Shear wave elastography and Afirma™ gene expression classifier in thyroid nodules with indeterminate cytology: a comparison study
This study compares shear wave elastography (SWE) and Afirma™ gene expression classifier (GEC) for diagnosis of malignancy in thyroid nodules (TNs) with Bethesda Classification (BC) III or IV indeterminate cytology. This preliminary single-center prospective study evaluated 151 consented patients with 151 indeterminate TNs (123 BC III, 28 BC IV) on fine-needle aspiration biopsy (FNAB). B-mode ultrasound, vascularity, and SWE were performed prior to FNAB. TN stiffness was measured as shear wave velocity (SWV) in meters per second (m/s). The stiffest area of the TN was selected for SWV measurement. GEC testing was performed with a second FNAB. Surgery was recommended for GEC-suspicious TNs, or GEC-benign TNs with two or more worrisome B-mode US features. Surgical pathology confirmed 31 malignant TNs. This preliminary study indicates that SWE and GEC are independent predictors of malignancy in TNs with BC III or IV.
