If you have an increased risk of developing ovarian cancer, your doctor may periodically order a blood test that has shown some usefulness in finding epithelial ovarian cancer. It measures a substance in the blood called CA-125. Unfortunately, this test is not very specific. Levels of CA-125 may be elevated in women who do not have ovarian cancer, or they may be low in women who do.
Another test that is sometimes used to screen high-risk women is transvaginal sonography. This involves putting a small instrument in the vagina to image the ovaries with sound waves. No radiation is involved.
Many cases of familial epithelial ovarian cancer that result from inherited abnormalities in the gene (genetic mutations) can be identified by genetic testing. Inherited mutations of the BRCA1 and BRCA2 genes account for about 5 percent to 10 percent of breast and ovarian cancers. In most people, these genes make proteins that keep cells from growing abnormally. If a woman has inherited a mutated gene from either parent, this cancer-preventing protein is less effective.
About half of women with inherited BRCA1 mutations will develop breast and/or ovarian cancer by the age of 70. A mutation in the BRCA2 gene also increases the risk of developing ovarian cancer, but not as much as the BRCA1 mutation. In addition, a rare type of colon cancer that runs in families, hereditary nonpolyposis colon cancer, somewhat increases the risk for developing ovarian cancer.
Deciding whether to undergo genetic testing is a complicated process. A genetic counselor can walk you through the process and make sure that you consider all the arguments for and against testing.
Taking birth control pills may decrease ovarian cancer in women at high risk — possibly reducing the cancer risk by half. However, their use may increase the risk of breast cancer in women with the BRCA1 or BRCA2 mutation, so additional research is needed.
Sometimes high-risk women elect to have both ovaries removed before cancer occurs. This surgery (prophylactic oophorectomy) is usually recommended only for very high-risk women who have completed their child-bearing, because it causes premature menopause. Women who undergo prophylactic oophorectomy may still occasionally develop a primary peritoneal cancer (cancer of the tissue lining the abdomen), which can behave like ovarian cancer.
Reviewed by health care specialists at UCSF Medical Center.
This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.
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