Value of Virtual Touch Tissue Imaging Quantification for Evaluation of Ultrasound Breast Imaging-Reporting and Data System Category 4 Lesions

The purpose of the study was to evaluate the value of 2-D shear wave elastography (SWE) of virtual touch tissue imaging quantification (VTIQ) for ultrasound (US) Breast Imaging-Reporting and Data System (BI-RADS) category 4 lesions. One hundred sixteen lesions were subject to conventional US, conventional strain elastography (SE) of elasticity imaging (EI), acoustic radiation force impulse (ARFI)-induced SE of virtual touch tissue imaging (VTI) and VTIQ before biopsies. Of the 116 lesions, 69 (59.5%) were benign and 47 (40.5%) were malignant. Significant differences were found between benign and malignant lesions in EI score, VTI score and shear wave speed (SWS) on VTIQ (both p < 0.05). The cut-off values were EI score ≥4, VTI score ≥4 and SWS ≥3.49 m/s, respectively. The diagnostic performance of VTIQ in terms of area under receiver operating characteristic curve (AUROC) were the highest (i.e., AUROC = 0.907), in comparison with EI, VTI alone or a combination of both. The associated sensitivity, specificity and accuracy were 87.2%, 82.6% and 84.5%, respectively. The combination of VTI and VTIQ, however, was similar with US BI-RADS (p = 0.475) in sensitivity in that only two (4.3%) of 47 malignant lesions were misdiagnosed as benign that were BI-RADS category 4b on US. VTIQ is valuable to differentiate benign from malignant BI-RADS category 4 lesions, and the combination of VTI and VTIQ might be useful for patient selection before biopsy.