Prevention:

The prevention of ovarian cancer is still under investigation. One recent study has looked at the benefits of chemoprevention with a retinoid, a chemical relative of vitamin A, to prevent ovarian cancer. While the results from this study are preliminary, they suggest a potential for chemoprevention in women who are at high-risk. However, most new findings have not been developed into practical methods of prevention.

Meanwhile, there are a number of existing strategies for risk reduction. Some measures may be enacted by the patient, whereas others require surgery. The following strategies may help to reduce risk, but they do not offer guaranteed protection against ovarian cancer.

• Oral Contraceptives—The use of oral contraceptives (OCs; birth control pills) can reduce the risk of ovarian cancer by 40% to 50%. Ovarian cancer risk is significantly decreased after five years of use, although the longer the oral contraceptives are used, the greater the protective benefits. OCs may be particularly important in women who are at high risk of this disease and in carriers of genetic mutations; however, some experts caution that OCs may increase breast cancer risk in women with BRCA mutations.

• Dietary Modification and Exercise—To aid in ovarian cancer prevention, many experts recommend that women eat a low-fat, high-fiber diet and reduce meat and alcohol consumption. Recent studies have shown that following a strict low-fat diet for at least four years can reduce the risk for ovarian cancer. In addition, women are encouraged to exercise three times weekly to maintain a body fat percentage that is within the accepted range. Adults who are 18 years of age or older are considered at risk if the body mass index, or BMI, is greater than 25.

• Pregnancy and Breast Feeding—Although physicians do not advocate making decisions about child-bearing solely for the purpose of reducing ovarian cancer risk, some pregnancy-related statistics are worth noting. Ovarian cancer risk is 30% to 60% lower among women who have been pregnant versus those who have not. In addition, ovarian cancer risk is lower if the first child is born before a woman reaches 30 years of age, and risk continues to decrease with each successive pregnancy. Breast feeding (which begins when estrogen and progesterone levels drop after childbirth and ovulation is suppressed) also appears to offer protection against ovarian cancer.

• Genetic Counseling—Genetic counseling may be advisable if a woman's family history suggests that she may have a genetic mutation(s) associated with increased risk of ovarian cancer. In such cases, the individual should discuss the pros and cons of testing with her physician before undergoing genetic analysis. A person may be comforted to learn that she does not have a mutation, but she may be very disturbed to learn that she does carry the genetic mutation. In spite of this, many high-risk women feel that genetic counseling helps them to make informed decisions about prevention strategies.

• Tubal Ligation—Tubal ligation is a surgical procedure in which the fallopian tubes are ligated, or "tied," to prevent pregnancy. The risk of ovarian cancer is decreased in women who undergo tubal ligation after childbearing, although the mechanism for the protective effect is unknown. Some experts theorize that tubal ligation or hysterectomy -the surgical removal of the womb—may stop carcinogens (cancer-causing agents) from reaching the ovaries after they enter the body through the vagina.

• Ovary Removal—If a woman is over age 40 and hysterectomy is being performed for a noncancerous condition, such as uterine fibroids, she may decide to have her ovaries removed during this operation to lower her risk of ovarian cancer. This procedure—known as prophylactic oophorectomy—is controversial because it causes early menopause in premenopausal women. Prophylactic oophorectomy usually is recommended only for women who have completed their families and have a strong family history of ovarian cancer. Yet it should be noted that removal of the ovaries does not ensure protection in all high-risk patients. Cancers still may form from lining cells within the pelvic cavity, despite the removal of normal ovaries.