Does elastography reduce the need for thyroid FNAs?

Area of Science:

• Radiology
• Oncology
• Pathology

Background:

• Thyroid nodules are common, and accurate characterization is crucial for appropriate management.
• Ultrasound elastography (USE) is an emerging technique to assess tissue stiffness, potentially aiding in thyroid nodule evaluation.
• Ultrasound-guided fine needle aspiration cytology (USgFNAC) is a standard diagnostic tool, but carries risks and costs.

Purpose of the Study:

• To evaluate the diagnostic accuracy of ultrasound elastography (USE) for thyroid nodules.
• To determine if USE can reliably identify benign thyroid nodules.
• To assess the potential of USE to reduce the number of USgFNAC procedures.

Main Methods:

• A prospective study involving 147 thyroid nodules in 146 patients over three years.
• Nodules were initially characterized by B-mode ultrasound.
• Ultrasound elastography (USE) was performed by an experienced operator prior to USgFNAC, with elastographic appearance categorized as soft, intermediate, or hard.

Main Results:

• The study included 122 non-neoplastic, 5 benign neoplasms, 10 indeterminate cytology, and 10 malignant neoplasms.
• Ultrasound elastography (USE) demonstrated a sensitivity of 90.0% and specificity of 79.6% for malignancy.
• The negative predictive value (NPV) was high at 99.1%, indicating a low likelihood of malignancy in USE-negative nodules.

Conclusions:

• Soft thyroid nodules assessed by USE are highly likely to be non-neoplastic.
• Subjective USE assessment by an experienced operator can help avoid unnecessary USgFNAC for benign nodules.
• Intermediate or hard nodules identified by USE should undergo USgFNAC for definitive diagnosis.