Health Letter, December 2016
By Michael Carome, M.D.
On Sept. 7, 2016, the Food and Drug Administration (FDA) warned women and their doctors not to use widely marketed ovarian cancer screening tests because results of the tests are often inaccurate. The agency is especially concerned that use of these tests can lead some women who may have ovarian cancer to delay effective treatment and spur others who do not have cancer to undergo unnecessary diagnostic procedures and surgery.
Ovarian cancer: Statistics and risk factors
Ovarian cancer is the second-most-common form of cancer of the female reproductive system and the leading cause of gynecologic cancer deaths in the U.S. It accounts for about 3 percent of all cancers in women in the U.S. and is the fifth-leading cause of all cancer-related deaths among women.According to the American Cancer Society, each year approximately 22,000 women in the U.S. are diagnosed with ovarian cancer and about 14,000 die from the disease.
Ovarian cancer occurs most often in older women; the median age at the time of diagnosis is 63.White women have a higher risk for the disease than women of other racial and ethnic backgrounds. Other risk factors for ovarian cancer include:
- A family history of ovarian cancer
- A family or personal history of breast cancer
- Certain genetic mutations, such as the BRCA1 and BRCA2 genes
- Polycystic ovarian syndrome
- Postmenopausal estrogen-only hormonal replacement therapy
Factors associated with a decreased ovarian cancer risk include multiple pregnancies, use of birth control pills and breastfeeding.
When ovarian cancer is found at an early stage — before it has spread beyond the ovaries — the prognosis is very good, with an overall five-year survival rate of more than 90 percent. Unfortunately, because early-stage ovarian cancer usually does not cause significant symptoms, most women with the disease — approximately 80 percent — already have advanced disease that extends beyond the ovaries by the time they are diagnosed. In fact, in about 60 percent of cases, the cancer already has spread to other organs, such as the intestines, liver, spleen, lungs or kidneys.
The desire to detect more cases of ovarian cancer at an earlier, more easily treatable stage has driven the marketing of ovarian cancer screening tests. One of the most commonly used screening tests for the disease has been a blood test for CA-125.
CA-125 is a protein in the blood that is elevated in many women who have been diagnosed with ovarian cancer. The test can be helpful for monitoring a patient’s response to treatment: If the treatment is working, the level of CA-125 often will go down.
According to the FDA, numerous companies have promoted tests purported to screen for and detect ovarian cancer. In its Sept. 7 warning, the agency called out one company in particular: U.K.-based Abcodia. The company recently began marketing a test called Risk of Ovarian Cancer Algorithm (ROCA), which is based on repeated measurements of CA-125, to screen women at high risk for ovarian cancer. The company has aggressively marketed the product in five states since 2015 and plans to sell it nationwide by the end of 2016.
The FDA’s warning
In its Sept. 7 warning, the FDA noted that, despite extensive research and multiple published studies, there are “currently no screening tests for ovarian cancer that are sensitive enough to reliably screen for ovarian cancer without a high number of inaccurate results.” The FDA specifically emphasized that the available data do not support Abcodia’s claims that the ROCA test can increase the chances of survival by successfully detecting ovarian cancer before symptoms appear.
The FDA is worried that women and their doctors may be misled by such claims and make incorrect treatment decisions based on inaccurate results. For example, some women undergoing these tests may receive results suggesting they have ovarian cancer, even though no cancer is present. Such false-positive test results can lead to additional unnecessary diagnostic procedures and surgery, which could result in serious complications. On the other hand, other women undergoing screening may have negative results, suggesting that no ovarian cancer is present, when in fact they do have cancer. These false-negative test results may lead the women to delay or not seek surgery or other appropriate treatment for the disease.
Finally, the FDA warns that use of these unproven screening tests may be particularly harmful to women with the greatest risk of developing ovarian cancer because of genetic mutations or a family history of the disease. These women and their doctors may fail to take preventive actions to reduce their future risk of cancer if they rely on results from unreliable screening tests showing no cancer.
The FDA’s recommendations
The FDA offered the following recommendations to women, including those at high risk of developing ovarian cancer:
- Be aware that there is currently no safe and effective ovarian cancer screening test.
- Do not rely on ovarian cancer screening test results to make health or treatment decisions.
- Talk to your doctor about ways to reduce your risk of developing ovarian cancer, especially if you have a family history of ovarian cancer or have the BRCA1 or BRCA2 genetic mutations.
 National Cancer Institute. A snapshot of ovarian cancer. November 5, 2014. https://www.cancer.gov/research/progress/snapshots/ovarian. Accessed October 22, 2016.
 American Cancer Society. Ovarian cancer: What are the key statistics about ovarian cancer? February 4, 2016. http://www.cancer.org/cancer/ovariancancer/detailedguide/ovarian-cancer-key-statistics. Accessed October 22, 2016.
 American Cancer Society. Ovarian cancer: Survival rates for ovarian cancer, by stage. February 4, 2016 http://www.cancer.org/cancer/ovariancancer/detailedguide/ovarian-cancer-survival-rates. Accessed October 22, 2016.
 American Cancer Society. Ovarian cancer: Can ovarian cancer be found early? February 4, 2016.http://www.cancer.org/cancer/ovariancancer/detailedguide/ovarian-cancer-detection. Accessed October 22, 2016.
 Kaplan S. FDA warns against widely used ovarian cancer screening test. STAT. September 7, 2016. https://www.statnews.com/2016/09/07/ovarian-cancer- screening-test/. Accessed October 22, 2016.