Stereotaxic 14-gauge breast biopsy: how many core biopsy specimens are needed?

Overview

PURPOSE: To determine the optimum number of specimens to obtain at stereotaxic core breast biopsy. MATERIALS AND METHODS: Stereotaxic biopsies were performed in 145 mammographically evident lesions by using a dedicated table with patients in the prone position. Samples were obtained with an automated gun and a 14-gauge needle. Indications for biopsy were calcifications (n = 53) and masses (n = 92). Three to 11 (mean, 5.4) core biopsy specimens were obtained per lesion and were analyzed separately. RESULTS: Diagnostic material was obtained in the first specimen in 102 (70%) of the 145 lesions. Obtaining two, three, four, five, and six core specimens yielded a diagnosis in 117 (81%), 129 (89%), 132 (91%), 137 (94%), and 140 (97%) of the 145 lesions, respectively. Obtaining five specimens yielded a diagnosis in 46 (87%) of the 53 calcifications and 91 (99%) of the 92 masses. Obtaining six specimens resulted in a diagnosis in 49 (92%) lesions evident as calcifications but did not improve the yield on masses. CONCLUSION: Stereotaxic 14-gauge core biopsy achieved a 99% diagnostic yield with five specimens for masses. Additional specimens may be necessary to diagnose some calcified lesions.