Annual Mammograms May Have More False-Positives
Screening Mammograms Every Two Years Cut the Chances of False Alarm, Study Shows
Digital vs. Film Mammography
In a related study, researchers found that digital and film mammography were similarly effective in picking up cancers in most women.
Digital and film mammography both use X-ray. But in film mammography, the image is created directly on a film, while digital mammography takes an electronic image that is stored in a computer. Unlike with film mammography, radiologists can use software to manipulate digital mammograms so they may be easier to interpret.
The FDA approved the first digital mammography system nearly 12 years ago, before any large studies had compared it to film mammography, says Karla Kerlikowske, MD, author of the second paper.
By the time the first such study began enrolling women a decade ago, "the horse had left the barn," says Kerlikowske, a professor of medicine at the University of California, San Francisco. Today, she says, more than two-thirds of accredited mammography machines in the U.S. are digital, which is more expensive than film.
Kerlikowske and co-researchers analyzed real-world data from about 330,000 women aged 40 to 79 who underwent nearly 900,000 mammograms at facilities in the Breast Cancer Surveillance Consortium. A little more than a third of the mammograms were digital.
Kerlikowske says her study found that the two technologies are similar in women 50 to 79. If digital had been worse, she says, "then we'd be in trouble."
Because radiologists can manipulate digital mammograms, women who opt to begin screening in their 40s might choose digital mammography to optimize cancer detection in their denser breasts, the researchers write.
The new studies appear in the Annals of Internal Medicine.