Stereotactic core biopsy of nonpalpable breast lesions.

We report our experience with stereotactic core breast biopsies (SCBB) for mammographically suspicious, nonpalpable breast lesions. Ninety-seven patients, ages 29 to 94 (mean 57.3 years) underwent SCBB with a 14-gauge Biopty gun. A mean of 5.0 cores was taken from each lesion. Lesions were mammographically categorized by suspicion (high, > 60% chance of malignancy; intermediate, 25-60%; low, < 25%) and according to lesion character (well-defined mass, indistinct mass, spiculated mass, asymmetric density, and clustered microcalcifications [CM]). Histologic and radiographic findings were correlated at the time of biopsy and again retrospectively, with 92 percent correlation and eight percent partial or non-correlation. Of the latter, five of eight lesions represented CM not seen in the histologic samples. Of the 97 sampled lesions, 72 (74%) had been radiographically categorized as low suspicion, 10 (10%) as intermediate, and 15 (16%) as high. The procedure saved 74 women (76%) from open biopsy and added a diagnostic procedure for eight women (8%). Fifteen women (15%) went directly to mastectomy; therefore, the SCBB neither added nor saved a procedure for patients with cancer. Of the 72 lesions categorized as low suspicion, 65 (90%) were potentially saved from open biopsy, while nine of 25 lesions (36%) in the intermediate and highly suspicious groups were potentially spared a procedure. There were no false positive or negative cases among those who had an additional procedure or follow-up. The diagnoses made on SCBB included 15 carcinomas, one case each of atypical ductal and atypical lobular hyperplasia, one reactive lymph node, one intraductal papilloma, one collagenous spherulosis, one membranous fat necrosis, and numerous cases of fibrocystic change and fibroadenoma. In conclusion, we believe that this SCBB method can be an accurate and cost-effective tool in the management of these lesions.