Digital mammography screening: weighing reduced mortality against increased overdiagnosis

Prev Med. 2011 Sep;53(3):134-40. doi: 10.1016/j.ypmed.2011.06.009. Epub 2011 Jun 21.


Objective: Digital mammography has been shown to increase the detection of ductal carcinoma in situ (DCIS) compared to screen-film mammography. The benefits and risks of such an increase were assessed.

Methods: Breast cancer detection rates were compared between 502,574 screen-film and 83,976 digital mammograms performed between 2004 and 2006 among Dutch screening participants. The detection rates were then modeled using a baseline model and two extreme models that respectively assumed a high rate of progression and no progression of preclinical DCIS to invasive cancer. With these models, breast cancer mortality and overdiagnosis were predicted.

Results: The DCIS detection rate was significantly higher at digital mammography (1.2 per 1000 mammograms (95% C.I. 1.0-1.5)) than at screen-film mammography (0.7 per 1000 mammograms (95% C.I. 0.6-0.7)). Consequently, 287 (range progressive- non progressive model: 1-598) extra breast cancer deaths per 1,000,000 women (a 4.4% increase) were predicted to be prevented. An extra 401 (range: 165-2271) cancers would be overdiagnosed (a 21% increase).

Conclusion: Modeling predicted that digital mammography screening would further reduce breast cancer mortality by 4.4%, at a 21% increased overdiagnosis rate. The consequences of digital screening, however, are sensitive to underlying assumptions on the natural history of DCIS.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Breast Neoplasms / diagnosis*
  • Breast Neoplasms / mortality
  • Carcinoma, Intraductal, Noninfiltrating / diagnosis*
  • Carcinoma, Intraductal, Noninfiltrating / mortality
  • Confidence Intervals
  • Diagnostic Errors*
  • Disease Progression
  • Early Detection of Cancer / instrumentation
  • Early Detection of Cancer / methods*
  • Female
  • Humans
  • Incidence
  • Mammography / instrumentation*
  • Mammography / methods
  • Middle Aged
  • Netherlands
  • Risk Assessment / methods