Stereotactic breast biopsy in a community hospital setting

Our institution began using a stereotactic core needle breast biopsy system for mammographically detected breast lesions in November 1996. The system consists of a LORAD stereo imaging table and an 11-gauge vacuum-assisted mammotome (Biopsys Medical, Irvine, CA). All biopsies were performed with the combined efforts of a radiologist and a surgeon. Three hundred sixteen biopsies were attempted in 279 patients, with multiple biopsies in 31 patients. Indications included microcalcifications in 52 per cent of patients and a mass in 48 per cent of patients. Biopsy was unsuccessful in 20 patients (6.3%). Pathologic diagnoses included invasive ductal carcinoma (19 patients), invasive lobular carcinoma (2), ductal carcinoma in situ (17), atypical ductal hyperplasia (8), atypical lobular hyperplasia (1), fibroadenoma (40), lymph node (7), and benign (202). Invasive cancer, in situ carcinoma, or atypical hyperplasia was diagnosed in 46 (15.6%) lesions. Thirty-six patients had open biopsies. The core biopsy diagnosis was correct in 27 lesions, unable to be confirmed in six cases and changed in four cases, with three lesions upgraded and one case downgraded. The 11-gauge vacuum-assisted mammotome provides excellent accuracy for diagnosing mammographic abnormalities. A combined effort between radiology and surgical services is an effective way of using the stereotactic biopsy system.