At RSNA 2011, Dr. Stephen Rose, founder and president of Houston Breast Imaging was invited to give a presentation on digital breast tomosynthesis. At the time, although the technology had received a fair share of write-ups, radiologists with handson experience were rare since earlier that year, Hologic’s Selenia Dimensions was the first breast tomosynthesis system to receive FDA 510(k) clearance.

DOTmed News interviewed Rose during the show and while he praised the technology, he admitted there were some challenges to overcome. For one, digital breast tomosynthesis, or 3-D mammography, existed for years and was in use in research facilities, but it was a new technology for the general health care marketplace. But digital 2-D mammography was also still relatively new to market, which meant facilities that hadn’t recouped the investment yet might be reluctant or financially unable to take a leap again so soon. That was coupled with a complete absence of reimbursement dollars, meaning facilities enlisting the aid of 3-D mammo would have to consider the peripheral value of the technology.

Rose predicted reimbursement would land within 20 percent of the current digital 2-D mammogram reimbursement scale. He also predicted that it would completely replace that technology by 2016. Although studies supporting the promise of 3-D are being introduced fairly regularly, Rose’s predictions have yet to be realized.

3-D mammo finds a home
Hospital consolidation may be a boon to 3-D mammo. Although it has led to less competition for the remaining facilities, they still need to attract and retain a customer base and the large health care systems are more likely to have the capital to do it. “Digital breast tomosynthesis is still evolving in many ways, it’s certainly very expensive,” Rohit Inamdar, senior associate and medical physicist for the Applied Solutions Group at ECRI Institute tells DOTmed HealthCare Business News. “It’s the well-capitalized and well-resourced that will be the early adopters. The counterpoint, if you are a large, independent women’s imaging center, having DBT in your facility may give you a strong marketing tool,” he says.

With 3-D mammo not receiving reimbursement, marketing is likely to be somewhere on the list of benefits when facilities are considering the purchase. That was certainly a point that Dr. Lara Hardesty, the director of breast imaging for the University of Colorado drove home when she made the case to purchase a 3-D mammo unit. “As a university practice, we have a very large number of patients who, once they’re diagnosed with an abnormality, want to come to us for care,” she tells HCBN. “But we had a difficult time getting them in for an initial screening.”



Hardesty was able to get approval by pointing out the marketing foothold 3-D would deliver. “If we could be the only ones in town with the technology, we could convince patients to come to us for screening,” she says. “And we were the only ones in town with it for about a year.” That may be part of the reason why there are currently more about 1,100 3-D units installed in the U.S. — a modest number compared to 2-D digital’s 8,000 but impressive when one considers how new the technology is, how much more it costs and that there’s currently only one company providing those units.

“In the U.S. we have commercial systems in all 50 states,” Jim Culley, senior director of corporate communications at Hologic tells HCBN. “Over four million women in the U.S. will be imaged using the 3-D mammography system by our estimates.”

With Hologic being the only company currently in the U.S. market, there haven’t been the price wars seen for other modalities or technologies. “Since there’s only one on the market, you’ll probably pay $150k more for that unit than a 2-D digital mammography unit,” says ECRI’s Inamdar.

Past and present
Digital breast tomosynthesis has existed at least in theory for more than two decades. In application, it has existed for about half that time, largely due to Dr. Daniel Kopans. Kopans, a professor of radiology at Harvard Medical School, was an early advocate for breast tomosynthesis. He is also widely recognized as the father of breast tomosynthesis, holding a number of key patents regarding the technology.

Kopans realized DBT had potential much earlier than the majority of the health care sector. “I recognized the importance of being able to remove the normal breast tissue from the mammograms to see the individual planes,” he said in an email to HCBN. But the technology needed work. “All of the tomographic techniques at that time required far too much radiation, but I read about the general principles of tomosynthesis and realized its potential for breast evaluation, but I had to wait until the early 1990s because I needed digital images and computers to develop the technique,” he said.

In 1992, Kopans shared some articles on tomosynthesis with physicist colleagues and the group became part of the National Digital Mammography Development Group (NDMDG). The group helped GE and Fisher Imaging develop their prototype digital mammography systems and this led to further collaboration with GE which gave the NDMDG access to a prototype digital breast tomosynthesis detector prototype.

GE was slow to move forward with the technology in the U.S., which gave Hologic
a big opportunity. Although Hologic is currently the only domestic player, GE and Siemens have systems on the market in Europe and will likely hit the American market once they clear regulatory hurdles. Still, Hologic is not waiting for challengers before it reacts. The company released C-View software in early last year, which takes the
3-D image and reconstructs it to 2-D.

The 2-D reconstruction is important because regulatory requirements specify that both a 3-D and 2-D image have to be obtained when utilizing digital breast tomosynthesis The two scans translated to additional dose, but the reconstructive technique requires only the 3-D scan.



Cutting down on false negatives and false positives
In order to better understand why 3-D mammo is getting so much support, it’s necessary to understand the technology. Harvard’s Kopans offered a simple explanation. “Conventional 2-Dimensional mammography is like a book with clear pages. You can hold the book up to the light and see all the words, but they are superimposed and hard to read,” he said. “Normal breast tissue superimposes on cancers and can hide them. Superimposed normal breast tissue can also fool the radiologist into thinking that there is a cancer when there is none. DBT allows the radiologist to see each individual page free from what is in front and what is behind. This allows us to find more cancers, and to reduce the recall rate from screening.”

“Diagnostic accuracy seems to be increasing based on the information we’re seeing from early trials,” says ECRI’s Inamdar.

At the University of Colorado, where they went from one to all four of their units being 3-D, Hardesty shares similar views about the false negatives and positives. The technology pulls off a rare feat — while most technology updates either reduce false negatives or false positives, DBT goes a step further. “The main improvement for us is the ability to see false positives and increase actual detection,” Hardesty says.

Challenges still ahead
In addition to the heftier price tag, 3-D delivers some challenges for staff. “There’s definitely a learning curve,” says Hardesty. “However, my learning curve was less with tomo than it was with digital. We’re very comfortable with the appearance of mammo at this point. The larger issue is that we’re not looking at two images, we’re looking at hundreds. This means the reading time is on average about one and a half times longer,” she says.

Those additional images translate to a need for additional storage.

“Each of these exams is four-and-a-half gigabytes,” says Inamdar. “If you do 20 patients a day, in 10 days you have one terabyte of data to store. Cost can rise rapidly for a large mammography practice,” he says.

But hospitals and imaging centers may soon have a little more money to help pay for that storage. “The American Medical Association panel; accepted the application for CPT codes for tomo in May — three category one codes for diagnosis and treatment for tomo,” says Hologic’s Culley. “The coding will be published in November and the CPT codes and rates will be published in January of 2015.”