What is the recommended breast cancer screening interval for average-risk women?

• A. Biennial mammography for women 50-74, with individualized decision-making for 40-49
• B. Annual mammography for women 50-74
• C. Biennial mammography for women 40-74
• D. One-time mammography at age 50

Answer: (A)

The key point is how often average‑risk women should be screened with mammography and at what ages benefits outweigh harms. For average‑risk individuals, the USPSTF recommends screening every two years for women aged 50 to 74. In the 40s, the decision to start screening should be personalized after discussing potential benefits and harms, since younger women have a higher chance of false positives and overdiagnosis, with a smaller absolute reduction in mortality. The interval of every two years in the 50–74 group balances catching cancers early with minimizing unnecessary tests and procedures.

Annual screening, while it may detect some cancers sooner, increases harms like false positives, biopsies, anxiety, and radiation exposure without a proportional improvement in mortality for this average‑risk population. Starting screening only once at age 50 would miss cancers that develop earlier or later and isn’t aligned with ongoing surveillance. And starting at 40 for everyone would expose many younger women to harms without clear benefit, given their lower baseline risk.

So, the recommended approach is to screen biennially from 50 to 74, with individualized discussion for starting screening in the 40s. This reflects the balance USPSTF aims for between the potential lives saved and the potential harms of screening.