The results were encouraging: the DMT detected six of seven biopsied cancers, as well as one cancer missed by an earlier clinical exam. Even better, it was extremely specific. Every lesion it identified as benign was actually benign.

"We got better results than we expected, but I have no doubt in my mind that when we do a bigger study, those numbers are going to change," Williams tells DOTmed News.

Still, it's a promising start. The positive predictive value - or the fraction of positive findings that turn out to be true - was 100 percent in the study, a figure Williams naturally expects to be reduced during a larger clinical trial that enrolls more people. But even if it ends up at 80 or 70 percent, it would still be a huge improvement, he says. That's because in traditional mammography, the positive predictive value is about 25 percent, meaning that three out of four biopsies triggered by positive mammo findings are negative, says Williams.

The findings also compare favorably with breast MRI, generally held to be one of the most sensitive modalities. An International Breast MR Consortium study, published in the Journal of the American Medical Society, found an MRI sensitivity of 88 percent and a specificity of 68 percent. In Williams' pilot study, the DMT's sensitivity and specificity were 86 percent and 100 percent, respectively.

Road to adoption

Nonetheless, don't expect DMT scanners to replace mammography as a screening tool overnight.

While the hybrid scanner has the potential to improve detection of cancer and diagnosis, it also creates much more information than 2D mammography, and requires more time to review. At first, this could slow down a radiologist's workflow as they have to flip through many slices.

"I think there's definitely going to be a learning curve associated with going from digital mammography to digital tomosynthesis," says Williams. "But radiologists who read MRI and read CT have a much larger volume of data to handle, and they do it well, so I have no doubt that radiologists will be able to adjust to tomosynthesis, and will do it well."

Another challenge will be the transition. Radiologists check for breast cancer by comparing a current mammogram of a breast with an older one, to look for differences. That could be tricky if the older one is two-dimensional, and the new one is in 3D.

This transition resembles the one faced by radiologists making the switch from analog to digital mammography, observes Williams. To make it work, some simply compare the older film images on a light box with the newer digital ones on a monitor in the reading room. Others actually print out the digital images on laser film and hang them side by side with the older analog images on the light box.

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