New breast imaging devices challenge status quo

Despite an abundance of alternative technologies, x-ray mammography is secure as the preferred means for breast evaluation. At least some of these alternatives, however, will eventually enter the mainstream of medical practice in some capacity.

"As mammography technology is growing, so are adjunctive breast technologies," said John Brenna, executive vice president of CTI. "Mammography is the gold standard, but there are many reasons why new technologies can and should supplement a standard mammogram. If the FDA finds that a device is safe and effective, then we don't see why they wouldn't want to approve it, especially given the critical need to detect breast cancer early."

A top candidate is thermal imaging, which creates a map of hot spots in the breast. Computerized Thermal Imaging (CTI) argues that the infrared camera built into its Breast Imaging System can highlight suspicious tissue. The company has been steadily submitting data to the FDA in hopes of winning a premarket approval.

Another good possibility is optical imaging, which uses light to visualize breast tissue. Imaging Diagnostic Systems (IDS) is grooming its CT laser mammography system as the way to create cross-sectional images of the breast. Dynamic optical breast imaging from DOBI Medical Systems uses red light to detect the abnormal growth of blood vessels.

Driving the development of these and other adjunctive devices is the prospect of detecting or confirming breast cancer using less invasive, less costly, and more efficient means than breast biopsy. Companies reaching this goal will benefit from the cost savings they would achieve by reducing the number of biopsies necessary.

"If you can save 10% to 20% of women with benign disease from having a biopsy, you know the product is valuable," said Dr. Yuri Parisky, director of breast imaging services for the University of Southern California/Kenneth Norris Jr. Comprehensive Cancer Center. "If it makes you a better radiologist 10% to 20% of the time, I think that's good. It doesn't have to be perfect."

Reaching even a level of acceptable imperfection, however, is tough. CTI, DOBI, and IDS are examples of companies whose very survival has conferred on them some credibility. Their credibility will grow with each appearance on the exhibit floor of the RSNA show. The reason is simple: start-ups making such reappearances are the exceptions.

"I would imagine that half the companies that were new at the RSNA won't be around in two years," said Parisky, who was an investigator in the three-year, multicenter trial that evaluated the CTI technology. "They run out of steam, they run out of capital, or they run out of credible science."

Established modalities have had an easier time breaking into breast imaging than innovative technologies. Diagnostic ultrasound is the clearest example. Black-and-white scanners are routinely used to distinguish solid from cystic lesions. The FDA has even approved one form of ultrasound as a means of distinguishing between benign and malignant tumors. Nuclear medicine and MRI also show promise as primary diagnostic methods for evaluating the breast.

Some of the alternative imaging products now in testing also have a potential role to play in women's health. The exact nature of those roles, however, is not certain.

For the most part, alternative technologies are being designed to complement x-ray mammography, adding information but not standing on their own as screening or diagnostic modalities. Their positions in the diagnostic hierarchy may be less a matter of technological weakness than of the way medicine is practiced. To achieve an equal status with x-ray mammography, new technologies would have to prove their diagnostic abilities clinically. Tens or hundreds of thousands of patients might have to be examined. The cost and time to conduct such tests would be prohibitive.

Just gaining approval as an adjunct technology is proving hard enough. Imaging Diagnostic Systems, for example, was founded in 1993, had its first meeting with the FDA two years later, and began human trials in 1996. Some five years later, IDS is still gathering clinical data for a PMA application. The company caught a break in early January, when regulatory approval was granted to apply the CE Mark, clearing the way for sale of the laser-based system in certain European countries. Marketing approval in the U.S., however, could still be years away.

But even without commercial approval, adjunct technologies can exert a positive effect on healthcare and the imaging industry. They raise questions about current practices and push medical science to examine new possibilities.

"There may have to be some disruptive technologies like these that challenge the status quo but at the same time have a strong scientific foundation," said Philip C. Thomas, chief executive officer of DOBI. "That's the approach we're taking."