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Figure 1a. Focal island of normal tissue rated as BI-RADS category 1 at unblinded review and cited for recall by only one of five radiologists at blinded review. (a) Craniocaudal and (b) mediolateral oblique views in a 64-year-old woman show a focal region of normal-appearing glandular tissue (arrow) perceived on the mediolateral oblique view only. Note that the finding has lucent areas within it. Thirteen months later, (c) craniocaudal and (d) mediolateral oblique mammograms show a 1.0-cm suspicious mass (arrows) in the same location. Biopsy results indicated grade II invasive ductal carcinoma.