A U.S. Preventive Services Task Force-commissioned analysis found that biennial mammography screening starting at age 40 offers the optimal balance between preventing breast cancer deaths and minimizing screening harms. Screening every other year from ages 40-74 prevented approximately eight breast cancer deaths per 1,000 women and added 165 life-years, with about 1,376 false-positive findings and 14 overdiagnosed cases per 1,000 patients. Compared to starting screening at age 50, beginning at 40 prevented up to 19% more deaths with only modest increases in harms. While annual screening prevented two additional deaths per 1,000 women, it significantly increased harms including 15,000 more mammograms, 700 more false-positive recalls, 87 more benign biopsies, and seven more overdiagnosed cases per 1,000 women.

Source: Annals of Internal Medicine