Study Finds Mammograms Are Not Reducing Mortality Rates
Yearly mammograms will not reduce the rate of breast cancer mortality, a new study states. Published Tuesday in the British Medical Journal, it reports the findings of a study that began tracking two groups, a total of 89,835 women, in 1980. For one group, mammograms and physical examinations occurred on an annual basis. In the control group, there was no annual mammography, but physical examinations did take place, and the participants remained under the care of their family doctor. Both groups were then followed for a period of 25 years.
The purpose of the study was to assess the effectiveness of mammography in reducing breast cancer mortality. Regular mammogram screening takes place with this goal in mind, and to assess whether or not it is a worthwhile process, the researchers state it “must be evaluated in randomised screening trials, with breast cancer mortality as the endpoint.”
For five years (between 1980 and 1985) screening took place. During that time, 666 invasive cancers were diagnosed in the mammography group, and 524 in the control sector. In the former, 180 women died, and 171 died from the latter. After studying the findings the researchers found that, “Annual mammography does not result in a reduction in breast cancer specific mortality for women aged 40-59 beyond that of physical examination alone or usual care in the community.”
Furthermore, regular mammograms could be leading to “over-diagnosis.” When the researchers evaluated the cases that were detected, 106 of invasive cancers (or, 22 percent) were determined to be over-diagnosed. For every 424 women who received mammography screening in the trial, one was over-diagnosed. This means that what was found would not necessarily have become become clinically apparent during the woman’s life.