Researchers study system designed for diagnosis as way to treat disease
FRIDAY, July 31 (HealthDay News) -- Breast computed tomography (CT) scans, already used experimentally to diagnose breast cancer, may also be able to treat it, a California researcher reports.
"Breast CT is superior to mammography for [detecting] masses," said John Boone, vice chair of research radiology at the University of California Davis. He presented information about the potential of breast CT for treatment this week at the American Association of Physicists in Medicine meeting, in Anaheim, Calif.
Since 2004, Boone has led a group of UC Davis researchers in developing the breast CT scan for diagnosing breast cancer in women. The technology's pluses, said Boone, include being more comfortable than conventional mammograms but just as safe.
More than 200 women have been scanned with the custom-designed breast CT prototype scanner, he said. The technology has not yet made its way into clinical practice, he said, but preliminary results look good. "Breast CT is still experimental for diagnosis," he said. But it is already looking to be more effective than traditional mammography at detecting breast masses.
More work needs to be done to find microcalcifications, tiny specks of calcium which don't always mean cancer is present but bear checking, he added.
Next, Boone hopes to use the breast CT scanner to guide interventional procedures such as a robotic biopsy, radiofrequency ablation and cryoablation to treat breast cancer.
With the breast CT scanner, a woman lies on her stomach, face down on the table while the breast drops through a hole in the table; the CT scanner then rotates around the breast. The position is considered more comfortable, especially for big-breasted women.
Boone hopes that the new scanner could be used to perform image-guided therapies such as the technique known as radiofrequency ablation. "It literally heats up the tissue, cooks the tumor and kills the tumor," he said. It may help some women avoid lumpectomy and follow-up radiation therapy.
"The concept is good," said Dr. Chika Madu, an assistant professor of radiation oncology at Georgetown University Hospital in Washington, D.C.
But she added a caveat that the energy level talked about by Boone may have to be adjusted. "It may come at a price of increased toxicity to the skin," she noted.
The technique may not work for all cancers or all women, she added. "In small-breasted women, not enough breast may come through the hole sufficiently [to treat]," she said. Cancer that is close to the chest wall rather than the nipple may not be treatable by this technique either, she said.
Even so, Madu said, "I think it's worth exploring."
Boone's study was funded partially by the industry, including Varian Medical Systems, Fuji Medical Systems and Hologic Corp.
In another presentation at the same meeting, Michael O'Connor, a professor of radiologic physics at the Mayo Clinic in Rochester, Minn., reported on molecular breast imaging (MBI), a new technique that uses gamma cameras designed for breast imaging.
"The devices look somewhat like a mammography unit," he said. A small amount of radioisotopes is given intravenously and is taken up by any tumors in the breasts, he said.
In a study of 1,000 patients, mammography picked up three cancers but MBI picked up 10, he said.
Next, O'Connor hopes to reduce the dose of radioisotopes and begin a clinical trial. The technique is expected to especially benefit women with dense breasts, for whom mammography is not as accurate at cancer detection.
Efforts to find ways to detect small cancers that can't be felt on exams should be stepped up, said Dr. Gary Whitman, a professor of radiology at M.D. Anderson Cancer Center in Houston. Other studies suggest MBI has promise, he said, but O'Connor's finding "would need to be confirmed."
To learn more about early detection of breast cancer, visit the American Cancer Society.
SOURCES: Michael O'Connor, Ph.D., medical physicist and professor, radiologic physics, Mayo Clinic, Rochester, Minn.; Gary Whitman, M.D., professor, radiology, M.D. Anderson Cancer Center, Houston; Chika Madu, M.D., radiation oncologist and assistant professor, radiation oncology, Georgetown University Hospital, Washington, D.C.; John M. Boone, Ph.D., professor and vice chair, research radiology, and professor, biomedical engineering, University of California Davis; July 28, 2009, presentations, American Association of Physicists in Medicine annual meeting, Anaheim, Calif.
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