The majority of women residing on Long Island, New York who underwent mammography screening and responded to a large-scale survey either underestimated or overestimated their risk of developing breast cancer, according to research presented at the 2013 Breast Cancer Symposium that took place last September in San Francisco, California.
At the same time, 4 in 10 of the women surveyed said they had never discussed their personal breast cancer risk with a physician. To the authors' knowledge, this study is the first to identify a knowledge gap in women, and they hope the findings will encourage more physicians to perform breast cancer risk assessments of their patients.
Study author Jonathan Herman, MD, an obstetrician/gynecologist at Hofstra North Shore-LIJ School of Medicine at Hofstra University in Hempstead, New York, says that the medical community needs to change its educational messaging about breast cancer awareness to help women better understand their personal breast cancer risk. That understanding is important for women to make good decisions regarding screening and prevention, he adds.
Women who have a 5-year risk of greater than 1.66% and those with a greater than 20% lifetime risk of developing breast cancer may benefit from chemoprevention with tamoxifen, raloxifene, or anastrozole or from surveillance such as magnetic resonance imaging screening. Meanwhile, women who overestimate their risk may experience unnecessary anxiety, testing, and interventions.
Dr. Herman and his colleagues surveyed 9873 women between the ages of 35 years and 70 years who underwent mammography screening at 21 centers on Long Island. They asked them to estimate their own risk of developing cancer over the following 5 years and over their lifetime. They also asked for information concerning patient demographics (race/ethnicity, religious affiliation, education, marital status, household income, and health insurance status), breast cancer risk factors (age at first birth, personal and family history of breast cancer, breast cancer biopsy findings), and any prior breast cancer risk assessments and discussions. Many of these questions were selected from the National Cancer Institute Breast Cancer Risk Assessment Tool.
Researchers then compared a woman's actual lifetime risk with her own subjective risk estimate. Of the group, 707 women (9.4%) accurately estimated their risk, whereas 3359 (44.7%) underestimated their risk and 3454 (45.9%) overestimated their risk. White women tended to overestimate their risk whereas African American, Asian, and Hispanic women were more likely to underestimate their risk. The overall understanding of breast cancer risk among all groups was low, which indicates that such understanding may be even lower in the general population because the women in the study were already concerned about their risk.
Investigators plan a future study to survey primary care providers regarding their perceptions of women's knowledge of their breast cancer risk and how often they discuss the risk with their patients.