To conduct a systematic review and meta-analysis to evaluate the effectiveness of Shear Wave Elastography (SWE) combined with Ultrasound (US), for the differential diagnosis of breast lesions. METHODS:  

The literature searches were conducted using KoreaMed, Ovid-MEDLINE, Ovid-EMBASE, and Cochrane Library on December 28, 2015. The studies that were excluded: animal experiments, preclinical experiments, abstracts, reviews, articles not published in Korean or in English, grey literature, case studies, and not breast tumors.

Two authors independently selected articles and evaluated the articles quality using Scottish Intercollegiate Guidelines Network (SIGN). The assessment was based on the following factors: biopsy reduction rate (change in the level of Breast Imaging Reporting and Data System, BI-RADS), and diagnostic performance. RESULTS:  

A total of 23 articles were included in the final assessment. The diagnostic cut-off value of the SWE varied: E_max (16 articles, cut-off 30~108.5 kPa), E_mean (1 article, cut-off 41.6 kPa), qualitative index (5 articles), and qualitative and quantitative index (3 articles).

In the 8 articles, when adding SWE to US, the level of BI-RADS changed from IV to III in 12.8~89% of cases with 0~3.8% false negative rate, and 27.1~73.7% rate of decrease in biopsy for patients who received US.

Meta-analysis was performed on 21 articles (4,558 breast masses). The diagnostic performance of SWE + US vs. US were: pooled sensitivity was 0.94 (95% confidence interval [CI] 0.93~0.95, I=79.0%) vs. 0.94 (95% CI 0.92~0.95, I=83.3%), pooled specificity was 0.75 (95% CI 0.73~0.76, I=96.4%) vs. 0.55 (95% CI 0.53~0.57, I=98.6%). CONCLUSIONS:  

SWE is an effective test for discriminating benign and malignant tumors in patients suspected of breast cancer, which prevents unnecessary biopsy when used alongside the breast US.