On Cancer: Understanding Your Risk for Breast and Ovarian Cancer

Actress Angelina Jolie ignited a national dialogue on the topic of breast cancer risk and genetic testing with a May 14 op-ed in the New York Times in which she describes her experience in choosing to undergo a preventive double mastectomy after she learned that she carries a mutation in a gene called BRCA1.

The inherited gene mutation is associated with an increased risk of breast and ovarian cancer among people of Eastern European Jewish ancestry. It was first discovered in the mid-1990s. Soon after that, a Memorial Sloan-Kettering research team led by medical oncologist Kenneth Offit identified a mutation in another gene, BRCA2, which is also associated with breast and ovarian cancer.

Today, testing is available for mutations in BRCA2, as well as BRCA1 and other genes that have been linked to an increased risk for breast and ovarian cancer. Women can use the results of such genetic tests to make informed decisions – such as whether to surgically remove the breasts (preventive mastectomy) or ovaries (preventive oophorectomy) – to reduce their cancer risk. 

In an interview, Dr. Offit, Chief of the Clinical Genetics Service, notes that there have been great strides in prevention and early detection of breast cancer since the BRCA1 and BRCA2 mutations were identified. He encourages women and their families to take these factors into consideration when weighing their options.

Q: Who should undergo genetic testing for breast cancer?

It’s very important that women speak to their physicians if they have a personal history of breast cancer or close relatives who have had breast, ovarian, or prostate cancer, or some other types of cancer. Other strong risk factors include having had breast cancer at an early age (before age 50), having both breast and ovarian cancer, having a male relative with breast cancer, and being of Eastern European Jewish ancestry. In addition all women with a personal history of ovarian cancer regardless of their family history should have BRCA testing.

While a significant number of women with breast cancer have a family history of the disease, only a small number may be advised to get genetic testing. Only about 5 to 10 percent of women with breast cancer will have an inherited risk of breast cancer due to BRCA mutations.  

Q: What is involved in getting tested?

Genetic testing is not just a blood test. It’s a process of genetic counseling that often involves the family. We like to see individuals with their sisters, with their mothers, their significant others – both as a support and to enable women and their family members to make mutual decisions about screening and prevention.

Women meet with a genetic counselor to review all the options available should a test turn out to be positive, and also visit with a doctor to go over their family history of cancer and other risk factors in more detail. Only at that point is the actual test given (if a woman chooses to have it). Results take a few weeks to come back.

Q: What kind of information does genetic testing provide to women and their families?

If a woman tests positive for a BRCA mutation, she is not only at increased risk for breast cancer, but at increased risk for ovarian cancer as well. In fact, while the BRCA test is named after breast cancer, it is the ovarian cancer risk that we pay close attention to because we don’t have a means to screen for ovarian cancer to find it early, when it’s potentially curable.

When we first started doing genetic testing we were very concerned about the negative impact that results might have. But we have found that genetic testing is in fact a very empowering experience both for the woman and her family, as there are now proven means for prevention and detection of some of the associated cancers. 

Q: If a genetic test shows that a woman has an increased risk for breast or ovarian cancer, what are her options?

There are basically three options available upon testing positive for BRCA mutations. Surgery is one of them, and it’s the most effective means of breast cancer prevention. And while the surgical option for breast cancer is just that – an option – we strongly recommend surgical removal of the ovaries to reduce the risk of ovarian cancer for women who no longer expect to have children.

Doctors at Memorial Sloan-Kettering and other hospitals now have a very powerful means of screening for cancerous changes in the breast with magnetic resonance imaging, or MRI, which is more precise than mammography in finding early breast cancers. While most women in the United States choose screening over surgery this is a discussion that needs to be individualized.

In addition, we can offer preventive treatment with drugs such as tamoxifen that for some women can cut the risk for breast cancer in half. 

Q: Do you foresee any new advances in genetic testing for breast or ovarian cancer?

Up until now, we have only been able to tell a woman who tests positive for a BRCA mutation that her risk for developing cancer ranges from 40 to 90 percent. Women have had to decide how to manage their cancer risk based on this average.

But over the last several years, researchers at Memorial Sloan-Kettering and elsewhere have discovered that there are genetic variations that will allow us to more closely pinpoint risk, and determine whether a woman’s risk is closer to 40 percent or closer to 90 percent. We hope to make these more-precise testing options available to women over the coming year as part of our continued research. This research will become available over the next 12 months.

To make an appointment with our Clinical Genetics Service, call 646-888-4050.

To make an appointment with one of our breast cancer specialists, call 646-497-9064.