CAD Helps Detect
Smaller, Potentially More Aggressive Breast Cancers in Younger Women
Behind the Cancer Headlines®
A computer-aided detection system not only helps radiologists detect more breast cancers, but also helps detect smaller tumors in younger women, a new study shows.
The study included 27,274 screening mammograms done over a
three-year period: 19,402 were done using a computer-aided mammography
detection system (CAD), and 7,872 were mammography studies done before the CAD
system was installed, said Tommy E. Cupples, MD of ImageCare, LLC in Columbia, SC, and the lead author of the
study. The study was conducted at the
"Overall, we saw a 16% increase in the cancer detection rate," said Cupples. But the increased detection rate doesn't tell the whole story, he said. "The more important question is do we find more cancers earlier, when they are smaller and most curable." CAD increased the detection rate of small invasive cancers (those 1 cm or less) by 164%, said Cupples. "Invasive, lump forming cancers are more likely to be lethal if they aren't detected early, especially in younger women," he said. "The average age of mammography screening detected cancers in the CAD group was more than five years younger than in the pre-CAD group," Cupples said.
In the study, published in The American Journal of Roentgenology, the radiologists reviewed each mammogram and then activated the CAD system. The CAD system "marked" areas on the mammogram that were suspicious for cancer, then the radiologists would again review the mammogram. "The CAD system we used was particularly useful for finding small masses," said Cupples. "Small masses are difficult for radiologists to detect, especially in younger women with denser breast tissue. The CAD system is an excellent addition to the radiologist's expertise," he said.
The recall rate – the rate at which
patients were called back for additional studies or a biopsy – was 7.71% in the
pre-CAD group and 8.34% in the CAD group. A recall rate of less than 10%
is considered to be acceptable, Cupples said. The
biopsy rate increased from 1.37% in the pre-CAD period
to 1.47% in the CAD period. "The increase in the detection of smaller
cancers more than made up for the increase in the recall and biopsy rate,"
Cupples added.
SOURCES:
The American Journal
of Roentgenology, October 2005
The American Roentgen Ray Society (http://www.arrs.org)