Solid breast lesions: diagnosis with US-guided fine-needle aspiration biopsy.

PURPOSE: To ascertain the usefulness of real-time ultrasound (US)-guided fine-needle aspiration biopsy as an adjunct to clinical, mammographic, and sonographic assessment of solid breast lesions. MATERIALS AND METHODS: US-guided fine-needle aspiration biopsy was performed in 225 malignant and 580 benign solid breast lesions confirmed by means of excisional biopsy or with imaging follow-up (mammography or US) performed at approximate intervals of 6, 12, 24, and 36 months. All lesions were classified as palpable or nonpalpable at clinical examination and visible or nonvisible on mammograms. RESULTS: In 213 malignant lesions (95%), the cytologic findings were malignant or suspicious, with no false-positive and 12 false-negative cases. Mammography did not enable detection of 58 cancers (26%), 43 of which were palpable. Fifteen cancers discovered with US were nonpalpable and not seen on mammograms. Cytologic diagnosis of fibroadenoma or nonspecific benign cells was correct in 535 lesions. The sensitivity of this method was 95%; specificity, 92%; and overall accuracy, 93%. CONCLUSION: Real-time US-guided fine-needle aspiration biopsy is a useful adjunct to clinical, mammographic, and sonographic assessment of solid breast lesions.