Gail Model for Breast Cancer Risk
Why Use
It helps determine which risk-reduction options—medical (chemoprevention with tamoxifen), surgical (prophylactic mastectomy) or lifestyle changes only—are most appropriate for individual patients by weighing risks and benefits of intervention versus likelihood of developing cancer.
When to Use
The Gail Model is one of several risk assessment models that can help determine the absolute 5 year risk and lifetime risk of developing breast cancer. Other models include the Tyrer-Cuzick (also referred to as IBIS, International Breast Cancer Intervention Study) model, the Claus model, BRCAPro, and BOADICEA (Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm).
Pearls / Pitfalls
The Gail Model for Breast Cancer risk estimates the absolute 5 year risk and lifetime risk of developing breast cancer. Family history includes only first degree relatives with breast cancer, which is not enough information to estimate the risk of a patient having BRCA mutation. It also underestimates the cancer risk for patients with extensive family history. The Gail Model is a good predictor of risk for populations but not for individuals. It adjusts risk for race/ethnicity. It may underestimate breast cancer risk in patients with atypical hyperplasia and strong family history. The Gail Model was NOT designed to estimate risk for: Women with a prior diagnosis of breast cancer, lobular carcinoma in situ (LCIS), or ductal carcinoma in situ (DCIS). Women who have received previous radiation therapy to the chest for treatment of Hodgkin lymphoma. Women with gene mutations in BRCA1 or BRCA2, or those who are known to have certain genetic syndromes that increase risk for breast cancer. Women of age <35 or >85.
Critical Actions
Patients with elevated breast cancer risk (>1.7%) should be referred to a breast surgeon to discuss possible risk reduction interventions.
Advice
Patients who have an increased risk of developing breast cancer, defined as calculated 5 year risk >1.7%, are candidates for chemoprevention (such as tamoxifen).
More Information
The Gail Model is one of the oldest risk models—originally published in 1989—and well validated. These parameters were used as criteria for the National Surgical Adjuvant Breast and Bowel Project (NSABP) prevention trials to identify patients with increased risk of breast cancer (5 year risk of >1.7%). Lifetime risk estimates assume a life expectancy of 90 years.