Doctors of USC

In the U.S., breast cancer accounts for more than one in four cancer diagnoses among females, making it one of the most common cancers among American women according to the American Cancer Society (ACS). But recent studies have shown that certain lifestyle changes might lower the risk of developing breast cancer.

“Every woman is at risk of developing breast cancer. However, the risk is not equal among all women,” says Dennis R. Holmes, M.D., breast surgeon and researcher at the USC/Norris Comprehensive Cancer Center. “Fortunately, there are several steps women can take to lower their risk.”

Currently, a woman living in the U.S. has more than a 12 percent lifetime risk of developing breast cancer, according to a recent ACS report. But Holmes says that women who exercise for at least 90 minutes each week have significantly lower rates of breast cancer than sedentary women. In addition, exercise helps women obtain or maintain a normal body weight—another factor associated with lower breast cancer risk.

According to Holmes, keeping alcohol consumption to a minimum and quitting smoking also have significant benefits. He also says eating 5 fruits or vegetables a day and regular use of aspirin or ibuprofen has been shown in some studies to reduce the risk of breast cancer. However, he recommends speaking with your doctor before taking either drug regularly, especially if you have a history of heartburn, stomach ulcers or bleeding problems.

On the subject of hormone replacement therapy (HRT), which until recently was used for treating the symptoms of menopause, Holmes says to avoid using HRT. Numerous studies have evaluated the risk of breast cancer in women taking HRT for a prolonged period of time. While the results have been mixed, a report in a spring issue of the New England Journal of Medicine attributed a sharp drop in new breast cancer cases to a national decline in HRT use.

“If you are now taking or considering taking hormone replacement therapy, please ask your primary care physician or gynecologist about alternatives to HRT,” says Holmes. However, if you must use HRT, it is best to use it for less than five years or to use estrogen-only HRT, if possible. Prolonged use of HRT containing both estrogen and progesterone has been more closely linked to an increased risk of breast cancer.

Some women are at a higher risk of developing breast cancer due to personal health and family history factors that cannot be controlled. This includes women who have a family history of breast cancer, lymphoma survivors who received radiation to the chest and those who have a breast cancer gene mutation (BRCA-1 or BRCA-2).

“In addition to practicing the usual risk reduction measures, women who have a higher risk of breast cancer should also consider additional strategies to further reduce their risk,” recommends Holmes.

He says that in addition to more frequent mammograms beginning at age 35, higher-risk women should consider breast MRIs, a new technology that permits detection of very tiny cancers and pre-cancerous changes. Some cancers are even detected by MRIs years before they would be visible on mammograms.

Holmes also notes that anti-estrogen therapies, such as tamoxifen and raloxifene, are highly effective at minimizing the exposure of breast tissue to estrogen and reducing the risk of breast cancer. He says that both medications can be taken daily for up to five years, and the risk reduction benefit continues even after the drugs are stopped.

Additional surgical measures, including removal of both breasts or both ovaries may reduce risk over the lifetime, especially in women with a breast cancer gene mutation, says Holmes. However, he says but there are many steps that can be taken to reduce the risk of breast cancer before turning to surgery.

“Always consult your physician to determine what course of action is the best for you,” Homes says. “Although prevention is our ultimate goal, early detection and treatment of breast cancer are also essential to ensure that women live long and healthy lives. Don’t forget to obtain recommended annual mammograms and annual physical examinations.”

The ACS recommends that women of all ages receive clinical breast exams and mammograms starting at age 40. For more information on breast cancer, visit the American Cancer Society at www.cancer.org.