Sonographic appearance and ultrasound-guided fine-needle aspiration biopsy of breast carcinomas smaller than 1 cm3.

The purpose of this study was to review the sonographic appearance and the results of ultrasound-guided fine-needle aspiration biopsies of a series of 49 breast carcinomas smaller than 1 cm3. No tumor was found to be hyperechoic. Contours were irregular in 69% of cases. In 53%, an echogenic rim was present, and the echotexture was nonhomogeneous in 41%. Sound beam attenuation was present in 39%. The ratio of longitudinal diameter to anteroposterior diameter ranged from 0.67 to 2.25 (mean, 1.08 +/- 0.28). Fine-needle aspiration biopsy under continuous real-time sonographic guidance was performed on 36 patients and yielded 30 positive and four suspicious results (sensitivity, 94%), one inadequate specimen, and one false-negative result. With high-resolution hand-held transducers, breast sonography can depict small carcinomas and provides accurate, cost-effective guidance for fine-needle aspiration biopsy.