Evaluation of frozen sections in grossly benign breast biopsies

Breast biopsies have traditionally been one of the most common specimens submitted for frozen section. However, many breast biopsies now consist of fibrofatty tissue with no areas grossly suspicious for malignancy. Because some physicians have criticized the routine use of frozen sections in such specimens, the usefulness of frozen sections performed on grossly benign breast biopsies was evaluated. Four hundred thirty-two consecutive breast biopsies having frozen sections were studied. Of these, 167 (38.7%) showed a mass by gross examination. The remaining 265 contained no areas grossly suspicious for neoplasia. Frozen-section diagnosis was deferred in seven of these cases, with the other 258 reported as benign. Ten of these 258 (3.9%) had small areas of in situ or invasive carcinoma diagnosed on permanent sections; seven of these lesions were not present on the frozen section slide. Twelve (4.7%) had areas of atypical hyperplasia (10 ductal, two lobular) identified only on permanent sections. This study indicates that frozen sections done on breast biopsies that are grossly benign do not add to the gross impression, and may be misleading mostly because of the false-negative rate.