Women who were a mammogram are less likely to die of breast cancer, but also more chances of being found and treated a cancer that threatens their health, according to a new review of six trials involving ofWomen half a million means that for every 2,000 women who underwent mammography in a live 10 years longer with diagnosis and treatment of breast cancer, but 10 will receive unnecessary treatment, the doctors explained Peter C. Gotzsche and M. Nielsen, Nordic Cochrane Centre in Copenhagen.
"It is unclear whether the control studies help more than harm For women who were recommended such controls, they should report the risks and benefits," he wrote.
The use of mammography as a control study was extensively studied, but its benefits and potential dangers remain controversial, the authors note.
To investigate further, the researchers analyzed the results of six major studies conducted in the U.S. and Europe, that compared the use and non-use of mammography in healthy women 40, 50 and 60, with no family history breast cancer.
The analysis included 500,000 women who underwent the study or control.
After seven years, the women that they had mammograms were 20 percent less likely to have died of breast cancer than women in the group of "control", the researchers found.
But Gotzsche and Nielsen suggested that this reduction is closer to 15 percent, given the variation in the quality of the trials analyzed.
However, the risk that a woman was treated for a cancer that threatened his life was 30 percent higher in the group undergoing mammography.
The real differences were small, since the risk of cancer mortality declined by 0.05 percent with regular breast checks, while the danger of overdiagnosis rose 0.5 percent to these controls.
Proponents of the control studies focus on its benefits while saying little or nothing about its risks, say researchers.
"Therefore, most women tend to exaggerate the benefits and not be aware of the main drawbacks of the control studies," wrote the authors.
To increase the effectiveness of these mammograms, more research is needed on how to distinguish between malignant tumors and "the many benign tumors that are identified in the control studies and need no treatment," they said.
SOURCE: The Cochrane Library
