New exam helps detect breast cancer

March 29, 2018 GMT

Starting April 9, Beatrice Community Hospital will offer a new type of mammography that’s aimed at reducing both false positives and false negatives in breast cancer screening.

It’s called digital breast tomosynthesis or 3D mammography, and it has the potential to reduce false positives by nearly half and can identify breast cancers that might have been missed by traditional mammogram somewhere between 10 and 60 percent more often.

The brand name of the new machine is the Genius 3D Mammography exam and, while it operates in a similar fashion to standard two-dimensional mammograms, it takes dozens of images as opposed to the one or two images of the standard exam.

Jesse Young, the director of diagnostic imaging at BCH said that if you think of the breast as a loaf of bread, and you’re trying to find two or three small nuts—or tumors in this case, just taking a photo of it wouldn’t really be that useful in finding the hidden nuts.

What the 3D exam does is comparable to a CAT scan, taking layered x-ray images of breast tissue, kind of like slicing bread.

“What if you took that loaf of bread and now cut it up into 50 small slices, pulled each little slice out and then looked at it,” Young said. “Your odds now of seeing that nut within one of those little tiny slices is much greater.”

Dr. Kim Coleman compared it to a photo of a snake. The snake on top of a plain background is very easy to see, but when that snake is on top of leaves that match its color, it’s nearly invisible.

The denser the breast tissue is, the harder it is to spot the cancer with a traditional mammogram. With digital breast tomosynthesis, each of those x-ray images give a clearer picture of what’s inside that tissue.

Women whose mammograms reveal that their breast tissue is dense receive a letter in the mail that lets them know that, while normal, their denser breast tissue could be an issue, Coleman said.

“It makes it more difficult to detect the cancer, and the dense tissue itself puts you at slightly increased risk,” she said. “We’re not sure how much, but the actual dense tissue itself has more risk of becoming cancer.”

Having dense breast tissue isn’t necessarily a good or bad thing, it’s just nature, Coleman said. While it can vary a little bit with hormones and age, like having blonde hair or blue eyes, it’s just the way you are, she said.

“With dense breasts, this new machine really shines, as far as being able to detect cancer,” Young said.

The 3D mammography exam is covered by Medicare and by about 90 percent of insurance companies, he said. It runs about $100 more than a standard mammogram and requires a referral from a doctor.

There’s some argument over what the best age and frequency to get a mammogram is. Coleman encouraged women to talk with their doctors for a recommendation on when to have it done.

While the machine can help to detect breast cancer earlier, which increases survival rates, it also reduces quite a few false positives.

The hospital has about a 10 percent callback rate following standard mammograms, Young said. Of the 1,500 mammograms they do, 40 required a biopsy and, of those biopsied, four out of five turned out not to be cancer.

Using the digital breast tomosynthesis exam, false positives have been cut by about 50 percent, Coleman said.

The exam is giving doctors a new way of looking inside breasts and giving patients a better survival rate, Young said.

“It’s simply about finding things that were hidden before,” he said.