"the downward trends in breast cancer mortality in Sweden have evolved practically as if screening had never existed”

http://www.ncbi.nlm.nih.gov/pubmed/22811437

J Natl Cancer Inst. 2012 Jul 17. [Epub ahead of print]

Mammography Screening Shows Limited Effect on Breast Cancer Mortality in Sweden.

[No authors listed]

The researchers expected that screening would be associated with a gradual reduction in mortality, especially because Swedish mammography trials and observational studies have suggested that mammography leads to a reduction in breast cancer mortality. In this study, however, they found that breast cancer mortality rates in Swedish women started to decrease in 1972, before the introduction of mammography, and have continued to decline at a rate similar to that in the prescreening period. “It seems paradoxical that the downward trends in breast cancer mortality in Sweden have evolved practically as if screening had never existed,” they write. “Swedish breast cancer mortality statistics are consistent with studies that show limited or no impact of screening on mortality from breast cancer.”