What your DNA reveals and why it’s worth knowing
By Shivani Nazareth, MS, CGC, and Kaylene Ready, MS, CGC
Ovarian cancer is often dubbed as the “silent killer” of women. The symptoms are vague—including bloating, fatigue, irregular bleeding, frequent urination, and back pain1 —making it difficult to diagnose early. By way of comparison, detection and treatment of breast cancer has progressed tremendously. This is demonstrated by the five-year relative survival rate, which is 90 percent for breast cancer2 and only 46 percent for ovarian cancer.3 Women may dislike the experience of mammography, but it remains an excellent screen for breast cancer. Unfortunately, there is not a similarly successful screen for ovarian cancer. In fact, the US Food and Drug Administration issued a safety watch4 advising women to be wary of tests that are marketed as ovarian cancer screens.
The good news is only about 1 in 75 women5 will develop ovarian cancer in her lifetime—that’s a 1.3 percent risk. If we flip the number, there is a greater than 98 percent chance that a woman will not develop ovarian cancer in her lifetime. Your individual risk could be significantly higher, however, if you have a family history or a genetic predisposition.
For example, women with Lynch syndrome have up to a 12 percent risk of ovarian cancer,6 and women with a BRCA1 or BRCA2 mutation have up to a 50 percent risk of ovarian cancer.7 You might recall actor Angelina Jolie talking about her decision to undergo preventive surgery to reduce her ovarian cancer risk.8 She did so because she inherited a BRCA1 mutation from her mother. Many women opt for similar preventive surgeries when they learn of an inherited high risk of ovarian cancer, but it’s important to know that there are also less invasive options, like taking birth control pills.9 The path is different for each woman, but having access to the information allows you to be proactive.
If you’re wondering whether DNA testing for ovarian cancer makes sense for you, your family history is a good place to start gathering information. If you notice that several family members have colon, uterine, or ovarian cancers, that could indicate Lynch syndrome; if you notice a family history of breast and ovarian cancers, that could suggest a BRCA1 or BRCA2 mutation. Keep in mind these are just clues; if you have a small family or there are not many women in it, a pattern may be hard to see. In fact, more than half the women9 with a genetic predisposition to ovarian cancer are the first women in their families to develop the cancer.
If you are interested in DNA testing for ovarian cancer after learning about your family history, speak with your physician or find a genetic counselor through the National Society of Genetic Counselors (nsgc.org). Advocacy groups such as FORCE, Bright Pink, and the National Ovarian Cancer Coalition are also good resources; they offer support and education to help women make choices that are right for their personal circumstances.
Shivani Nazareth is the director of medical affairs at Counsyl, a DNA-testing and genetic-counseling service. She worked as a clinical genetic counselor for more than 10 years in New York City, most recently at Weill Cornell Medical College. Shivani obtained her graduate degree from the Icahn School of Medicine at Mount Sinai in New York City and currently serves on the National Society of Genetic Counselors’ Public Policy Committee.
Kaylene Ready is the clinical product director of cancer screening at Counsyl, a DNA-testing and genetic-counseling service. Prior to joining Counsyl, she worked at MD Anderson Cancer Center. Kaylene obtained her graduate degree from the University of Texas Graduate School of Biomedical Sciences and currently serves on the Board of Directors of the National Society of Genetic Counselors.
2 Cancer Stat Facts: Female Breast Cancer. National Cancer Institute website. Available at: https://seer.cancer.gov/statfacts/html/breast.html. Accessed January 14, 2017.
4 Ovarian Cancer Screening Tests: Safety Communication—FDA Recommends against Use. US Food and Drug Administration website. Available at: http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm519540.htm. Accessed January 14, 2017.
5 NOCC Delivers Hard Hitting Message for September National Ovarian Cancer Month. National Ovarian Cancer Coalition website. Available at: http://www.ovarian.org/component/content/article/35-news/372-nocc-delivers-hard-hitting-message-for-september-national-ovarian-cancer-month. Accessed January 14, 2017.
7 Hereditary Breast and Ovarian Cancer. Cancer.Net website. Available at: http://www.cancer.net/cancer-types/hereditary-breast-and-ovarian-cancer. Accessed January 14, 2017.
8 Pitt AJ. Angelina Jolie Pitt: Diary of a Surgery. New York Times. March 24, 2015. Available at: http://www.nytimes.com/2015/03/24/opinion/angelina-jolie-pitt-diary-of-a-surgery.html?_r=1. Accessed January 14, 2017.
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