In recent years, breast cancer prevention campaigns — with pleas to get screened regularly and watch for lumps and other warning signs — have saved many lives.
Yet they may also have an unintended consequence, new research suggests: Many women have become so hyperaware of the possibility of breast cancer that they overestimate their personal risk. Other studies have found that women who have or had breast cancer are likely to overestimate their risk of getting cancer in the opposite, healthy breast.
Women overestimating their breast cancer risk is very common, says Joanne Mortimer, M.D., director of Women's Cancers Program at City of Hope Comprehensive Cancer Center in Duarte, Calif. She has heard women from all walks of life and education levels peg their risk much higher than it actually is.
"Even smart, educated women freak out [that] they are going to get breast cancer," she says, even when their actual risk is low. This is understandable especially if you’ve had cancer before, she adds. The inundation of breast cancer messages — and not just during Breast Cancer Awareness Month — doesn’t help either.
Miscalculating your breast cancer risk
The general female population has a 12 percent risk, or a 1 in 8 chance, of getting breast cancer in a lifetime, and that risk increases with age. However, this risk increases to about 20 percent if a woman's mother had breast cancer, says Jonathan D. Herman, M.D., an obstetrician-gynecologist at Hofstra North Shore Long Island Jewish School of Medicine. And when a woman tests positive for the high-risk BRCA 1 or 2 gene mutations (mutations known to elevate breast cancer probability), the risk skyrockets to 70 percent or higher, depending on the type of mutation, experts say.
For women trying to estimate their own probability of getting breast cancer, a new study finds that a fair number incorrectly estimate their actual risk. Herman and his team polled more than 9,000 women, ages 35 to 70, asking them to assess their risk of getting breast cancer. Researchers then computed the women’s actual risk.
Fewer than 10 percent of study subjects accurately gauged their risk, both over the next five years and their lifetimes, Herman reported at the 2013 American Society for Clinical Oncology (ASCO) Breast Cancer Symposium. About 44 percent of participants underestimated their risk, while about 46 percent overestimated. White women and Hispanic women were more likely to overestimate than were Asian or African-American women, but Herman can't explain why.
However, women age 40 and younger who have had breast cancer before are likely to overestimate the risk of getting cancer in the opposite healthy breast, sometimes spurring them to have it removed, found another study published in Annals of Internal Medicine journal. When researchers surveyed 123 young breast cancer survivors, they found that those who did not have the high-risk BRCA gene mutations thought their risk of getting breast cancer in the opposite breast in the next five years was 10 percent when it was actually 2 percent. It’s understandable why, but better communication about risks is needed, they conclude.
Gauging your actual risk
Assessing your personal risk of breast cancer should begin with a discussion with your doctor, the experts agree. Before you go, gather your family history details: which relatives had breast cancer and when? It’s a good idea to go back at least two generations — parents and grandparents on both sides — says Herman. Physicians rely on your information about family history and factor in your own medical history to help them assess your risk.
Once you and your physician recognize your actual risk, together you can decide on the best breast cancer screening plan for you — when to begin, what it should include and how often tests should be repeated.
Take the next steps
Beyond regular screening for breast cancer, you can work on a breast-healthy lifestyle:
- Maintaining a healthy weight and staying active have both been linked with lower breast cancer risk.
- Limiting your own exposure to radiation and environmental pollutants helps, too.
- Finally, avoiding cigarettes or alcohol abuse can help decrease your risks of breast cancer — even more excellent reasons to quit.