Chemoprevention and Ovarian Cancer
Chemoprevention is the use of medication to reduce risk or prevent diseases such as cancer in healthy people. Some chemoprevention medications may reduce the risk for ovarian cancer. Just how well these drugs perform in high-risk women depends on each woman’s individual level of risk. Because some chemoprevention research may not apply to every person with hereditary cancer risk, when considering your best risk management options, it is important to have a clear a sense of your own risk, as well as the potential benefits and side effects of these medications. A health care team with expertise in managing high-risk patients can help you get a clearer idea of your risk for cancer so you can choose a risk management option that is right for you.
Oral contraceptives are medications used for birth control in women. Studies of women in the general population show use of oral contraceptives lowers the risk for ovarian cancer. One 2004 study of oral contraceptives looked at 451 women with BRCA mutations. Women who took the contraceptives for at least 1 year reduced their risk for ovarian cancer by about 15%, compared with women who didn’t take use the medication. Women who used oral contraceptives for 6 or more years had a 38% reduction in risk for ovarian cancer. Another older study showed an even larger risk reduction in ovarian cancer risk in BRCA1 and BRCA2 carriers who used oral contraceptives. However, a study of ovarian cancer risk in BRCA carriers with one of the three common mutations found in people of Jewish ancestry did not show any risk reduction in women who took oral contraceptives.
Oral contraceptives can have side effects, including a slightly increased risk for blood clots. In addition, one study showed women with BRCA1 mutations who first used oral contraceptives before 1975, before age 30, or who used them for 5 or more years had an increased risk of early-onset breast cancer compared to BRCA 1 carriers who never used the medications. In this study, no increased risk for breast cancer was found in women who carried a BRCA2 mutation. Another study did not find an increased risk for breast cancer with use of more modern low-dose oral contraceptives.
These studies are limited by their small size and the fact they are observational studies only. Their conclusions are noteworthy, but do not prove that taking oral contraceptives actually decreased ovarian cancer risk or increased breast cancer risk. More research is needed in order to understand contraceptive use and cancer risk in BRCA carriers. Oral contraceptives may not be appropriate for all women with BRCA mutations who want to reduce their risk for ovarian cancer. Anyone considering taking oral contraceptives to lower their cancer risk should discuss the benefits, risks and limitations with their health care team and experts in managing high-risk women.
Analgesics are medications used for pain relief. They include many common over-the-counter painkillers called Non-steroidal Anti-inflammatories (NSAIDs), such as aspirin and ibuprofen (Advil, Motrin) and acetaminophen (Tylenol). Research to determine whether these medications decrease ovarian cancer risk produced conflicting results. One study showed a 25% reduction in ovarian cancer risk in women who took aspirin on a regular basis and a 50% ovarian cancer risk reduction in women who took acetaminophen on a regular basis compared to women who did not take either drug. A more recent study showed a similar risk reduction for ovarian cancer in women who took acetaminophen on a regular basis but not women who took aspirin. A third study showed no reduction in ovarian cancer risk in women who took acetaminophen. The Nurses Health Study, a large research effort following 76,821 nurses, found a risk reduction associated with NSAIDs in general but not with aspirin use. None of these studies specifically reviewed ovarian cancer risk in women with BRCA mutations. Because these studies were only observational, they do not prove taking analgesics actually lowered cancer risk.
Certain analgesics in the NSAID category may increase the risk for death from heart disease. A recent clinical trial studying whether Celebrex might reduce the risk for colon polyps was discontinued due to an increase in heart disease and heart-disease related deaths in people who took the medication compared to people who took a placebo. The risk was still low for death by heart disease: about 3% for people who were on the highest dose, and 2% risk for people on the lower dose. However, in that particular study, the benefits of Celebrex were not believed to outweigh the risks.
Clearly more research is needed in order to better understand analgesic use and the risk for ovarian cancer, particularly in BRCA carriers. Anyone considering analgesics to decrease their risk for cancer should discuss the benefits, risks and limitations with their health care team and experts in managing high-risk women.
Fenretinide is a medication related to Vitamin A. Research studies suggest Fenretinide might reduce the risk of several types of cancers. One small study looked at ovarian cancer risk in breast cancer survivors who took this medication to prevent recurrence of their breast cancer. The study found Fenretinide reduced ovarian cancer risk during the 5 years women took it, compared to women who did not take it. The risk-lowering effect did not continue when the medication was stopped. The study also suggested this protective effect against ovarian cancer may be stronger in women with BRCA mutations than women with sporadic breast cancer.
More research is needed. Current clinical trials are studying whether Fenretinide can lower ovarian cancer risk in high-risk women with BRCA mutations. Results from this research will not be available for several years.
This site, produced by the U.S. National Library of Medicine (NLM), provides patients, family members, and members of the public easy and free access to information on clinical studies for a wide range of diseases and conditions.
Disclaimer: Health links are made available for educational purposes only. This information should not be interpreted as medical advice. All health information should be discussed with your health care provider. Please read our full disclaimer for more information.
This site has been made possible by a generous grant from Morphotek.