Value of Hand-held Ultrasound in the Differential Diagnosis and Accurate Breast Imaging Reporting and Data System Subclassification of Complex Cystic and Solid Breast Lesions.

To explore the value of hand-held ultrasound (HHUS) for diagnosing complex cystic and solid breast lesions, 472 pathologically proven lesions were analyzed. The lesions were divided into four types based on ultrasound features. Positive predictive values (PPVs) for lesion types and risk factor performances were assessed. Furthermore, HHUS and mammography (MAM) performances were compared: 27 lesions missed in MAM were detected in HHUS. Ultrasound feature analysis revealed higher PPVs for type III and IV lesions than for type I and II lesions. In patients older than 51 y, a type III or IV lesion with a diameter greater than 18 mm, an irregular shape, a non-parallel orientation, an uncircumscribed margin, calcification, vascularity and abnormal axillary lymph nodes were suggestive of malignancy; the area under the curve reached 0.869. Thus, ultrasound is useful in diagnosing complex cystic and solid breast lesions, which should be categorized as Breast Imaging Reporting and Data System (BI-RADS) 4B or 4C.