Vacuum-assisted stereotactic breast biopsy - Histologic underestimation ofmalignant lesions

Hypothesis: The histopathologic correlation between stereotactic core needl e biopsy and subsequent surgical excision of mammographically detected nonp alpable breast abnormalities is improved with a larger-core (11-gauge) devi ce. Design: Retrospective medical record and histopathologic review. Setting: University-based academic practice setting. Patients: Two hundred one patients who underwent surgical excision of mammo graphic abnormalities that had undergone biopsy with an 11-gauge vacuum-ass isted stereotactic core biopsy device. Main Outcome Measure: Correlation between stereotactic biopsy histologic re sults and the histologic results of subsequent surgical specimens. Results: Results of stereotactic biopsy performed on 851 patients revealed atypical hyperplasia in 46 lesions, ductal carcinoma in situ (DCIS) in 89 l esions, and invasive cancer in 73 mammographic abnormalities. Subsequent su rgical excision of the 46 atypical lesions revealed 2 cases of DCIS (4.3%) and 4 cases of invasive carcinoma (8.7%). Lesions diagnosed as DCIS on ster eotactic biopsy proved to be invasive carcinoma in 10 (11.2%) of 89 patient s on subsequent excision. Stereotactic biopsy completely removed 21 (23.6%) of 89 DCIS lesions and 20 (27.4%) of 73 invasive carcinomas. Conclusions: In summary, 11-gauge vacuum-assisted core breast biopsy accura tely predicts the degree of disease in the majority of malignant lesions; h owever, understaging still occurs in 11% to 13% of lesions showing atypical hyperplasia or DCIS.