Who gets ovarian cancer? A woman can inherit an increased risk for this disease, particularly if a "first degree" relative (a mother, sister or daughter) has or had ovarian, breast or colon cancer. In fact, if she has a strong family history of ovarian cancer, she is more likely to develop the disease at an early age (younger than 50). Other risk factors include:
- Ashkenazi (Eastern European) Jewish ethnicity, if the condition has already affected one or more family members
- a defect in the BRCA1 or BRCA2 genes can also increase a woman's risk of developing ovarian cancer by a small percentage (read more about genetic susceptibility at the end of this section)
- a personal history of breast, endometrial or colon cancer
- uninterrupted ovulation caused by infertility or no pregnancies
- a high-fat diet
- starting your periods at a young age, or going through menopause at an older than average age
- use of talcum powder on the genital area — however, evidence supporting this risk factor is conflicting
- Women who use fertility drugs have a higher-than-average risk of developing ovarian cancer.
Of all the risk factors, the most significant is a family history of breast and/or ovarian cancer. However, it's important to keep risk factors in perspective. Most women with risk factors for ovarian cancer will never actually get ovarian cancer. And, most women with ovarian cancer do not have any strong risk factors for the disease. Even with significant risk factors such as family history, the overall chances of getting ovarian cancer are still small. Despite that news, you should always be aware of the risks and, as a preventive measure, consult with your health care professional if you have any risk factors.
Unfortunately, there is no reliable screening tool available for ovarian cancer. If you have any unusual symptoms, consult with your health care professional. Diagnosis starts with a pelvic exam and Pap smear, a relatively painless test that involves taking a scraping of cells from your cervix and examining them under a microscope. Although the Pap doesn't detect ovarian cancer, it may detect cancer cells that have migrated to the uterine cervix from the ovaries or abnormal cells in the uterine cervix. After the Pap smear, other tests your health care professional may perform include:
- CA-125 blood test, which can signal the presence of advanced ovarian cancer; however, experts do not consider this a stand-alone, reliable test. This test is used to determine the level of a tumor marker called CA-125, but is not a screening option because it is unreliable.
Ovarian Cancer Diagnosis (<i>cont'd</i>)
For example, CA-125 levels are normal when ovarian cancer is confined to the ovaries in half of postmenopausal women. Some ovarian cancers do not produce enough CA-125 to cause a positive result. Other benign conditions may increase CA-125 levels. This test is most effective in women who have been treated for ovarian cancer to determine if cancer has recurred.
- abdominal or transvaginal ultrasound, sound waves are used to distinguish fluid-filled cysts from solid ones.
- CAT scan, which produces x-ray images of cross sections of body tissues.
- lower GI series (barium dye enema), which visualizes the bowel on X-ray to detect abnormal areas that may be caused by ovarian cancer or bowel problems.
- intravenous pyelogram, which produces x-rays of the kidneys, bladder and ureters; often, ovarian cysts or tumors can cause pressure on these organs. Before the x-ray is taken, a fluid (a contrast agent) is injected into your veins that will highlight your urinary tract.
If your health care professional suspects ovarian cancer from the tests previously mentioned, the only sure way to diagnose ovarian cancer is through microscopic examination of abnormal fluid or tissue. Although fluid can be obtained by needle aspiration, surgery is usually used to diagnose ovarian cancer and to remove the cancerous growth and any tissue to which the cancer has spread.
If cancer is suspected, the surgeon usually removes the entire affected ovary to ensure that all potentially abnormal areas are removed. A pathologist evaluates the tissue and if cancer is confirmed, typically the second ovary, the uterus and the fallopian tubes are removed.
Inherited Defects for Ovarian Cancer
To date, about five percent of ovarian cancer cases are caused by inherited defects in the BRCA1 and BRCA2 genes. Genes, the pieces of the chemical DNA within your cells that are inherited from your parents, determine many aspects of your body's make-up. Scientists have known for years that genes determine risk for developing a disease like cancer.
Ovarian Cancer Diagnosis (<i>cont'd</i>)
The BRCA1 and BRCA2 genes normally help to prevent cancer by making a protein that keeps cells from growing too much. But if you have a defect in either of these genes — inherited from either parent — they won't prevent the cancer from developing in your ovaries. If you have a defect in the BRCA1 gene, you have a 60 percent chance of getting ovarian cancer. The risks are less with a mutated BRCA2 gene, but still greater than ovarian cancer risk most women face.
Genetic Testing for Ovarian Cancer
Genetic testing for ovarian cancer has raised many questions, both scientific and ethical. Although tests are available to identify the mutations that may predispose you for this cancer, they are not absolutely positive predictors. In addition, many health care professionals are not yet fully educated about the tests that are available, how they are performed and how they are interpreted.
The first step in genetic testing is to examine your family tree, and that's done best with the help of a specially trained genetic counselor. If genetic testing is done properly, it can change lives drastically, both in terms of preventing the onset of ovarian cancer (by taking preventive health care steps) and the psychological impact of knowing you are predisposed to get the disease, or not, regardless of family history. Your health care professional can refer you to a certified genetic counselor.
In a study published in the Feb. 16, 2002 issue of the British medical journal Lancet, researchers described a new computer-based diagnostic test that can accurately distinguish between blood samples from women with ovarian cancer and samples from women without the disease. The 30-minute test, which recognizes patterns of proteins in blood, was also able to identify the disease in its early stages, when treatment is most effective.
Researchers at the National Cancer Institute, the U.S. Food and Drug Administration and Correlogic Systems Inc., a two-year-old Bethesda, MD, firm that developed the test, conducted the preliminary study. It is hoped that with additional and larger clinical studies involving these blood tests, an effective diagnostic test can be developed. It is likely to take several years for this test to become available, if it is determined with further investigation to be safe and effective.
Copyright 2003 National Women's Health Resource Center Inc. (NWHRC).