The Breast Cancer Risk Assessment Tool (the Gail model) was designed by researchers at the National Cancer Institute and the National Surgical Adjuvant Breast and Bowel Project. The tool calculates a woman's risk of developing breast cancer within the next five years and within her lifetime (up to age 90). This tool takes into account seven key risk factors for breast cancer.
- Personal history of breast cancer, ductal carcinoma in situ (DCIS) or lobular carcinoma in situ (LCIS)
- Age
- Age at first period
- Age at first birth
- Family history of breast cancer (mother, sister or daughter)
- Number of prior breast biopsies
- Number of breast biopsies that showed atypical hyperplasia
- Race/ethnicity
Women who have a five-year risk of 1.67 percent or higher (of the risk of an average 60-year-old woman) are classified as "high-risk". These criteria (a five-year risk of 1.67 percent or higher) are the cut-off for FDA guidelines on tamoxifen and raloxifene use for breast cancer prevention.
Limitations of the Breast Cancer Risk Assessment Tool
The Breast Cancer Risk Assessment Tool has some limitations. It is not clear what a risk calculated by the model means for an individual woman. For instance, if the model gives you a five-year risk of 1.7 percent, keep in mind that this is a group average, based on women who have similar risk factors. The model can predict the number of women in a group who will get breast cancer. However, it cannot predict which of these women will be diagnosed.
For some groups of women, the risk assessment tool may not give a good estimate of risk. For women with a strong family history, who may have an inherited gene mutation, the model underestimates risk (more on genes and breast cancer) [2]. The original model was based on data from white women. Recently, the model was updated to estimate risk for African American women using data from the Contraceptive and Reproductive Experiences (CARE) Study. However, it's still not clear how well the model works in other populations.
With current limitations, it's important to remember that the risk assessment tool can be useful, but it is not a perfect predictor of risk. The model cannot tell whether or not you will get breast cancer. Further, it was designed to be used by health care providers. This makes it hard to understand what the risk it calculates means for you. If you have questions about your risk of breast cancer, speak with your health care provider.
Visit the National Cancer Institute Web site to access the Breast Cancer Risk Assessment Tool.
Looking ahead at risk assessment
As research in the risk assessment field grows, tools like the Breast Cancer Risk Assessment Tool will improve in their ability to predict risk in a broad population of women. For more on new methods of assessing risk, visit Emerging Areas in Estimating Risk.
Updated 11/06/09
