SUNDAY, Dec. 31, 2006 (HealthDay News) -- The mammogram is changing for the better.
New computer-driven technologies should make the yearly exam more accurate and easier on patients than ever before, experts say.
High-tech computer-based digital mammography is already available at about 10 percent of diagnostic centers in the country and growing steadily at a rate of about 4 percent a month, said Priscilla F. Butler, senior director of the American College of Radiology Breast Imaging Accreditation Programs.
While filmless mammography doesn't feel any different to women while they are being screened, doctors are discovering that there are benefits for particular patients.
A study of more than 40,000 women published last fall found that compared with standard mammograms, computer-based digital "pictures" were more beneficial for more than half the women.
The findings of that study, the American College of Radiology Imaging Network Digital Mammographic Imaging Screening Trial, were that younger women with dense breast tissue, those under 50 and those who are premenopausal, would benefit most from digital mammograms. The range was so large that some doctors have since concluded that dense breast tissue in all groups is better seen with the help of a computer.
"In other situations, it is probably no different [to film]," said Dr. Carl D'Orsi, co-chairman of the American College of Radiology Breast Imaging Commission and professor of radiology and director of the Breast Imaging Center at Emory University in Atlanta.
Other technologies are on the horizon.
In late November, researchers presenting at the Radiological Society of North America's annual meeting, in Chicago, created buzz by announcing data on a new technology called Cone Beam Breast Computed Tomography (CBBCT). According to experts, CBBCT promises to equal or surpass mammography in detecting breast cancer, and it does so without squeezing the breast in a vice.
The CBBCT scanner takes a number of pictures of the breast from various angles then merges them into one three-dimensional image. The system was developed by a professor at the University of Rochester, which holds several patents on the technology. The university licensed the technology to Koning Corp. to make, use and sell the scanners. The National Cancer Institute, along with private investors, helped fund the development of the scanner.
This pilot study used the CBBCT scanner to image 20 volunteers who had had normal mammograms, as well as a group of women who had had abnormalities detected during a physical exam or who had had suspicious mammograms. The goal of the study was simply to see how well the CBBCT could image the breast.
The CBBCT proved itself at least as good as conventional mammogram in imaging the breast, the study's authors concluded.
The system also has the advantage of being more comfortable. The woman lies on her stomach on a cushioned exam table with a cutout in the middle. She suspends her breasts one at a time through the cutout while the CBBCT takes 300 images in the space of about 10 seconds. The radiation dose is comparable to that of mammography. Unlike conventional mammography, the CBBCT system clearly displays tissue around the ribs and outer breast near the armpits.
The pilot study will continue until 60 participants have been imaged. A larger trial is planned for next year.
Koning Corp. hopes to have a commercial scanner on the market as soon as the U.S. Food and Drug Administration approves the device. But other technologies may be further along, said Dr. Joshua Kalowitz, chief of breast imaging at Maimonides Cancer Center in New York City.
"There's a lot of new stuff on the horizon," he said. "Five years from now, we'll be in a lot better shape, but right now, we have to see which ones will end up being the best."
Computerized mammography does have its drawbacks -- at least for now. D'Orsi said there are so many options for setting up and reading the computer images that doctors are somewhat slower at determining their results.
"You have the ability to manipulate the image, invert it, adjust the brightness, which you can't do with film, so it may take longer," he said. "There's a learning curve to it because it's new, but you get faster and faster."
He's excited by the technology, which will soon make it possible to "see" tissue in ways that film and the naked eye cannot.
"We can invent novel new technologies," he said, among them a three-dimensional approach that will improve cancer detection. Already in the works are what he calls a "computerized method of peeling layers of breast away electronically," so that irregularities can be pinpointed more exactly.
And, as doctors and hospitals adapt to electronic patient charts, digital mammography will play an important role, said Butler. "Mammography was one of the last holdouts in going to a filmless environment, which is much more efficient," she said. "All of medicine is pretty excited about it."
But D'Orsi cautions that the most important thing is not the technology itself, but the person reading the results.
And, the National Cancer Institute warns women not to wait for the new technology. The guidelines in place for several years still apply:
- Women in their 40s should have mammograms every one to two years.
- Women 50 and older should be screened every one to two years.
- Women who are at higher than average risk of breast cancer should seek expert medical advice about whether they should begin screening before age 40 and the frequency of screening.
More information
For more on digital mammography, visit the National Cancer Institute.
