Reducing the Risk of Ovarian Cancer

Although healthcare providers do not know how to completely prevent the development of ovarian cancer, several strategies reduce the risk of developing the disease. Oral contraceptives, pregnancy, breast-feeding, and removal of the ovaries (i.e., oophorectomy) have been shown to lower the risk of developing ovarian cancer.

You should be familiar with factors that may reduce the risk of developing ovarian cancer and should develop nursing interventions and educational programs to help raise awareness of these means to reduce the risk.

Oral Contraceptives

The risk of developing ovarian cancer decreases 40%–60% with the use of oral contraceptives. A greater reduction in risk is seen as years of usage increase, and the risk does not differ among women who stop oral contraceptives even 10–30 years before. The mechanism for the reduced risk has been attributed to inhibiting ovulation, suppressing gonadotropins, and inducing an apoptotic response. In a recent study evaluating the impact of progestin and estrogen potency on ovarian cancer risk, oral contraceptives with higher progestin dosages were associated with a greater reduction in ovarian cancer risk independent of the estrogen dosage.

Pregnancy and Breast-Feeding

Pregnancy and breast-feeding also help to lower the risk of developing ovarian cancer, presumably in a similar manner to oral contraceptives. Parous women have lower risks of developing ovarian cancer, and the protective effect increases with more parity. Women with one child have a 40% reduced risk; women with five or more children have an 80% reduced risk. Breast-feeding for an average of three to six months is associated with a 30% reduction in risk as compared to women who never breast-fed.

Salpingo-Oophorectomy

Removal of the ovaries and fallopian tubes, salpingo-oophorectomy, often is recommended to women with documented mutations in either the BRCA1 or BRCA2 gene. Recent retrospective and prospective data suggest a clear benefit for prophylactic oophorectomy in mutation carriers after a mutation is identified in a family. Removal of healthy ovarian tissue is thought to reduce the risk of ovarian cancer because the susceptible tissue is unavailable to become cancerous. Removal of ovarian tissue also reduces serum estradiol levels, which may further reduce the risk. Evidence also has suggested that prophylactic oophorectomy reduces the risk of breast cancer in mutation carriers. Prophylactic oophorectomy usually is recommended for women with a known hereditary mutation who are older than 35 or when childbearing is complete. Women who undergo prophylactic bilateral salpingo-oophorectomy still are at risk for developing primary peritoneal cancer, which presents similarly to ovarian cancer, although primary peritoneal cancer is relatively rare.

Other risks associated with prophylactic oophorectomy include surgical complications and, more commonly, early menopause. Premature menopause places women at increased risk for osteoporosis and cardiovascular problems. Women with BRCA1 and BRCA2 mutations may not be candidates for HRT because of a personal history of breast cancer or their significantly elevated risk for developing breast cancer. Because the risks and benefits associated with oophorectomy are significant, women considering this procedure need extensive counseling and education so that they can make informed decisions. Genetic testing may enable women to avoid unnecessary surgery, if it can show that they do not carry the mutation associated with affected family members.

Last updated Nov 26/06