From the Guidelines
Genetic testing for breast cancer, specifically BRCA mutation analysis, is recommended for certain high-risk individuals, including those with a strong family history of breast or ovarian cancer, those of Ashkenazi Jewish descent, or individuals with a personal history of breast cancer diagnosed at a young age (under 65 years). According to the most recent guidelines from the American Society of Clinical Oncology (ASCO) and the Society of Surgical Oncology 1, BRCA1/2 mutation testing should be offered to all newly diagnosed patients with breast cancer ≤65 years and select patients >65 years based on personal history, family history, ancestry, or eligibility for poly(ADP-ribose) polymerase (PARP) inhibitor therapy. The testing typically involves a blood draw or saliva sample, and if a harmful genetic mutation is found, options for increased surveillance, preventive medications, or risk-reducing surgeries may be discussed. The reason for selective testing is that harmful mutations in breast cancer genes are relatively rare in the general population. Testing everyone would lead to many false positives and unnecessary anxiety. However, in high-risk groups, identifying mutations can significantly impact medical management and potentially save lives through early detection or prevention strategies. Before pursuing testing, genetic counseling is strongly recommended to understand the implications, limitations, and potential outcomes of the results. Key points to consider:
- BRCA1/2 testing should be offered to women who develop a second primary cancer in the ipsilateral or contralateral breast.
- Testing for high-penetrance cancer susceptibility genes beyond BRCA1/2 should be offered to those with supportive family histories.
- Patients should be provided enough pretest information for informed consent, and those with pathogenic variants should receive individualized post-test counseling.
- Variants of uncertain significance should not impact management, and patients with such variants should be followed for reclassification.
From the Research
Genetic Testing for Breast Cancer
- Genetic testing for breast cancer, specifically BRCA (Breast Cancer Gene) mutation analysis, is recommended for certain individuals 2, 3.
- The American Society of Breast Surgeons recommends genetic testing to assess hereditary risk for breast cancer, including BRCA1/BRCA2 and PALB2, for patients with a personal history of breast cancer 2.
- Genetic testing should also be made available to patients without a history of breast cancer who meet National Comprehensive Cancer Network guidelines 2.
- Family history is a key component of breast cancer risk assessment, and appropriate breast cancer screening and risk reduction management plans rely on an accurate assessment of a patient's family history 4.
Recommendations for Genetic Testing
- Genetic testing should be offered to each patient with breast cancer (newly diagnosed or with a personal history) 2.
- Patients who had genetic testing previously may benefit from updated testing 2.
- Variants of uncertain significance are not clinically actionable, and these patients should be managed based on their individual risk factors 2.
- Women with a strong family history of breast cancer are more likely to be aware of genetic testing for breast cancer risk assessment 5.
Importance of Family History
- Family history provides clues as to the likelihood of a hereditary breast cancer syndrome and the need for a cancer genetics referral 4.
- Having a mother or sister with breast cancer is reported as being extremely or very important by nearly all respondents, regardless of family history 5.
- Perceived lifetime risk for developing breast cancer is associated with family history, but the perception of the lifetime risk for breast cancer is often higher than the true risk 5.