Cooley Dickinson Hospital in Northampton embraces 3-D mammography said to find deeper cancers

Last modified: Monday, October 05, 2015
Deborah Grandmont, the women’s imaging supervisor at Cooley Dickinson Hospital in Northampton, says there’s a standard expression: “Nothing’s real in radiology unless you see it in two images.”

But for the past two years at Cooley Dickinson, 3-D mammography, or breast tomosynthesis as it is also called, has provided a look at multiple layers of breast for a more in-depth search for tumors.

Traditional mammography, the kind that currently happens at every other imaging unit in the Valley, is a 2-D affair. The machine takes a picture from one vantage point, then another. But in a 3-D machine, that tube moves in a circular fashion, taking many images from many angles to provide a more complete picture.

Grandmont says that from her viewpoint, 3-D mammography is a dramatic step forward, enabling the detection of significantly more tumors at Cooley Dickinson. “In the first year, we found something like eight breast cancers that we didn’t see at all with the 2-D technology,” she said. “There’s really a world of difference. You can see so much more sharply. With this machine, you can see a 1 millimeter slice at a time.”

According to a 2014 study published in the Journal of the American Medical Association involving 454,850 scans, 3-D mammography cancer detection rates were 5.4 per 1,000 patients versus 4.2 per 1,000 with standard mammography. The rate of callback for suspicious results was 15 percent lower with 3-D.

Though the technology is increasingly available, many medical centers have been slower to embrace it.

Dr. Richard Hicks, Chairman of Radiology at Baystate Health based in Springfield, says in his view the jury is still out on how much of a difference it makes. Given the prospect of rolling out an expensive new technology over its five hospitals and other imaging facilities, he says, Baystate is taking a “measured,” approach.

“Large trials reporting positive results are just beginning to be published, with no data yet that digital breast tomosynthesis actually affects outcomes,” he said in a prepared statement. Still, he added, the medical center is “formulating plans” to add 3-D mammography technology to its offerings.

Cooley Dickinson spokesperson Christina Trinchero declined to disclose how much the hospital, which is affiliated with Mass General Hospital in Boston, invested in its machine.

How it works

To demonstrate 3-D, Grandmont stood at a console that, with its clear shielding, curvy construction, and glowing screens, looks like it came from a Star Trek set. Two X-ray images popped up side by side — one produced by a 2-D process, the other 3-D.

The image produced by the newer technology looks at first glance less clear than the standard image.

That’s because, Grandmont explained, it initially appears just as flat as a 2-D version since it’s on a flat screen. But it is really many 2-D images stacked up.

Imagine how a large number of colored layers of sediment combine to form the solid walls of the Grand Canyon — tomosynthesis creates an image of the breast in a similar (if more complicated) layer-by-layer way, stacking the slices together to make a three-dimensional on-screen object.

The real advantage becomes evident if you imagine, too, that each layer can also be examined on its own. When Grandmont pulls the control back and forth, those 1 millimeter slices become visible in sharp detail, one at a time in quick succession. It’s the difference between a standard computer image and an animated one.

That layer-at-a-time ability is useful in mammography because of the nature of breast tissue.

“Young women and premenopausal women have more fibroglandular tissue, and as we age it breaks down to fat,” Grandmont said.

Fibroglandular tissue is the denser, non-fat tissue of breasts, which contains milk glands, milk ducts and connective tissue. Grandmont explains that the more fibroglandular tissue there is in a breast, the harder it is to see tumors via X-ray. That’s because it can often fold up on itself, something called a “summation artifact.” When that happens, tumors can get hidden in the mammogram image.

The 3-D mammogram gets around that problem, by literally getting around the breast from many angles.

“Everybody can interpret mammograms better with this technology,” Grandmont said. “It’s a tool that helps the radiologist read with more certainty.”

The better technology, particularly if it’s part of annual screening, she said, reveals lower-grade cancers.

“Patients can go in and have surgery and be cured. There are still women who don’t believe in an annual mammogram, but I’ve seen women who skipped a year and, unfortunately, it makes a difference in the path they’re going to have to walk.”

Even if a cancer is advanced, Grandmont says, the new technology can help by providing a more accurate view of the unhealthy tissue and any satellite lesions, or smaller secondary tumors.

Grandmont has been women’s imaging supervisor at Cooley-Dickinson since 2008, but, she says, she has done mammography for over 30 years. In that time, the chief innovation she’s seen is digital processing of images, in which aspects like contrast can be manipulated revealing a more detailed picture.

Her long perspective provides another intriguing bit of information about 3-D tech: it’s actually been around since the 1970s. It’s the ability to apply it to breasts that arrived more recently. That arrival brings more improvements yet. “Many patients say it’s not as uncomfortable,” said Grandmont, as not as much force is needed to compress the breast to get a good picture.

In her view, the advances brought by 3-D mammograms point to what will happen in coming years: “I believe it will be the new standard of care.”

James Heflin can be reached at jheflin@gazettenet.com.