Does computer-aided detection (CAD) contribute to the performance of digital mammography in a self-referred population?

BACKGROUND: Recent evidence suggests that computer-aided detection (CAD) may have a negative impact on the interpretation of mammography-this necessitates timely evaluation of CAD in practice. We report a retrospective study of the incremental effect of CAD on the accuracy of full-field digital mammography (DM) as applied prospectively in breast assessment. METHODS: Subjects were all consecutive women attending a self-referral breast centre in Florence between September 2005 and January 2007 (N = 3,425). DM was reported without, then with, CAD according to a standard protocol; all mammograms recalled on the basis of either the radiologist's reading alone, or the radiologist's reading after viewing CAD, were recalled to assessment. RESULTS: Overall recall rate (RR) was 13.1% and 107 cancers were diagnosed (90 invasive cancers, 8 DCIS, 9 malignant on cytology). The use of CAD allowed the additional detection of 5 cancers (three invasive cancers, one DCIS, one malignant on cytology) and caused one additional benign surgical biopsy, with a relative RR of 4.9%, and an incremental RR of 1.17%. The cancer detection rate (CDR) of DM interpreted with the use of CAD was 3.12% and did not significantly differ from the CDR of 2.9% based on DM without CAD (chi(2) = 3.2, P = 0.07). CONCLUSION: While the increase in CDR with the use of CAD only approached statistical significance, representing modest gains in absolute terms, the incremental number of cancers detected justifies the incremental recall and benign surgical biopsy attributable to CAD use. In our clinical setting, these data suggest more benefit than harm in using CAD with DM, and we will continue the use of CAD with ongoing monitoring of patient outcomes.

Negligible advantages and excess costs of routine addition of breast ultrasonography to mammography in dense breasts.

AIM: To assess the role of breast ultrasonography as a complement to negative mammography in radiologically dense breasts. MATERIAL AND METHODS: Out of a total series of 49,044 consecutive mammograms reported as negative in asymptomatic women, 25,665 (52.3%) were coded as dense (BI-RADS D3-4) and ultrasonography was recommended. Due to organizational problems, ultrasonography was performed immediately or within 1 month only in 5,227 cases, representing the study series. RESULTS: Two cancers were detected at immediate ultrasonography (0.03%). The cancer detection rate in women aged 40-49 and 50-69 years was 0.002% and 0.07%, respectively. The benign biopsy rate was 0.5% for core biopsies and 0.02% for surgical biopsies. The cost per ultrasonography-assessed woman was Euro 56.05, whereas the cost per additional mammographically occult but ultrasonography-detected cancer was Euro 146,496.53. The mammograms of the 2 cancer cases underwent blind review by an expert reader and were confirmed as negative. DISCUSSION: Our findings show a low cancer detection rate, substantially lower compared to other clinical studies of ultrasonography in dense breasts, though in accordance with preliminary evidence from an Italian randomized clinical trial within a population-based screening program. The policy of adding ultrasonography to negative mammography in dense breasts seems to have very limited cost-effectiveness, and should not be adopted in routine practice before results of ongoing clinical trials are available.