Risk assessment for breast cancer

Genetic testing for individuals with familial or hereditary risk for breast cancer is essential to improving prevention and survival. Identifying unaffected BRCA1/2 mutation carriers before they develop breast cancer can reduce their risk and increase survival through increased intensity and frequency of screening, prophylactic surgery, and use of chemopreventive agents. Although the tools for genetic testing have been available for the past 20 years, nearly 95% of unaffected BRCA carriers remain unaware of their risk. The barriers to genetic screening are multiple. To identify patients for genetic testing, the clinician must first take the family history; analyze it using hereditary risk models, guidelines, or intuition; refer the patient for genetic testing; and most important, ensure that the patient follows through. With each of these steps, a certain proportion of patients is lost. Mary-Claire King, the human geneticist who discovered the BRCA mutation, once stated that "to identify a woman as a carrier only after she develops cancer is a failure of cancer prevention." We can do better.