Breast Cancer Screening with 3-D Technology Finds More CancersJun 25, 2014
Researchers from several radiology centers across the US have found that 3-D mammograms have some advantages over standard digital mammograms, the kind most women receive for regular breast cancer screening. (Screening is testing for cancer in people with no symptoms of the disease.) In a study of 454,850 breast scans, 3-D mammograms found slightly more cancers than standard digital mammograms and caused fewer women to be called back for more testing for what turned out not to be cancer.
3-D mammography is another way to refer to digital mammography with tomosynthesis, in which a machine takes many low-dose x-rays as it moves over the breast. The images taken can be combined into a 3-dimensional picture, which may allow doctors to see inside the breast more clearly than with a standard 2-view mammogram, and possibly find more cancers. These 3-D mammograms expose the breasts to more radiation than standard mammograms, but remain within FDA-approved safe levels for radiation from mammograms.
In the study, published June 24, 2014 in Journal of the American Medical Association, researchers looked at data from 13 medical centers before and after they began using tomosynthesis. They found that digital mammograms with tomosynthesis detected 1 additional cancer for every 1,000 scans and resulted in 15% fewer false alarms – women called back for more tests and then found not to have cancer. The study was not designed to find out whether mammograms using tomosynthesis can save more lives than standard digital mammograms.
The American Cancer Society recommends women age 40 and over get a screening mammogram every year, along with a breast exam by a doctor or nurse. Machines equipped with tomosynthesis technology are currently available in only about 1,000 medical facilities in the US, and women may have to pay more to get the newer test.
Robert Smith, PhD, American Cancer Society senior director of cancer screening, says the study does not mean all women should seek out 3-D mammograms. Smith said although the study showed an important improvement in cancer detection rates, the improvement was small. The more dramatic finding, he said, was having less chance of being called back for additional testing.
Smith said, “Women who may be concerned that this technology is not available in their community should not for 1 second think they’re getting substandard mammograms.”
Smith said women who are concerned about their individual risk for breast cancer and whether they would benefit from digital mammography with tomosynthesis should talk to their doctor.
The American Cancer Society is participating in conversations with the National Institutes of Health and other organizations about how to further study the benefits and risks of tomosynthesis for breast cancer testing.
Breast Cancer Screening Using Tomosynthesis in Combination With Digital Mammography. Published June 24, 2014 in Journal of the American Medical Association. First author Sarah M. Friedewald, MD, Advocate Lutheran General Hospital, Park Ridge, Ill.