Purpose: To determine whether systematically evaluated criteria for probably benign lesions were actually applied to lesions placed into that category.
Materials and methods: A search of the mammography database yielded 295 cases that were initially followed up with short-term interval mammography but eventually received a biopsy recommendation for the same breast. Of the 83 malignancies (81 patients) for which mammograms and pathology reports were available for review, 51 malignancies corresponded to the lesions for which short-term follow-up was recommended. Each case was retrospectively reviewed to determine whether the lesion followed up represented the subsequently diagnosed malignancy. Each lesion was characterized with appropriate Breast Imaging Reporting and Data System descriptors, based on the mammographic imaging available when short-term follow-up was first recommended. These characteristics were then used to determine if, in retrospect, the mammographic appearance met previously published criteria for probably benign lesions.
Results: Of the 51 malignancies, 23 (45%) appeared mammographically as microcalcifications, 12 (24%) as masses, four (8%) as architectural distortion, and 12 (24%) as developing densities. None fulfilled strict criteria for a probably benign lesion when reviewed in retrospect. Forty-seven (92%) of 51 lesions had already demonstrated progression at the time of follow-up recommendation.
Conclusion: Short-term mammographic follow-up is often recommended for lesions that, in retrospect, do not fulfill established diagnostic criteria for probably benign lesions.