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

BACKGROUND: 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.

OBJECTIVE: To compare the performance of VTQ and VTIQ in diagnosing solid breast tumors.

METHODS: 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.

RESULTS: 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.

CONCLUSION: 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.