Multimodal Ultrasound for Evaluating Gross Extrathyroidal Extension in Papillary Thyroid Cancer: A Comparative Study

Area of Science:

• Radiology and Imaging
• Oncology
• Medical Diagnostics

Background:

• Papillary thyroid cancer (PTC) diagnosis requires accurate assessment of gross extrathyroidal extension (gETE).
• Multimodal ultrasound offers potential for improved gETE evaluation.

Purpose of the Study:

• To compare the diagnostic performance of B-mode ultrasound (BMUS), contrast-enhanced ultrasound (CEUS), and strain elastography (SE) for gETE in PTC.
• To evaluate the utility of combined ultrasound modalities for gETE assessment.

Main Methods:

• Retrospective review of preoperative imaging features from 245 PTC patients (277 nodules).
• Analysis of BMUS, CEUS, and SE features for gETE diagnosis.
• Comparison of diagnostic accuracy and consistency using statistical tests and ROC analysis.

Main Results:

• SE showed higher diagnostic accuracy (93.1%) and consistency (kappa=0.759) for gETE compared to BMUS and CEUS.
• Specific SE features, like strain stiffness color replacement, were highly indicative of gETE.
• Combined ultrasound modalities demonstrated improved diagnostic performance over single modalities.

Conclusions:

• Strain elastography is a superior ultrasound modality for diagnosing gETE in PTC, particularly for strap muscle invasion.
• Combining ultrasound techniques can further enhance diagnostic accuracy for gETE.