To determine the degree of histologic sampling necessary for adequate examination of breast core needle biopsy specimens.
The results of all breast core needle biopsies (11 and 14 gauge) with a diagnosis of atypical small acinar proliferation or atypical ductal hyperplasia and subsequent excisional biopsies, for a 50-month period were reviewed. Blocks of all cores were sectioned entirely in 8 slides to determine the amount of sectioning needed to detect these foci, and the results were correlated with those from the excision specimen.
Large community hospital practice.
Of 3026 cases, 216 (7.1%) were diagnosed as atypical ductal hyperplasia or atypia not otherwise specified. Subsequent resections were available in 105 (49%) cases, and after review, 95 (92%) qualified as atypical ductal hyperplasia and 2 were determined to be atypical small acinar proliferations. The 2 small acinar proliferations were first detected on the second and fourth slides. Of the atypical ductal hyperplasia cases, 43% were detected on the first slide, 17% on the second, 23% on the third, 8% on the fourth, and 8% on the fifth. No lesions were initially detected after this level. Ductal carcinoma in situ was detected in the excision specimens from 1 case each of those detected initially on the fourth and fifth slides.
Five sections of breast core needle biopsy specimens are necessary to ensure that all atypical small acinar proliferations and atypical ductal hyperplasia lesions are sampled.