Evaluation of nonpalpable solid breast masses with stereotaxic large-needle core biopsy using a dedicated unit

In our institution for the past 4 years, stereotaxic core breast biopsy using a 14-gauge needle has been offered as an alternative to surgical excision. The purpose of this paper is to describe our protocol, results, and lessons learned from our experience.

From August 1991 to July 1995, 388 stereotaxic needle core biopsies of clinically occult, noncalcified, mammographically detected solid masses were performed. In this group, 103 patients underwent subsequent surgical excision. Another 169 have had follow-up examinations 1 year or more after their biopsies.

Of the 61 patients diagnosed with a malignant process on core biopsy, all had confirmation on subsequent surgical excision. Forty-one of the 42 core biopsies that showed a benign process were subsequently confirmed on surgical excision. One patient with atypical ductal hyperplasia on core biopsy had ductal carcinoma in situ on surgical excision. Patients with 169 benign masses on core biopsy have been followed for at least 1 year by mammography. Of these women, 110 have been followed for at least 2 years, and no malignant lesions have been found.

Stereotaxic large-needle core biopsy appears to be an accurate alternative to surgical excision for evaluating a solid breast mass. However, the mammographic appearance, technical quality of the biopsy, and pathologic findings in each patient must be correlated to ensure the highest possible accuracy when using this technique.