Risk of Malignancy in Solid Breast Nodules According to Their Sonographic Features

Abstract

OBJECTIVE: The purpose of this study was to assess the risk of malignancy for each type of sonographic feature in solid breast nodules. METHODS: The study included 304 patients from the Department of Gynecology and Obstetrics of the Federal University of Goiás who had solid breast nodules. A medical trainee, working under the supervision of a preceptor, obtained the sonographic images of the breast, and the features were recorded in a questionnaire. Each sonographic feature was analyzed and compared with the anatomic and pathologic findings after the lesion was excised. RESULTS: Of the 304 patients included in the study, 292 (96%) had a conclusive diagnosis. Among these women, 216 (74%) had benign tumors and 76 (26%) had malignant tumors. The odds ratio of malignancy in breast nodules, as calculated by multivariate analysis, was as follows: lesions without circumscribed margins, 17.02 (95% confidence interval, 5.28-54.90); lesions with heterogeneous echo texture, 7.70 (2.99-19.84); lesions with thickened Cooper ligaments, 15.61 (1.08-225.10); nodules whose anteroposterior dimension was larger than their width, 3.29 (1.09-9.96); those with an anterior echogenic rim, 2.59 (0.80-8.40); and those with posterior shadowing, 1.57 (0.62-4.01). Among the 133 cases that had all the sonographic features of a benign lesion, 3 nodules (2.3%) had a histologic diagnosis of malignant. CONCLUSIONS: Sonography is a diagnostic method that can help establish the differentiation between benign and malignant solid tumors. A lack of circumscribed margins, heterogeneous echo patterns, thickened Cooper ligaments, and an increased anteroposterior dimension can indicate a higher probability of malignancy in solid breast nodules.