Screening Fails to Affect Breast Cancer Mortality
U.K. study sees no benefit in 40-year program (June 11)
New research analyzing breast cancer mortality data spanning almost 40 years concludes that breast cancer screening does not show an effect on mortality statistics. The research, published in the Journal of the Royal Society of Medicine, looked at mortality trends before and after the introduction of the U.K.’s National Health Service Breast Screening Program in 1988.
Researchers at the University of Oxford sought evidence of a decline in population-based breast cancer mortality that could be attributed to the implementation of mammographic screening programs. They concluded that population-based mortality statistics for England do not show a past benefit of breast cancer screening.
The new research contrasts with the findings of an independent review commissioned by the Department of Health, published in 2012, which concluded that there was a 20% relative reduction in mortality from breast cancer in women invited to screening. The review also found that for each breast cancer death prevented, about three over-diagnosed cases will be identified and treated.
Lead researcher Ms. Toqir Mukhtar says that while the new results do not rule out a benefit of breast cancer screening at the level of individual women, “the effects are not large enough to be detected at the population level.”
“Measuring the effectiveness of mammography screening is a fundamental area of concern in countries which have established mammography screening program,” she says. “Clinical trials have indicated that several years have to elapse between the start of screening and the emergence of a reduction in mortality. Yet our data show that there is no evidence of an effect of mammographic screening on breast cancer mortality at the population level over an observation period of almost 40 years.”