Computed assisted detection of interval breast cancers

Objectives: To examine interval cancer detection rate for a system of compu ter assisted detection (CAD) and its influence on radiologists' sensitivity /specificity in a screen-like retrospective review situation, Materials and methods: Three screening radiologists reviewed previous screen images of 5 9 interval cancers mixed with other screening mammograms (ratio 1:5) and no n-mixed. Mixed interval cases were interpreted both without and with aid of CAD. Results: CAD detected a number of 14 interval cancers while the three radiologists detected 17, 12 and 11 without and 16, 10 and 13 with CAD. Al though CAD specificity was low (38%) no reduction in radiologists' specific ity occurred using CAD (73%, 82% and 89% without and 78%, 90% and 92% with CAD). Non-mixed reading increased radiologists' detection rate to 21, 17 an d 19 interval cancers respectively. Conclusion: Despite sufficiently high s ensitivity for CAD alone no increase in radiologist sensitivity (or decreas e in specificity) occurred with CAD. Improving CAD specificity, with unaffe ctedly high sensitivity, should make radiologists more inclined to revise i nterpretations according to CAD. The potential sensitivity increase, noted when using CAD as a double reader, could be realised in this way. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.