Mammography Screening and Breast Cancer Mortality: Long-Term Advantages

The 2009 U.S. Preventive Services Task Force guidelines on screening mammography rekindled controversy about routine breast imaging (JW Womens Health Nov 16 2009). In a Swedish trial, >133,000 women without histories of breast cancer were randomized in the late 1970s to usual care or single-view mammography (every 24 months if age 40–49 at entry; every 33 months if age 50–74) for 7 years. Now, researchers have assessed the effects of screening on breast cancer mortality at a maximum 29-year follow-up.

In the screening group (77,080 women), 351 deaths from breast cancer occurred; in the usual-care group (55,985 women), 367 such deaths occurred. Risk for breast cancer death was 31% lower in the screening group (P<0.0001). The number of women n…