Which residual lifetime risk percentage qualifies as high risk?

• A. ≥5%
• B. ≥10%
• C. ≥15%
• D. ≥20%

Answer: (D)

Understanding how residual lifetime risk is categorized helps you see why twenty percent is the threshold for high risk. In this context, residual lifetime risk is the chance of developing the disease over the rest of a person’s life given they are currently unaffected. For breast cancer, the general population lifetime risk is about 12–13%, so a remaining risk of twenty percent or more marks a substantial elevation that would push a patient into a high-risk category. That level of risk often prompts more intensified surveillance (such as MRI in addition to mammography) and consideration of genetic counseling or testing, reflecting a meaningful increase above average risk. Lower thresholds—five, ten, or fifteen percent—represent mild to moderate increases but typically do not trigger the same level of high-risk management. Therefore, twenty percent or higher is the cut-off that best fits the designation of high risk.