Managing TBSRTC III thyroid nodules: evaluating repeat FNA, molecular testing, and surgery.

Area of Science:

• Endocrinology
• Oncology
• Diagnostic Cytopathology

Background:

• Thyroid nodules are common, with most being benign.
• Atypia of undetermined significance (AUS) or Bethesda III nodules present management challenges.
• Current options include surveillance, repeat FNA, molecular testing, and surgery, with molecular testing being costly.

Purpose of the Study:

• To assess the feasibility and cost-effectiveness of repeat FNA for AUS nodules.
• To compare repeat FNA outcomes with molecular testing and surgical intervention.
• To evaluate the utility of prebiopsy ultrasonography in risk stratification.

Main Methods:

• Retrospective multi-institutional study of 131 AUS nodules from 5 hospitals (2018-2024).
• Nodules stratified by initial management: repeat FNA, molecular testing, or surgery.
• Analysis of clinical, ultrasonography findings, malignancy rates, and estimated costs (Medicare rates).

Main Results:

• Repeat FNA yielded a benign diagnosis in 48.7% and AUS in 35.9% of cases.
• Repeat FNA was the most cost-effective management strategy.
• No significant difference in malignancy or surgical intervention rates between repeat FNA and molecular testing.
• Echogenic foci were the only ultrasonography finding significantly associated with malignancy.

Conclusions:

• Repeat FNA is a cost-effective initial approach for AUS nodules, resolving approximately 50% of cases.
• Outcomes regarding malignancy and surgical intervention are comparable to molecular testing.
• Prebiopsy ultrasonography has limited value in predicting malignancy risk for AUS nodules.