A study of 16 million women aged 40 and older who were followed for 10 years suggests that more breast cancer screenings led to a greater incidence of cancer diagnoses. However, increased screening did not result in decreased breast cancer-associated mortality. The incidence of small breast cancer diagnoses increased as screening increased, but the incidence of larger breast cancers did not decrease with increased screening. The authors suggest that there may be widespread overdiagnosis of breast cancer.

Source: JAMA Internal Medicine, September 2015.