ObjectiveTo investigate the value of contrastenhanced ultrasonography in differential diagnosis between benign and malignant breast mass. MethodsTotally 65 patients with 70 breast masses were evaluated by general ultrasonography and contrastenhanced ultrasonography with contrast agent SonoVue. The related indexes, such as the degree and mode of contrast enhancement, the lesion boundaries and dissipation mode, were used to describe the difference between benign and malignant mass, which was also compared with pathological results. ResultsHistopathological examination revealed that benign mass was in 37 cases and malignant in 28 cases. The sensitivity, accuracy, positive predictive value, and negative predictive value of contrastenhanced ultrasonography with contrast agent SonoVue were significantly higher than that of general ultrasonography (Plt;0.05), while no significant difference in diagnostic specificity and misdiagnosis rate was observed between them (Pgt;0.05). All tumors showed contrast enhancement in various degrees. Of 28 patients with enhanced mass, hyperenhancement in 22 cases and nodular inhomogeneous enhancement in 21 cases were observed and the boundaries of malignant tumor were irregular with ill-defined and radial enhancement. Most of benign tumors were represented by weak, homogeneous enhancement, and the shape was regular with smooth and tidy boundary and intact capsule except seven cases with unclear boundary. These imaging characteristics of benign and malignant tumors were obviously different (P=0.000). In the resolution phase, both benign and malignant mass showed heterogeneous or homogeneous dissipation, which was not significantly different (P=0.791). ConclusionCompared with general ultrasonography, contrast enhanced ultrasonography may be more helpful for the differential diagnosis of benign and malignant breast tumors.