Current status of breast ultrasound.

Ultrasound (US) has a significant role in diagnostic breast imaging. It is most commonly used as an adjunctive test in characterizing lesions detected by other imaging modalities or by clinical examination. US is recognized as the modality of choice in the evaluation of women who are symptomatic and younger than 30 years of age, pregnant, or lactating. Combined mammography and US appear to have a role in screening high-risk populations. The use of standard Breast Imaging Reporting and Data System US lexicon is helpful in guiding the differentiation between benign and malignant sonographic signs. Biopsy is warranted when benign features are absent or for any feature consistent with malignancy, despite other benign findings. Whole breast and axillary US are useful in assessing tumour extension, multifocality, and the status of axillary lymph nodes. US is the modality of choice for guiding interventional breast procedures. The role of US as a guidance tool for nonoperative breast treatment is being investigated.