A comparative study of 2D and 3D ultrasonography for evaluation of solid breast masses

Objective: To compare image quality and diagnostic accuracy of 2D with 3D ultrasonography in solid breast masses. Methods and material: To rate image quality, two radiologists compared lesion contrast and characterization of 507 solid breast masses in 2D and 3D ultrasonography and then graded the 3D imaging in 3-point scale. To characterize the masses, the same radiologists rated the examination for clarity of margin, posterior acoustic feature, and clustered microcalcifications within a mass. In addition, the masses were assigned BI-RADS® categories as proposed by the American College of Radiology, criteria using just ultrasonographic features. In the 202 pathologically confirmed cases, sensitivity, specificity, positive predictive value, negative predictive value, and false negative rate for diagnosis of breast cancer in 2D and 3D ultrasonography were assessed. Image quality and diagnostic accuracy were further evaluated according to the size of the masses. Results: Two observers rated 3D imaging superior to 2D imaging in terms of lesion contrast and characterization of the masses. Especially, superiority of 3D ultrasonography in terms of image quality was increasing in more than 10 mm sized masses. However, diagnostic accuracy including sensitivity, specificity, positive predictive value, negative predictive value, and false negative rate for diagnosis of breast cancer of 3D imaging was not different from 2D imaging. Conclusion: In spite of superior image quality on 3D ultrasonography, it does not provide additional benefits to diagnostic accuracy for diagnosis of breast cancer.