DR More Effective than CR in Breast Cancer Screening

Digital direct radiography (DR) detects more breast cancers than does computed radiography (CR), according to a study published in the journal Radiology.

Researchers from Prevention and Cancer Control at Cancer Care Ontario in Toronto, Canada, compared findings from DR, MR, and screen film mammography to assess their comparative effectiveness in breast cancer screening.

Anna M. Chiarelli, PhD, and her colleagues accessed the mammographies of 403,688 women in Ontario who had been screened between January 1, 2008, and December 31, 2009. Of these women, 220,520 underwent DR and 64,210 underwent CR. The rest underwent screen film mammography. The women were followed for 12 months following their screening.

The researchers found that DR detected 4.9 cancers per 1,000 mammograms, similar to screen film mammography findings, 4.8 per 1,000. Computed radiography only detected 3.4 cancers per 1,000 mammograms.

“CR was 21 percent less effective than DR,” Chiarelli said in a release. “This could result in about 10 fewer cancers detected per 10,000 women screened.”

Technical factors could account for some of the lower detection rates, the authors wrote; DR takes an electronic image of the breast that can be stored and sent electronically, while CR is an offline system. There could be a loss of spatial resolution or sharpness, or there could be increased image noise or granularity, Chiarelli noted.