Over the past 15 years, there has been active discussion in the medical community about whether the benefits of mammography outweigh the risks. This debate was sparked again when two Danish scientists reviewed the evidence on mammography. They felt that most of the randomized controlled trials were too flawed to give good information about mammography. They did not include these trials in their analyses. Using only the data from the remaining studies, they concluded that mammograms did not change a woman's chance of dying from breast cancer [37-38].
Most major health organizations disagree with these conclusions, and feel that mammography does save lives. When researchers went back and looked at the results in response to the Danish report, they agreed that there were some problems with certain studies. However, they also felt that the studies still showed that mammography was a valuable screening tool.
There are valid concerns about over-diagnosis and over-treatment. Since the introduction of mammography, the number of women diagnosed with ductal carcinoma in situ (DCIS) has increased. Although some DCIS goes on to become invasive cancer, many may not. At this time, there is no way to tell which cases of DCIS will go on to invasive cancer and which will not. Therefore, women with DCIS are treated with a lumpectomy (also called breast conserving surgery) plus radiation therapy or mastectomy, even though some cases may never become invasive. This means that some women with DCIS may be "over-treated” because their DCIS would not have become invasive cancer. However, at this time, the standard of care is to treat each case of DCIS.
What does this mean for you? While any health decision is a personal one that involves weighing risks and benefits, most health organizations recommend that women get regular mammograms starting at age 40. Despite some ongoing debate, mammography is still the best screening tool widely used today for the early detection of breast cancer.
Read more from our Chief Scientific Advisor, Dr. Eric Winer, as he comments on the issue of mammography leading to over-diagnosis and over-treatment.
Updated 10/16/09
