Acta Academiae Medicinae Sinica

Abstract: Objective To evaluate the diagnostic value of the sonographic features of Breast Imaging Reporting and Data System(BI-RADS)assessment category 4 and 5 non-palpable breast lesions. MethodsA total of 213 non-palpable breast lesions that were pre-operatively assessed to be BI-RADS category 4 and 5 lesions by ultrasound were enrolled in this study. The diagnostic value of their sonographic features were assessed by using pathologic results as the golden standards. ResultsOf these 213 lesions, 128(60.1%)were pathologically confirmed to be benign and 85(39.9%)to be malignant. The mean size was not significantly different between the benign and the malignant lesions（P=0.09）. The sensitivity of “irregular shape” for diagnosing breast cancer was 89.9%, while the sensitivities of other sonographic features ranged from 7.6% to 42.4%. The diagnostic specificities were high for “angular margin”, “microlobular”, “spiculation” and “abundant flow”(89.0％-95.6％). The common sonographic findings of benign lesions included “irregular shape”(66.7%), “obscure margin”(35.1%), “shadowing”(27.2%), and “taller-than-wider” (26.3%). Conclusions“Irregular shape” is the most sensitive sonographic feature in the diagnosis of malignant BI-RADS category 4 and 5 non-palpable breast lesions. Ultrasound can accurately identify the invasive margin features of breast cancers, which is especially useful for the diagnosis of BI-RADS category 5 lesions.

Key words: non-palpable breast lesions, Breast Imaging Reporting and Data System, ultrasound