Diagnostic Accuracy of Shear-Wave Elastography for Breast Lesion Characterization in Women: A Systematic Review and Meta-Analysis

The aim of this study was to assess the diagnostic accuracy of 2-D shear-wave elastography (SWE) for differentiating benign and malignant breast lesions in women with abnormal findings on mammography.Included in this review are studies of diagnostic accuracy published before June 2021 using 2-D SWE to evaluate female breast lesions. Included studies were required to include at least 50 lesions, report quantitative shear-wave speed (SWS) thresholds, and include a reference standard of either biopsy or 2-year stability. Included studies used the mean, maximum, minimum, or SD of SWS for classification. A systematic search of PubMed, Scopus, Embase, Ovid-MEDLINE, the Cochrane Library, and Web of Science was performed. Bias and applicability of the studies were assessed using Quality Assessment of Diagnostic Accuracy Studies 2. A hierarchical summary receiver operating characteristic model was used to arrive at the summary statistics.Eighty-seven prospective and retrospective studies were included, encompassing 17,810 women (mean age 42.3 ± 10.4 years) with 19,043 lesions (7,623 malignant). Summary sensitivities and specificities, respectively, were 0.86 (95% confidence interval [CI], 0.83-0.88) and 0.87 (95% CI, 0.84-0.88) for mean SWS, 0.83 (95% CI, 0.80-0.85) and 0.88 (95% CI, 0.86-0.90) for the maximum, 0.86 (95% CI, 0.74-0.93) and 0.81 (95% CI, 0.69-0.89) for the minimum, and 0.82 (95% CI, 0.77-0.86) and 0.88 (95% CI, 0.85-0.91) for the SD. Alternatively, the areas under the receiver operating characteristic curve were 0.93 (95% CI, 0.91-0.94), 0.92 (95% CI, 0.90-0.94), 0.90 (95% CI, 0.82-0.96), and 0.92 (95% CI, 0.88-0.94), respectively.This review demonstrates the discriminative power of SWE in the diagnosis of breast cancer. Using the resulting likelihood ratios, SWE may prove beneficial in downgrading BI-RADS® 4a or upgrading BI-RADS 3 lesions. However, current society guidelines do not provide definitive recommendations regarding the use of SWE and its counterpart strain elastography (SE). Comparison with our results suggests that SE alone or a combination of SE and SWE may provide better diagnostic performance than SWE alone and serve as an adjunct to current diagnostic techniques.