What is the Gail Model / Breast Cancer Risk Assessment Tool?
The Gail Model (officially the Breast Cancer Risk Assessment Tool, or BCRAT) was developed by scientists at the National Cancer Institute and NSABP. It uses a woman's personal medical history, reproductive history, and family history of breast cancer to estimate the probability of developing invasive breast cancer over the next 5 years and over her lifetime (up to age 90). See also our Clomid Ovulation Calculator.
Who is this tool validated for?
The tool has been validated primarily for women in the United States who identify as White, Black/African American, Hispanic, or Asian/Pacific Islander. It may underestimate risk in Black/African American women with previous biopsies and Hispanic women born outside the United States. It is not designed for women who have already been diagnosed with breast cancer, DCIS, or LCIS.
What does '5-year risk' mean?
Your 5-year risk is the estimated probability that you will develop invasive breast cancer in the next five years. For example, a 5-year risk of 2% means approximately 2 out of every 100 women with your profile would be expected to develop breast cancer over that period.
What is considered a high risk result?
A 5-year risk of 1.7% or greater is generally considered 'high risk' and is the threshold often used to discuss preventive interventions such as chemoprevention medications. A lifetime risk above 20% may also qualify a woman for enhanced screening, such as annual MRI in addition to mammography.
Should women with BRCA mutations use this tool?
No. The Gail Model is not appropriate for women with known BRCA1 or BRCA2 mutations or other hereditary syndromes associated with high breast cancer risk. Other specialized tools (such as BOADICEA or Tyrer-Cuzick) are better suited for these individuals.
What does atypical hyperplasia mean and how does it affect risk?
Atypical hyperplasia refers to abnormal but non-cancerous cells found in a breast biopsy. Having atypical hyperplasia significantly increases breast cancer risk—roughly 4 to 5 times compared to women without it—and is one of the stronger risk factors captured by the Gail Model.
How accurate is this risk estimate?
The Gail Model provides a statistical estimate based on population data. While it is well-validated for groups of women, it cannot precisely predict which individual woman will or will not develop breast cancer. Some women with low estimated risk do develop breast cancer, and many with high estimated risk do not. These results should be discussed with a healthcare provider.
Can this tool be used by men?
No. The Gail Model was developed and validated exclusively for women. Although men can develop breast cancer, the risk factors and statistical models differ, and no equivalent widely-validated online tool currently exists for male breast cancer risk estimation. You might also find our calculate Birth Control Cost useful.