A new analysis examines the risks of overdiagnosis of breast
cancer after mammograms. / Becky Shink, AP Up to 70,000 American
women a year are treated unnecessarily for breast cancer because
they were screened with mammograms, according to an analysis in
today's New England Journal of Medicine that's likely to
reignite a running debate over the value of cancer screening.
The study, whose results are already being challenged by other
cancer experts, finds that nearly one in three breast cancer
patients ‚?? or 1.3 million women over the past three decades
‚?? have been treated for tumors that, although detectable with
mammograms, would never have actually threatened their lives.
The study lays bare perhaps the greatest risk of cancer
screening, called "overdiagnosis," long acknowledged by doctors
and even advocates of mammograms, but unknown to most women who
undergo the procedures. Overdiagnosis occurs when technology
detects cancers that, although technically malignant, behave as
if they're benign, says study