Computer-aided Detection in Full-field Digital Mammography: Sensitivity and Reproducibility in Serial Examinations

Purpose: To retrospectively evaluate the sensitivity and reproducibility of a computer-aided detection (CAD) system applied to serial digital mammograms obtained in women with breast cancer, with histologic analysis as the reference standard.

Materials And Methods: This study was institutional review board approved, and patient informed consent was waived. A commercially available CAD system was applied to initial and follow-up digital mammograms obtained in 93 women with breast cancer (mean age, 52 years; age range, 32-81 years). The mean interval between mammographic examinations was 23 days (range, 7-58 days). There were 119 visible lesion components (70 masses, 49 microcalcifications). Sensitivity, false-positive mark rate, and reproducibility of the CAD system were evaluated for both sets of mammograms with the t test.

Results: Sensitivities of the CAD system at initial and follow-up digital mammography were 91% and 89%, respectively, for detection of masses. Sensitivity of the CAD system for detection of microcalcifications was 100% at both initial and follow-up digital mammography. Overall false-positive mark rates were 0.29 per image and 0.27 per image at initial and follow-up digital mammography, respectively. When craniocaudal and mediolateral oblique views were considered separately, sensitivities were 76% and 75%, respectively, for masses and 96% and 92%, respectively, for microcalcifications. The reproducibility of CAD marks was 80% for true-positive masses, 92% for true-positive microcalcifications, 9% for false-positive masses, and 8% for false-positive microcalcifications (P < .001).

Conclusion: The sensitivity of the CAD system was consistently high for detection of breast cancer on initial and short-term follow-up digital mammograms. Reproducibility was significantly higher for true-positive CAD marks than for false-positive CAD marks.

Supplemental Material: http://radiology.rsnajnls.org/cgi/content/full/246/1/71/DC1.