Genetic Testing for Breast Cancer Risk
Every woman carries some risk of developing breast cancer during her lifetime, but some are at more risk than others. Inherited mutations in certain genes are known to raise the breast cancer risk. The most common among these are mutations in the BRCA1 and BRCA2 genes. Although accounting for a relatively small percentage of breast cancers overall, when present, these can greatly increase a woman’s lifetime risk of both breast and ovarian cancer – to as high as 81% and 54%, respectively. Inherited mutations in certain other genes have also been associated with increased risk, though they are less common.
Genetic testing, along with pre-and post-test counseling, are offered at the Saul and Joyce Brandman Breast Center as part of the Wasserman Breast Center Risk Reduction Program or through the GenRISK Adult Genetics Program. Women concerned about their family history can obtain comprehensive risk-assessment services, including recommendations on steps they can take to reduce their level of risk. The programs’ experts can help you interpret the results and put them into context. Genetic counseling and testing can identify high-risk individuals and prevent them from becoming cancer patients.
Who Is at Risk?
Any woman concerned about her breast cancer risk is welcome to make an appointment to discuss the possibility of genetic testing. In particular, those who should consider genetic testing include women who:
- Have a personal history of early-onset breast cancer (diagnosed before the age of 50) or multiple breast cancer diagnoses
- Have a strong family history (multiple breast cancer diagnoses; early age at diagnosis; bilateral disease; male breast cancers; and family members with ovarian cancer or more than one cancer, particularly if they could be hereditary and associated with breast cancer such as pancreatic, thyroid and ovarian
- Women of Eastern European (Ashkenazi) Jewish ancestry, who are more likely to be carriers of alterations in the BRCA genes
How Testing Works
Genetic testing services are available on-site. Before a test is recommended, women are asked discuss their family history and personal history of cancers. If their family history suggests the possibility of a BRCA or other gene mutation, pre-test counseling is offered to help the woman understand the implications of a positive or negative result and the options that are available should they test positive.
For women who have not been diagnosed with cancer, ideally genetic testing will start with a first-degree relative who had breast cancer. If no such relative is alive, though, a test can still be informative.
BRCA testing is typically covered by health insurance policies, and discrimination based on the test results is against the law (Genetic Information Non-Discrimination Act). The genetic tests require that DNA be obtained by either blood draws or saliva samples, and the results are generally ready in two to three weeks.
Implications of Test Results
Identifying a mutation in BRCA or one of the other genes linked to breast cancer risk can have a major impact, and not every at-risk woman chooses to be tested. For those who do, our expert team helps to sort through the implications. Discussing genetic counseling options for patients is part of our weekly multidisciplinary case review meeting.
The advantage of knowing you are at high risk for breast cancer is that it opens the door to options for preventing the disease, reducing the risk, or detecting the disease at an early stage, when treatment is more likely to succeed. Options for patients who test positive for a breast cancer-related gene mutation include both less aggressive approaches, such as lifestyle changes and enhanced screening; and more aggressive methods, including chemoprevention (medications that can reduce risk) and risk-reducing surgeries such as prophylactic removal of the ovaries (oophorectomy) and breast tissue (mastectomy) with breast reconstruction.
Saliva Tests for Individuals Without Significant Risk Factors
Capitalizing on the rapidly advancing field of genomic science, several companies have begun to offer genetics-based saliva or “spit” tests to assess overall breast cancer risk in women even if they have no family history and lack mutations in BRCA or other breast cancer genes. The tests combine patient questionnaires with the results of DNA testing – based on what is known about genetic patterns and breast cancer risk – to assess the likelihood that a woman will develop breast cancer in her lifetime. Such information can be useful for women trying to decide when to begin and how often to go for mammography screening, for example. While Cedars-Sinai does not administer the tests, our experts will provide information and counseling about them and help to interpret the results for patients interested in pursuing them.