Sonoelastography of breast lesions: a prospective study of 215 cases with histopathological correlation.

BACKGROUND Elastography is an imaging technique, which displays the hardness of soft tissue, by showing the behavior of tissue when subjected to mechanical stress. The purpose of this study was to assess the role of ultrasound elastography in differential diagnosis of breast lesions. MATERIALS AND METHODS A prospective study was conducted in our Research Centre, University of Medicine and Pharmacy of Craiova. We introduced in this prospective study 215 patients diagnosed with breast lesions between January 2009 and January 2011. The patients were examined in the supine position and a ductal exploration was made over the breast. The final diagnose was cytology (FNA - fine needle aspiration), histology after excision or follow-up for six months. For obtaining the elastography images, we used a EUS Hitachi EUB 8500 and Siemens ultrasound systems with elastography modules incorporated. For assessment of ultrasound elastography role in differential diagnosis of breast lesions, we performed ROC analysis. RESULTS The elasticity score for benign lesions was on average 1.95±1.1, and for malignant lesions was 4.21±0.9. The mean diameter of malignant lesions was 27.3 mm, which was higher than the average diameter of benign lesions (19.9 mm). The most common histology of the benign nodules was fibroadenomas, cysts, and fibrocystic change. Of the malignant nodules, the most common lesion was infiltrative ductal carcinoma. We obtained a sensitivity of 85.3%, and a specificity of 90% (area under the ROC curve=0.908, 95%CI=0.856-0.945 and p=0.0001) when a cut-off point of 3 was used. CONCLUSIONS Elastography is a method which can complement conventional ultrasound by improving the diagnostic performance. The introduction of ductal ultrasound combined with elastography increased the sensitivity and specificity, the radial technique allowing the precise localization of lesions regarding the breast gland.