Mammography more effective when compared to previous screenings

According to researchers at the University of California, the recall rate of screening mammography is greatly reduced when physicians compare present and past mammograms.

In a paper published in the American Journal of Roentgenology, a research team led by Kimberly M. Ray, a radiologist with the department of radiology and biomedical imagining, University of California, San Francisco, analyzed 46,288 consecutive screening mammograms from 22,797 patients.

The results categorized as 1) those without a comparison with prior mammograms, 2) those with comparison to one prior test or 3) those compared with two or more tests. Results showed that the recall rate for the non-comparison group was 16.6 percent, 7.8 percent for the one comparison group and 6.3 with two or more comparisons.

"Consequently, although the reduced mortality rate associated with screening mammography arguably far outweighs the potential harms of the examination, a reduction in false-positive results should be a priority to ensure that support for and access to screening mammography are maintained," said Ray et al. "Because millions of women undergo screening mammography each year in the United States, even a small reduction in the recall rate may result in a widespread benefit."

Evidence suggests mammography can reduce breast cancer mortality among women 40 years and older by as much as 40 percent. But false positives can lead to cause patient anxiety and additional radiation exposure and biopsies.

"Our findings suggest that radiologists who make comparisons with more than one prior examination at screening mammography will have more true-positive outcomes and fewer false-positive outcomes," said Ray. "We have shown that the recall rate for screening mammography decreases, whereas the positive predictive value of recall and the cancer detection rate increase when two or more prior examinations are used for comparison relative to comparison with a single prior examination.”