Hereditary Breast and Ovarian Cancer
Breast cancer is the most common type of cancer among women in the United States, with more than 200,000 new cases diagnosed each year. In fact, about 1 in 8 women will develop breast cancer sometime during her lifetime.
Ovarian cancer is less common, with over 23,000 diagnoses each year in the United States. Around 1 in 55 women will develop ovarian cancer during her lifetime.
Breast and/or Ovarian Cancer in Families
Some kinds of cancer, including breast and ovarian, can run in families. Although most cases are not hereditary, about 5-10% of breast and ovarian cancer cases may be hereditary, associated with an inheritance of a single genetic alteration.
Breast and Ovarian Cancer Genes
Mutations in two genes, discovered in the 1990s, are involved in the majority of families with early onset breast and/or ovarian cancer. These genes are called BRCA1 and BRCA2. ("BR" stands for breast and "CA" stands for cancer. The numbers "1" and "2" represent the order in which they were found.)
Hereditary Breast and Ovarian Cancer Risks
Everyone has BRCA1 and BRCA2 genes, but in some individuals there is an alteration, or change, in one of these genes. For women who have inherited an alteration in either BRCA1 or BRCA2 the risk of developing breast cancer by the age of 70 is approximately 50-85%. (This compares to a risk of 7% by age 70 for women in the general population.) The lifetime ovarian cancer risk for women with a BRCA1 or BRCA2 alteration ranges between 10-45% (compared to a 1-2% risk by age 70 for women in the general population).
Am I at an Increased Risk for Carrying an Alteration in BRCA1 or BRCA2?
- Have you had a diagnosis of breast cancer before age 40?
- Have you had bilateral breast cancer or have you had breast cancer and ovarian cancer?
- Have you been diagnosed with breast cancer or ovarian cancer?
- Do you have several close relatives who have had breast cancer (especially before age 50) and/or ovarian cancer?
- Do you have any male relatives who have had breast cancer?
- Does your family have Ashkenazi Jewish ancestry and have you and/or a close relative been diagnosed with breast cancer and/or ovarian cancer?
- Do you have a blood relative who has had a positive genetic test for an inherited alteration in one of the genes associated with hereditary breast/ovarian cancer syndrome, BRCA1 or BRCA2?
If you answered "YES" to any of these questions, you may be at an increased risk for carrying an alteration in one of the genes associated with hereditary breast/ovarian cancer syndrome.
Is Cancer Genetic Testing Right for Me?
Genetic testing for alterations in the breast/ovarian cancer susceptibility genes is now available. The decision to undergo genetic testing is a very personal one and there are many issues to consider before making this decision. Cancer risk assessment and counseling is an important step before making the decision to pursue genetic testing. If you are concerned about your risk of cancer, cancer risk counseling can help you better understand your risks and the options available to you and your family.
Vanderbilt-Ingram Cancer Center
Family Cancer Risk Service
Vanderbilt Health-One Hundred Oaks
719 Thompson Lane Suite 25107
Nashville, TN 37204
or toll-free (877) 688-7555