Multimodal ultrasound: a non-invasive method for identifying dedifferentiation of papillary thyroid carcinoma during active surveillance.

Objectives: To assess the diagnostic accuracy of multimodal ultrasound in differentiating anaplastic thyroid carcinoma (ATC) from papillary thyroid carcinoma (PTC) and to evaluate its capability in detecting thyroid carcinoma (TC) aggressiveness.

Methods: Sixty nude mice were randomly assigned to ATC and PTC groups and injected subcutaneously with KHM-5M and TPC-1 cell lines, respectively. Tumors were analyzed using B-mode ultrasound (B-US), Color Doppler flow imaging (CDFI), elastography, and contrast-enhanced ultrasound (CEUS).