Genetic Testing and Ovarian Cancer
As a genetic counselor specializing in ovarian cancer, I was heartened to learn about a recently approved chemotherapy treatment for women with a type of inherited ovarian cancer. In December, the US. Food and Drug Administration granted accelerated approval of Lynparza (also known as olaparib) for women whose ovarian cancer is caused by an inherited mutation in the BRCA1 or BRCA2 gene. Currently, this treatment is only for women whose cancer has failed to respond to three other types of chemotherapy.
This is an exciting example of how our understanding of the role of genetics in cancer is advancing the field of precision medicine, and bringing hope to women with ovarian cancer or anyone with a cancer that’s resistant to many of our standard treatments.
If you or a close relative has ovarian cancer, you may want to learn more about this treatment option, and consider genetic testing and genetic counseling. Genetic counseling both before and after the test is key.
What Genetic Testing Can Tell You
Genetic testing for ovarian cancer can provide information beyond whether a specific type of chemotherapy might be effective. It can tell you whether your particular type of cancer is hereditary and whether your close relatives, men included, may be at increased risk for developing ovarian cancer or other cancers, and whether they should consider being tested. Data suggest that up to 15 percent of women with ovarian cancer have a BRCA1 or BRCA2 mutation. These genes are associated with a 50 percent to 80 percent lifetime risk of breast cancer and a 20 to 40 percent lifetime risk of ovarian cancer in women, as well as an increased risk for breast cancer in men. These cancer risks are much higher than the risks faced by the general population. Because of this, women with the BRCA gene mutations are advised to begin cancer screenings at an earlier age and have them more often. Some women also consider having surgery to remove their ovaries or their breasts, which significantly lowers their risk of developing cancer. Since men may also inherit a BRCA1 or BRCA2 mutation, genetic testing is important for male relatives to consider as well since their screening would be adjusted if they were found to have the mutation.
Genetic counseling both before and after [genetic testing] is key.
While BRCA1 and BRCA2 mutations are the most common causes of hereditary ovarian cancer, there are less common genetic causes of the disease. In fact, many women with ovarian cancer now choose to have more extensive genetic testing utilizing what is often referred to as multi-gene panel testing. These tests analyze many genes at once and often include the BRCA genes. Multi-gene panels usually include other well-known genes that are less commonly associated with ovarian cancer risk. For some of the genes included in these tests, there are no published guidelines regarding cancer screening so it’s up to your cancer genetics care team to design a screening plan based on the available data.
The Role of Genetic Counseling
The information provided by genetic testing can be extremely useful, but it can also be overwhelming. A genetic counselor can help you decide which genetic test is right for you, guide you through the test results and what they mean for you and your family, and help you consider your options for screening, prevention or treatment.
If you’d like to speak with a genetic counselor, you can locate one in your area using NSGC’s “Find a Genetic Counselor” tool.
Leigha Senter-Jamieson, MS, LGC is a member of the National Society of Genetic Counselors 2015 Board of Directors and is associate professor in the Division of Human Genetics in the Department of Internal Medicine at The Ohio State University