A prospective study of 4,341 consecutive screening mammograms found that CAD increases the cancer detection rate by 5.4%, said Priscilla Slanetz, MD, MPH, director of breast imaging at Caritas St. Elizabeth's Medical Center, Boston, MA, a teaching affiliate of Tufts University School of Medicine. "This number is probably lower than what other facilities might see because the radiologists reading the images at our facility are very experienced. Because they are experienced mammographers they are less likely to miss cancers that are then picked up by CAD," said Dr. Slanetz. Previous studies have shown that double reading (having a second radiologist review the mammograms) picks up between 5% and 15% more cancers, she noted.
The study found that CAD missed 11 of 38 cancers, particularly those that presented as architectural distortion or those which were asymmetric and low in x-ray attenuation; however, CAD was very precise in detecting calcifications, said Dr. Slanetz. The radiologists missed two cases of faint calcifications that were detected by CAD. One cancer case was missed by both, said Dr. Slanetz.
The recall rate (the chance a screening patient is called back for additional imaging evaluation) went from 11.5% without CAD to 13.4% with CAD, said Dr. Slanetz. This is not a significant increase, she added.
The results of this study indicate that CAD is an effective way to double-read mammograms without the need for a second radiologist. This is especially important since the demand for mammography continues to increase (more and more women are being screened as the baby boomers age), while there is a decrease in manpower (an increase in mamm
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American Roentgen Ray Society