Radical Surgery

By Christine Gorman

For nearly four decades, some women with a family history of breast cancer have been so fearful of possibly having inherited a strong predisposition to the disease that they opted--even though they showed no signs of cancer--to have their breasts surgically removed. But it's impossible to extract every last piece of breast tissue from the upper body; so they were never sure that the procedure, called a bilateral prophylactic mastectomy, would truly help protect them.

Until now. Last week physicians from the Mayo Clinic reported that 639 women, all facing a moderate to high risk of developing breast cancer, underwent prophylactic mastectomies from 1960 to 1993 and reduced their chances of dying from the malignancy at least 90%. The study, published in the New England Journal of Medicine, has received so much attention that it could spark an increase in the number of preventive mastectomies. Currently, according to Dr. Kenneth Kern, a surgical oncologist at the University of Connecticut Health Center and Hartford Hospital, perhaps a few hundred such operations are performed nationwide each year.

But before you or a loved one decide to add to that number, it pays to understand some key statistics--starting with that 90% reduction in deaths. The Mayo investigators derived the figure from statistical models and from the death rate of the patients' sisters, who did not undergo the operation but presumably faced the same cancer risk. The deaths among the untreated sisters led doctors to predict that there should have been 20 deaths from breast cancer in the research subjects. In fact, after the mastectomies, there were only two deaths.

That's good news if you're one of the 18 whose lives were saved--but a high price to pay if you're one of the 619 who underwent radical but ultimately needless surgery.

Most women and even many physicians overestimate a woman's risk of developing breast cancer, says Dr. Barbara Weber, professor of medicine and genetics at the University of Pennsylvania Cancer Center in Philadelphia. For example, everyone has heard that 1 in 9 women develop breast cancer. "That doesn't mean you have a 1 in 9 chance of getting sick tomorrow," she notes. It means that over a lifetime of 85 years, 1 out of 9 women will develop breast cancer. But two-thirds of breast-cancer patients die of something else. In fact, heart disease is by far the biggest killer of women in the U.S., followed by lung cancer.

Even if your mom or grandmother had breast cancer, you're not automatically at greater risk. It depends on their age when they developed the disease. In the U.S., the incidence of breast cancer in women 80 to 85 years old is 15 times as high as it is for women 30 to 34 years old. So if your mother and grandmother had breast cancer in their 70s, you face no more risk than anyone else your age. But if your mother and grandmother had breast cancer before they turned 50, you may have inherited a genetic predisposition toward the disease. That's particularly likely if you also have a family history of ovarian cancer.

Researchers have identified two major genes--dubbed BRAC1 and BRAC2--whose mutations dramatically increase your risk of breast and ovarian cancer. Getting tested for these genetic mutations costs as much as $2,400 for the first test in a family and $400 for subsequent tests and is usually not covered by insurance.

It's easy to make incorrect assumptions about breast cancer. So before you undergo a prophylactic mastectomy or any other preventive therapy for breast cancer, take the time to understand your real risks--as well as any potential benefits.

For facilities that offer genetic counseling near you, call 800-4-CANCER. You can e-mail Christine at gorman@time.com