90% of women miscalculated their risk for breast cancer
More than 90% of women inaccurately perceived their breast cancer risk, according to results of a large-scale, multicenter survey presented at the Breast Cancer Symposium.
Recent US Preventive Services Task Force guidelines recommend women who are most likely to develop primary breast cancer and are at low risk for side effects begin risk-reducing treatment with tamoxifen or raloxifene (Evista, Eli Lilly). However, the fact that most women either under- or overestimate their breast cancer risk may limit clinicians’ abilities to tailor personalized treatment plans, according to researchers.
“It’s imperative that women understand their risk for breast cancer because, if they have a good knowledge of where they stand, they can avail themselves and a doctor could set up a treatment plan for them that includes early detection modalities,” researcher Jonathan D. Herman, MD, an obstetrician and gynecologist at Hofstra North Shore-LIJ Medical School in New Hyde Park, N.Y., said during a press conference. “For the high-risk patient, the tailored plan will lead to early detection through MRI or ultrasound, and we can take measures such as chemoprevention, leading to reduced risks and better outcomes.”
The analysis by Herman and colleagues included 9,873 women who underwent breast cancer screening at 21 centers on Long Island, N.Y. The women, who ranged in age from 35 to 70 years, completed surveys that asked them to gauge their risk for developing breast cancer within the next 5 years, as well as during the course of their lives assuming a 90-year life expectancy. Researchers also collected information about patient demographics and their breast cancer risk factors, including personal or family history and the findings of any prior biopsies.
Herman and colleagues used the NCI’s Breast Cancer Risk Assessment Tool to estimate each participant’s risk and compared those findings with survey responses. When survey estimates differed from researcher-calculated risks by more than 10%, they were deemed inaccurate.
Overall, 9.4% of participants correctly perceived their risk, whereas 44.7% underestimated their risk and 45.9% overestimated their risk.
“When women underestimate their risk for breast cancer, they probably don’t get the necessary or most accurate treatment,” Herman said. “When women overestimate their risk, we think that they’re worrying about getting breast cancer more than they really have to.”
Based on researcher calculations, most of the patients in the study (75%) had a 5% to 15% risk for breast cancer. Five percent of patients had a 20% to 25% lifetime risk, and another 5% had greater than 25% risk.
However, more than one-quarter of survey respondents (26.1%) predicted their risk for breast cancer was greater than 50%, whereas about one-fifth (25.1%) of respondents believed their risk was nonexistent.
“Women are surrounded by breast cancer awareness messages through pink ribbons, walks and other campaigns, yet our study shows that fewer than 1 in 10 women have an accurate understanding of their breast cancer risk,” Herman said in a press release. “That means that our education messaging is far off, and we should change the way breast cancer awareness is being presented.”
When stratified by race, the results showed non-Hispanic white women were most likely to overestimate their breast cancer risk. Among whites, 51.3% overestimated their risk, 38.6% underestimated their risk and 10.2% made an accurate estimate.
The majority of Asian (58.8%), black (57.6%) and Hispanic participants (50.4%) underestimated their risks.
Differences between those groups were statistically significant, but the difference was not important because the overall understanding of breast cancer risks among participants in all subgroups was low, Herman said.
Women — with help from their primary care physicians and gynecologists — must take steps to ensure they accurately understand their breast cancer risk, Herman and colleagues concluded. Free tools that help assess a woman’s breast cancer risk are available to physicians online, and health insurance providers will cover costs associated with additional screening for women who can document they are at increased breast cancer risk.It takes a minute to go through the questions, but that minute is not being spent often enough in doctors’ offices,” Herman said in a press release. “Women should be aware of their breast cancer risk number, just as they know their blood pressure, cholesterol and BMI numbers.”
Disclosure: The researchers report no relevant financial disclosures.
For more information:
Herman JD. Abstract #4. Presented at: Breast Cancer Symposium; Sept. 7-9, 2013; San Francisco.