSO) are options for unaffected BRCA1/2 mutation carriers to reduce their risk of breast and ovarian cancer 3, 4.
• Individuals who test negative for a known family mutation in BRCA1 or BRCA2 may still have a higher risk of breast cancer than the general population, but the evidence is limited 5.
• Universal genetic testing for all breast cancer patients has been proposed, but there are ongoing debates about the accuracy of current guidelines and the costs and benefits of population screening 6.

Screening and Prevention

• Annual MRI and mammography are recommended for women with BRCA mutations 2, 3.
• Novel imaging modalities, such as abbreviated protocol MRI and contrast-enhanced digital mammography, are being investigated for breast cancer screening in high-risk women 3.
• Risk-reducing surgeries, such as prophylactic contralateral mastectomy and bilateral salpingo-oophorectomy, may be considered for women with BRCA mutations 3, 4.
• Chemoprevention with hormonal agents may also be an option for women with BRCA mutations to reduce their risk of breast cancer 4, 6.

Genetic Testing

• Genetic testing for BRCA1 and BRCA2 mutations can distinguish between individuals at high risk of breast cancer and those who are not 5.
• Multigene panel testing may detect additional mutations that could alter clinical management, but there is a lack of evidence on proper procedures and risk management strategies following such testing 6.
• The cost of genetic screening has decreased in recent years, but there are still costs associated with population screening, including genetic counseling 6.