The controversy surrounding routine mammograms revolves around the frequency of false-positives and unnecessary biopsies associated with the technology. New research shows that 3-D mammographic technology may be able to clear the confusion.
This new screening method, coupled with ordinary mammograms, leads to 15% fewer unnecessary callbacks but more accurate detection of the tiniest tumors, often missed by mammograms alone.
The largest study of 3D mammography ever conducted resulted in these findings, published in the Journal of the American Medical Association (JAMA) on Tuesday, June 25.
The study used three-dimensional mammograms, also called tomosynthesis, made by Hologic Inc., paired them with traditional mammograms, and compared the results to single 2D mammogram testing. The combination of the two screenings detected 41% more cancers in addition to the fewer callbacks. Unlike conventional mammograms, tomosynthesis allows doctors to locate tumors deep within tissue layers. The researchers determined these results by analyzing data from 13 breast centers, both academic and nonacademic, adding up to a total of 454,850 mammograms.
The American Cancer Society recommends women receive annual mammograms beginning at age 40. Due to the amount of false-positives that sometimes result from traditional mammograms, in 2009 the U.S. Preventative Services Task Force recommended against annual mammograms for women at low risks of developing breast cancer.
According to the researchers in the JAMA study, "intervention is more likely to result in long-term survival. Despite this benefit, mammography has drawn criticism for excessive false-positive results, limited sensitivity, and the potential of overdiagnosis of clinically insignificant lesions."
Often false-positives lead women to obtain biopsies in which tissue lesions turn out to be fine. While the tomosynthesis study showed a reduction in recall rates, the researchers did not calculate a decrease in the rate of biopsies. In order to achieve such a reduction, technology would have to be improved so as to non-invasively distinguish between benign and malignant tumors. There are some methods currently under study, but with such procedures, it is important to gather as much data as possible before releasing them.
Hologic Inc. has the only approved tomosynthesis devices in the U.S. There are over 1,100 such devices in use, but many insurance companies are not yet offering reimbursement for the technology.
