The next breast thing
It’s a call that any woman dreads. The results from her recent mammogram are back, and something has shown up that needs further investigation.
The callback produces anxiety and leads to another round of expensive screening tests.
Or for other women, particularly those with dense breast tissue, mammography may fail to detect a cancer altogether.
“With mammograms, it is sometimes hard to pick up breast cancer because we are putting a three-dimensional structure on a flat screen,” says Emory radiologist Mary Newell. “We can miss cancers that are there or see things that aren’t really there.”
Enter a new technology—computed tomography (CT) scans of the breast. These new prototype CT scanners use cone-shaped X-ray beams combined with a digital flat panel detector to produce 3D images.
During the exam, a woman lies prone on a table, allowing the breast to hang through a hole rather than being squeezed between flat panels as in traditional mammography. Below the table, an x-ray source and detector rotate around the breast. The 10-second scan gathers digital information that produces hundreds of images.
Emory is one of only three sites in the United States testing the dedicated CT breast scanner manufactured by Koning Corporation. Emory radiologists Carl D’Orsi and Mary Newell are evaluating breast CT scans compared with diagnostic mammography as a tool for detecting cancer. In a second clinical trial, they are comparing breast CT scans (enhanced with contrast dye) with MRI to characterize newly diagnosed breast cancers. And in a third study, the researchers are looking at the effectiveness of breast CT scans in detecting how tumors are responding to chemotherapy treatments.
Newell believes the ability to tell whether a cancer is responding to a particular treatment is one of the most important potential applications for the new technology. “A doctor’s hand exam is not as sensitive or specific as the dedicated CT scan may prove to be.”
With the dedicated CT breast scanner, the researchers can reconstruct the breast from any angle, top down, and side-to-side. Computer post-processing allows them to focus in on calcifications, digitally remove the nipple or unnecessary background features, and manipulate the image in any way to sort out a real or false finding.
Dedicated breast CT may end up being used alone for routine screenings or in combination with other technologies for cancer diagnosis and treatment, says Newell. “The goal is to figure out the best way to see the breast in 3D. We think we’re moving in the right direction.”—Rhonda Mullen