A study suggests that fewer than 10% of women accurately estimate their risk of breast cancer. Women were just as likely to overestimate their risk as they were to underestimate it.
The research was presented at a media briefing on Sept. 3, 2013 for the 2013 Breast Cancer Symposium. Read the abstract of “Women’s understanding of personal breast cancer risk: Does ethnicity matter?”
Very few studies have compared a woman’s assessment of her own risk of breast cancer with their actual risk.
The study involved 9,873 women who were having a screening mammogram done at 21 facilities in Long Island, New York. The women were between 35 and 70 years old. The researchers had the women answer a 25-question survey that asked about:
- demographics (age, ethnicity, etc.)
- estimates of their own breast cancer risk by age 90
- personal risk factors (family history of breast cancer, benign breast disease, pregnancy history, etc.)
The researchers found that only 9.4% (707 women) accurately estimated their risk of breast cancer:
- 44.7% (3,359 women) underestimated their risk
- 45.9% (3,454 women) overestimated their risk
When the researchers looked at the results by ethnicity, they found that:
- 8.7% of black women accurately estimated their risk; 57.6% underestimated their risk and 33.7% overestimated their risk
- 10.2% of Asian women accurately estimated their risk; 58.8% underestimated their risk and 31% overestimated their risk
- 8.9% of Hispanic women accurately estimated their risk; 50.4% underestimated their risk and 40.8% overestimated their risk
- 10.2% of white women accurately estimated their risk; 38.6% underestimated their risk and 51.3% overestimated their risk
The results of this study are concerning. Women who don’t know their true risk of breast cancer may not be making the best decisions about prevention strategies.
Women who believe their risk is lower than it actually is may not consider taking medicine to help keep that risk as low as it can be. Women who believe their risk is higher than it actually is may take medicine or other more aggressive steps, such as protective surgery, that isn’t necessary.
Right now, most doctors use some form of the Gail model, a standard breast cancer risk assessment tool, to calculate breast cancer risk. The Gail model assesses breast cancer risk based on a series of personal health questions that you and your doctor answer together. The questions ask about risk factors such as age, child-bearing history, family history of breast cancer, and breast biopsy results. Some more recent versions of the Gail model also ask about alcohol use, menopausal status, and body mass index. The result is a Gail score, which estimates the risk of developing invasive breast cancer in the next 5 years.
While the Gail score is an estimate, it does take into account your personal and family history of breast cancer and is considered to be accurate.
For more information on breast cancer risk and how it’s calculated, visit the Breastcancer.org Understanding Breast Cancer Risk pages in the Lower Your Risk section.