What Is the Value of Mammograms for Women in Their 40s?

Among younger women (age range, 40–49), breast cancer is uncommon, and screening mammograms are associated with high false-positive rates and unnecessary biopsies; accordingly, the U.S. Preventive Services Task Force (USPSTF) has recommended against routinely screening women before age 50 (JW Womens Health Nov 16 2009). In Sweden, screening mammography was initiated for women (age range, 40–74) in 1986. National guidelines soon were modified so that financially challenged counties could curtail screening for women who were younger than 50; thus, about half of Swedish counties discontinued screening women in their 40s. Researchers assessed breast cancer mortality in screened versus unscreened women.

From 1986 to 2005, 803 screened women and 1…