At ultrasonography (US), purely or predominantly echogenic breast masses are rare. These lesions were once assumed to be benign, but recent data suggest that approximately 0.5% of malignant breast lesions appear echogenic. However, correlation with the mammographic appearance, lesion location, and clinical history allows the need for biopsy to be determined. An echogenic mass that is radiolucent at mammography is benign. An echogenic mass that is not radiolucent at mammography may represent a hematoma, complex seroma, silicone granuloma, abscess, galactocele, or fat necrosis when the appropriate clinical history is present. In these cases, biopsy can usually be avoided. If there is a clinical history of cancer or radiation therapy, biopsy is often indicated to assess for metastasis or angiosarcoma. An echogenic mass in an ectatic duct warrants biopsy to exclude carcinoma. An echogenic skin lesion is most likely benign and can occasionally have peripheral vascularity due to surrounding inflammation. However, a skin lesion with internal vascularity is concerning for metastasis or lymphoma. If there is no suspicious clinical history, suspicious sonographic features or mammographic findings would lead to a recommendation for biopsy. Lesions with nonspecific imaging or clinical features (eg, angiolipoma or pseudoangiomatous stromal hyperplasia) may require biopsy to exclude malignancy.

© RSNA, 2013