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Thursday, November 22, 2012

Health Care Reform Articles - November 22, 2012


Cancer Survivor or Victim of Overdiagnosis?



Hanover, N.H.
FOR decades women have been told that one of the most important things they can do to protect their health is to have regular mammograms. But over the past few years, it’s become increasingly clear that these screenings are not all they’re cracked up to be. The latest piece of evidence appears in a study in Wednesday’s New England Journal of Medicine, conducted by the oncologist Archie Bleyer and me.
The study looks at the big picture, the effect of three decades of mammography screening in the United States. After correcting for underlying trends and the use of hormone replacement therapy, we found that the introduction of screening has been associated with about 1.5 million additional women receiving a diagnosis of early stage breast cancer.
That would be a good thing if it meant that 1.5 million fewer women had gotten a diagnosis of late-stage breast cancer. Then we could say that screening had advanced the time of diagnosis and provided the opportunity of reduced mortality for 1.5 million women.
But instead, we found that there were only around 0.1 million fewer women with a diagnosis of late-stage breast cancer. This discrepancy means there was a lot of overdiagnosis: more than a million women who were told they had early stage cancer — most of whom underwent surgery, chemotherapy or radiation — for a “cancer” that was never going to make them sick. Although it’s impossible to know which women these are, that’s some pretty serious harm.
But even more damaging is what these data suggest about the benefit of screening. If it does not advance the time of diagnosis of late-stage cancer, it won’t reduce mortality. In fact, we found no change in the number of women with life-threatening metastatic breast cancer.
The harm of overdiagnosis shouldn’t come as a surprise. Six years ago, a long-term follow-up of a randomized trial showed that about one-quarter of cancers detected by screening were overdiagnosed. And this study reflected mammograms as used in the 1980s. Newer digital mammograms detect a lot more abnormalities, and the estimates of overdiagnosis have risen commensurately: now somewhere between a third and half of screen-detected cancers.


Study links mammograms to overtreatment

Breast cancer specialists reject findings, back testing

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