Using Real-time Tissue Elastography for Breast Lesion Evaluation

Abstract

The purpose of this study was to prospectively assess the performance of real-time tissue elastography (RTE) in the evaluation of breast masses and correlate RTE and American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) assessments with pathologic findings. Informed consent was obtained from all patients for this Health Insurance Portability and Accountability Act-compliant, Institutional Review Board-approved study. Patients with sonographically visible breast lesions for which a biopsy was recommended were considered potential study participants. Between October 2006 and February 2008, 186 consecutive women with 200 lesions were enrolled. Twelve lesions in 11 patients were excluded, resulting in a study population of 188 lesions in 175 women. After routine B-mode sonographic examination, RTE was performed using a manual free-hand compression technique. Study lesions were assigned elasticity scores (ES) based on the system proposed by Itoh et al (Radiology 2006; 239:341-350), where 1 is normal and 5 represents abnormal strain. The lesion size on RTE and B-mode imaging was compared. Results were correlated with BI-RADS assessment and pathologic findings. Pathologic examination revealed 61 of 188 malignancies (32.4%) and 127 of 188 benign lesions (67.6%). Of the malignant lesions, 84% had ES of 5 and 4, whereas 76% of benign lesions had ES of 1 and 2. The sensitivity of RTE was 92.7%, and specificity was 85.8%, with 4 false-negative and 16 false-positive results. Of the biopsy-proven benign BI-RADS 4A lesions, 63 of 76 (82.9%) had ES of 1 and 2, consistent with normal tissue. Real-time tissue elastography may provide additional characterization of breast lesions, improving specificity, particularly for low-suspicion lesions.