What causes breast cancer? How much do genetics impact the risk for developing breast cancer? Given that 1 in 8 women will develop the disease, these are common questions many women and their families ask. Stephanie Graff, MD, Director of the Breast Cancer Program and Clinical Research at Sarah Cannon Cancer Institute at HCA Midwest Health, answers common questions.
How much do genetics impact the risk for developing breast cancer?
According to the National Cancer Institute, breast and ovarian cancers have been linked to specific mutations in BRCA1 and BRCA2, which are genes that, when functioning normally, produce proteins that help repair damaged DNA and manage a cell's genetic stability. About 15% of genetically mediated breast cancers are caused by mutations in BRCA1 or BRCA2, but many other genetic causes of breast cancer exist. And although we have identified numerous genetic causes of breast cancer, only about 5-10% of breast cancer can be identified as genetically mediated. Other genetic mutations have also been linked to breast cancer, such as PALB2 and TP53.
Dr. Stephanie Graff
What should I do if I am at risk?
If you are at a high risk for breast cancer, talk with your doctor to determine the best screening schedule for you. Women should talk with their physicians regularly starting as early as age 25 about their individualized risk for breast cancer, as higher risk women may benefit from genetic counseling or early screening. Sarah Cannon recommends that women ages 20-40 have a breast exam by their physician or practitioner ever three years, and women ages 40+ should have an annual mammogram.
Healthcare professionals emphasize that there is value in conducting a regular breast self-exam in order to help identify breast cancer in its early stages. Sarah Cannon recommends that women ages 20+ conduct monthly breast self–exams.
What about genetic testing?
The United States Preventive Services Task Force has made the following recommendation for women considering genetic testing for BRCA mutations:
- Women who have a personal or family history of breast, ovarian, tubal, or peritoneal cancer, or an ancestry associated with BRCA 1/2 should be screened to see if their history is associated with an increased risk of carrying a genetic mutation. If so, then genetic counseling is recommended to determine if genetic testing would be useful.
- Women whose personal or family history or ancestry is not associated with increased risk for genetic mutations do not need routine genetic counseling or BRCA testing.
Several different types of genetic testing methods are available to detect genetic mutations some look the mutations in one of the genes and others check for all possible mutations in both genes. The samples for testing typically involve DNA extracted from blood or saliva, and usually take about one month for results.
Sarah Cannon Cancer Institute at HCA Midwest Health offers cancer genetic risk assessments and genetic counseling to women who have concerns about their personal and/or family history of cancer. Patients are provided with personalized information regarding genetic influences, specific cancer risks and targeted screening and prevention options.
If you have questions about genetics and risk for breast cancer, call askSARAH at (844) 482-4812 to speak to a nurse who is specially trained to help with your cancer questions, or visit askSARAHnow.com.