Comparison of Virtual Touch Tissue Quantification and Virtual Touch Tissue Imaging Quantification for diagnosis of solid breast tumors of different sizes.

Abstract

Acoustic radiation force impulse imaging (ARFI) with Virtual Touch Tissue Quantification (VTQ) or Virtual Touch Tissue Imaging Quantification (VTIQ) measures shear wave velocity (SWV), which is proportional to tissue stiffness, a diagnostic parameter for malignancy. To compare the performance of VTQ and VTIQ in diagnosing solid breast tumors. Conventional ultrasound, VTQ and VTIQ were used to examine 246 solid breast tumors from 230 patients. Tumors were grouped according to size: <10 mm, 10-20 mm, >20 mm. Pathological diagnoses were via histological examination of biopsies. ROC curves were used to assess diagnostic performance and optimal cut-off points for VTQ and VTIQ. For all sizes, SWVVTQ and SWVVTIQ were higher for malignant versus benign tumors (P < 0.05). SWVVTQ and SWVVTIQ were both higher for tumors≥10 mm (P < 0.05). Areas under the ROC curves (diagnostic performance index; 0.860-0.952) did not differ significantly between VTQ and VTIQ. Optimal cut-off values for SWVVTQ and SWVVTIQ were higher for tumors≥10 mm. The diagnostic performance of VTQ and VTIQ was moderate to good for solid breast tumors. Although both methods have higher sensitivities in tumors≥10 mm, their overall diagnostic performance was similar for all sizes.