Enhancement Patterns and Parameters of Breast Cancers at Contrast-enhanced US: Correlation with Prognostic Factors

Abstract

To investigate the correlation between enhancement patterns and parameters of contrast material-enhanced ultrasonography (US) with prognostic factors in breast cancers. The study was approved by the institutional ethics committee, and written informed consent was obtained. Surgical resection specimens of 74 malignant breast lesions in 74 women (mean age, 55 years; age range, 32-78 years) who had undergone contrast-enhanced US were included. Different contrast enhancement patterns (enhancement degree, order, and margin; internal homogeneity; perfusion defect; and radial or penetrating vessels) and parameters (wash-in time, peak intensity, time to peak, area under the time-intensity curve, ascending slope, and descending slope) were evaluated. Pathologic prognostic factors, including histologic grade, lymph node status, tumor diameter, microvessel density (MVD), estrogen and progesterone receptor status, and c-erb-B2, p53, and Ki-67 expression were determined. Correlation of enhancement patterns and parameters with prognostic factors was analyzed with the Pearson χ2 test, Spearman rank correlation test, and logistic regression analysis. Some enhancement features were associated, albeit not significantly, with prognostic factors. Perfusion defect was the most accurate enhancement criterion for higher histologic grade (grade III) (P=.016), negative estrogen receptor expression (P=.006), positive c-erb-B2 expression (P=.013), larger tumor diameter (≥2 cm) (P=.016), and increased MVD (P=.019). Radial or penetrating vessels were associated with lymph node status (P=.010). Hyperenhancement may be useful in reflecting increased MVD (P=.008) and positive p53 expression (P=.037). For contrast enhancement parameters, ascending slope was the best discrimination criterion for proliferative activity (P=.003). Enhancement patterns and parameters of contrast-enhanced US may be useful in the noninvasive prediction of prognostic factors of breast cancers.