Practice Makes Perfect

Radiologists who read more mammograms tend to be better at determining which suspicious breast lesions are cancer, according to a new report from the Institute of Medicine.

As a result, the Institute -- the health arm of the National Academies -- has called for more research on the associations between volume and performance in screening mammography.

The study looked at information from 120 radiologists, who interpreted 783,965 screening mammograms over a five-year period at six mammography registries in the Breast Cancer Surveillance Consortium (BCSC). In particular, researchers focused on how screening outcomes looked when compared to different annual volumes from four separate radiologists.

Study leader Diana S.M. Buist, PhD, MPH, a senior investigator at Group Health Research Institute said the researchers found that radiologists who interpreted more mammograms per year missed fewer cancer diagnoses and had fewer false-positive findings.

Current guidelines from the U.S. Food and Drug Administration (FDA) require mammographers to interpret only 960 mammograms every two years. These requirements are as many as 5 times higher in Europe and Canada, where false-positive results are less frequent than in the United States but cancer-detection rates are similar.

False-positive results require further testing (to the tune of $1.6 billion annually) and cause undue anxiety in patients. This study shows that if the U.S. could reduce the false-positive results it would not only save the U.S. $1.6 billion annually, it would save a lot of worry for patients.