Mammography screening is a controversial issue and the potential benefits are often overrated. A recent study has concluded there are risks of over-diagnosis and this is the crux of the problem. There are many questions which are being asked and there are commercial interests involved.
The study was first published in the April 2 issue of Journal of the American Medical Association and has added one more reason to dissuade persons to go for unnecessary mammography tests. The study has analyzed data from 50 years of research.
The question about the benefits of mammography was first raised in 2009 when the U.S. Preventive Services Task Force (USPSTF) made changes in its guidelines for women to have a mammogram once in two years starting from the age of 40. The guidelines now ask women to have a mammogram once every two years starting from the age of 50. However if any woman wants to have a mammogram in her 40’s , the Task Force suggests the woman to discuss the pro’s and con’s of her decision with her doctor.
The changes in the guidelines came after a growing body of opinion and evidence that women in 40’s derive a very ‘small net benefit’ from the screening.
The study was based on clinical trials which were done since 1960’s that mammograms can save lives but the benefits for women in 40’s are trivial. Screening can cut the risk of death from breast cancer by an average of 15% in women in 40’s. It is this small percentage which is having the scientific community worried of over diagnosis. There could be situations where a woman with a benign tumor which is not life threatening, is pushed into going for unnecessary surgery chemotherapy and radiation.
Experts opine that there are many Breast cancers which are not discernible but could show in a mammogram and are treated.
Keating, of Harvard Medical School and Brigham & Women’s Hospital in Boston says “We have no way of knowing which patients will progress. So we have to treat everyone we diagnose. We think mammography has a benefit, but it’s smaller than many people believe. And the risk of over diagnosis, in particular, has not received a lot of attention.”