Cancer of the ovary (ovarian cancer) is the seventh most common cancer and the fifth leading cause of cancer death among women in the United States. It also causes more deaths than any other cancer of the female reproductive system.1 About 1 in every 71 women in the United States will develop ovarian cancer.2 Two out of three cases occur in women over the age of 55, but it also affects younger women.2 Women of white race are more likely than other groups to get ovarian cancer.3
The sooner ovarian cancer is found and treated, the better a woman's chance for recovery. But ovarian cancer is hard to detect early; less than 20% of cases are diagnosed before it has spread from the original site.2
Although there is currently no recommended screening test for ovarian cancer for the general population, recent research suggests that certain symptoms may indicate the presence of the disease even at an early stage.3
QUESTIONS & ANSWERS ABOUT OVARIAN CANCER
What are ovaries and what do they do?
Ovaries are part of a woman's reproductive system. A woman has two ovaries located in the pelvis, one on each side of the uterus. The ovaries produce eggs (ova) and also are the main source of the female hormones estrogen and progesterone. These hormones regulate the menstrual cycle and pregnancy, and control the development of female body characteristics. When a woman goes through her "change of life" (menopause), her ovaries stop releasing eggs and make far lower levels of hormones.
What is ovarian cancer?
Ovarian cancer is a cancer that forms in the tissues of the ovary. The most common type of ovarian cancer starts in the "epithelial" cells on the surface of the ovary. Less common types of ovarian cancer develop from the egg-forming "germ" cells or from the supporting tissue (stroma) of the ovary.
While the exact causes of ovarian cancer are not known, certain "risk factors" seem to increase a woman's chance of getting this disease.
- Age. Most women are over age 55 when diagnosed with ovarian cancer.
- Family history of cancer. Women who have a mother, daughter, or sister with ovarian cancer have an increased risk of the disease. Also, women with a family history of cancer of the breast, uterus, colon, or rectum may also have an increased risk of ovarian cancer. However, only about 10% of all ovarian cancers can be linked to a family history of the disease.3 If several women in a family have ovarian or breast cancer, especially at a young age, this is considered a strong family history.
If you have a strong family history of ovarian or breast cancer, you may wish to talk to a genetic counselor. The counselor may suggest genetic testing for you and the women in your family. Genetic tests can sometimes show the presence of specific genetic changes in genes called BRCA1 and BRCA2 that increase the risk of ovarian cancer. Read more about Genetic Testing for Hereditary Breast and Ovarian Cancer
- Personal history of cancer. Women who have had cancer of the breast, uterus, colon, or rectum have a higher risk of ovarian cancer. Women who have had breast cancer are twice as likely to develop ovarian cancer.
- Never pregnant. Older women who have never been pregnant have an increased risk of ovarian cancer.
- Hormone replacement therapy. Some studies have suggested that women who still have ovaries and take estrogen by itself (without progesterone) for 10 or more years may have an increased risk of ovarian cancer.
Having a risk factor does not mean that you will get ovarian cancer. Most women who have risk factors do not get ovarian cancer, whereas women with no risk factors except their age may get the disease. If you think you may be at risk of ovarian cancer, talk with your doctor.
Ask your relatives if any women in your family have had ovarian, breast, or colon cancer. If the answer is "yes," be sure to tell your gynecologist or your primary care provider. Depending on your risk, you may need to be checked every 6 months. If you are at very high risk, are over 35 years of age, or do not plan to have any more children, your doctor may advise you to have your ovaries surgically removed before they show any signs of disease.
Does anything protect against ovarian cancer?
Women who have had at least one child, and women who breast-feed are less likely to get ovarian cancer. Using oral contraceptives (birth control pills) also lowers risk. These factors reduce the number of times a woman ovulates during her lifetime, which may decrease the risk of developing ovarian cancer. Women considered at high risk due to personal or family history should consult regularly with a specialist and discuss strategies for prevention and early detection.
What are the symptoms of ovarian cancer?
Ovarian cancer used to be called "the silent killer" because it caused no symptoms until it had advanced too far for successful treatment. Experts now say, however, that some symptoms of ovarian cancer occur even early in the disease process.3
- Feeling bloated;
- Pelvic or abdominal pain;
- Trouble eating or feeling full quickly;
- Gas or indigestion that can't otherwise be explained;
- Urinary symptoms, such as urgent or frequent feelings of needing to go.
These symptoms may be caused by other health problems, but if they occur on most days and last for more than a few weeks, you should see your doctor promptly.
Other symptoms of ovarian cancer (which also can be caused by other conditions) include:
- Nausea or loss of appetite;
- Shortness of breath or difficulty breathing;
- Pain during sexual intercourse;
- Change in menstrual flow;
- Feeling tired;
- Slight fever;
- Frequent constipation and weight change.
Is there a screening test for ovarian cancer?
There is currently no recommended method of screening for ovarian cancer in the general population. If you have ovarian cancer in your family history, or if you are having symptoms, your doctor may perform a combination of tests. They include:
- A recto-vaginal pelvic exam. The doctor can feel if there is any mass or growth in the abdomen. The doctor will insert one finger into your vagina and one finger into your rectum and press down on your abdomen with the other hand.
- A CA-125 blood test. CA-125 is a substance often found in the blood and urine of women with ovarian cancer. However, other, non-cancerous conditions can also cause an increase in CA-125, so a cancer diagnosis cannot be made from this test alone.
- A trans-vaginal sonogram (also called an ultrasound). This painless test uses sound waves to check for growths inside the pelvic area.
- A biopsy. A biopsy is the removal of tissue or fluid to look for cancer cells. Based on the results of the blood tests and ultrasound, your doctor may suggest surgery to remove tissue and fluid from the pelvis and abdomen. Surgery is usually needed to diagnose ovarian cancer.