If oncologist Larry Wickerham ruled the world, every woman would know her chances of getting breast cancer, and those at high risk would be offered a drug to prevent the disease.
This is not a pipe dream, says Wickerham, deputy chair of NRG Oncology, a cooperative research group. The drugs exist; they have been used to treat breast cancer for decades. But only a fraction of eligible women take them for prevention.
Wickerham would like to see the National Cancer Institute run a sustained campaign to educate doctors and the public about so-called chemoprevention of breast cancer, as the National Heart, Lung, and Blood Institute did to promote reduction of cholesterol and blood pressure as a way to prevent heart disease.
But other experts believe there are many other reasons breast cancer chemoprevention is such a hard sell. Among them:
Women are afraid of the potential side effects, and some doctors are reluctant to prescribe drugs to healthy people.
Primary care providers are not trained in breast cancer prevention.
Even if doctors are knowledgeable, they don’t have time in a six-minute office visit to ascertain a patient’s personal preferences, assess her level of risk and discuss the costs and benefits of reducing that risk.
Manufacturers don’t promote drugs for prevention, especially if they are off-patent.
Medical authorities, including the U.S. Preventive Services Task Force, the American Society of Clinical Oncology and the National Institute for Health and Care Excellence in Britain, recommend that women at high risk of breast cancer consider taking one of several anti-estrogen agents that have been shown to cut the incidence of the disease by one-half or more. But only about 1 percent of eligible women do so, according to Jack Cuzick, head of the Centre for Cancer Prevention at Cancer Research U.K.
Breast cancer chemoprevention remains “an enormously underutilized tool,” said Dr. Paul Goss, director of the Dana-Farber/Harvard Cancer Center breast cancer program. “Compared with statins (which reduce cholesterol) or antihypertensive agents (used to treat high blood pressure), the use of breast cancer chemopreventive drugs is very low, and, yet, the safety is as good if not better.”
Advocates of prevention believe the side effects, including bone-thinning, hot flashes and a slightly increased risk of blood clots and uterine cancer, have been exaggerated.
“Patients have unbelievably been oversold on the side effects,” said Dr. Marc Lippman, professor of medicine at the University of Miami. “There is a simple retort: Most women in the randomized trials of chemoprevention drugs could not correctly identify whether they were on the drug or a placebo.”
“The Holy Grail is efficacy with no toxicity,” said Dr. Nancy Davidson, director of the University of Pittsburgh Cancer Institute, “but we don’t have too many drugs that achieve that goal. Statins have their own side effects, but we’ve been able to articulate the benefit.”
“On the whole,” Davidson said, “breast cancer (risk-reduction) drugs have pretty limited toxicity.” But if a patient does have unwanted symptoms, she said, switching to another agent is always an option.