The horizontal breast CT scanner developed by the University of California, Davis, is now in clinical testing at the university’s medical center. The trial will enroll about 190 patients. From the press release:
A new breast screening technology that may be able to detect tumors earlier than mammography — without the need for uncomfortable breast compression — is being tested in patients at the University of California, Davis, Medical Center.
Developed at UC Davis, the machine is the first breast CT to reach clinical testing in a generation. An early prototype was tested in the 1970s, but abandoned as impractical.
“We think this technology may allow radiologists to routinely detect breast tumors at about the size of a small pea,” said John M. Boone, professor of radiology and biomedical engineering at UC Davis and the machine’s developer. “In contrast, mammography detects tumors that are about the size of a garbanzo bean. Tumor size at detection is one of the most important factors in determining breast cancer prognosis, so if we can detect smaller cancers and do so routinely, survival from this disease will improve.”
Unlike mammography, in which the breast is squeezed between two plates, the breast CT machine requires no breast compression.The patient lies face down on a padded table. The table has a circular opening in it, through which the patient places one breast at a time. A CT machine under the table scans each breast. The screening takes about 17 seconds per breast.
“There was no discomfort,” said Lydia Howell, a professor of pathology at UC Davis and a volunteer in preliminary clinical testing of the breast scanner. “But the more important advance will be if breast CT does detect tumors earlier than mammography. The earlier and smaller a cancer is when it is detected, the less the chance that it has spread to the lymph nodes, lungs or bones, and the greater the chance for a permanent cure and for breast preservation.”
A mammogram is an X-ray taken through all the layers of the breast at once. The resulting image may not detect a tumor hidden by other structures within the breast. This is more likely to happen in the case of young women with dense breasts or in women with breast implants.
The breast CT scanner takes images of virtual “slices” of the breast — about 300 images per breast. Computers then assemble these images into highly detailed, three-dimensional pictures that provide a more unobstructed view of breast tissues than can be seen on mammography…
If the trial confirms that breast CT detects tumors as well as mammography, as investigators expect, the next step will be a larger trial to determine whether the new technology can indeed detect tumors earlier than mammography. Boone believes that a more extensive trial could be under way within two to three years.