Trends in thyroid function following radiofrequency ablation of benign, nonfunctioning thyroid nodules: A single institution review.

Background: Radiofrequency ablation (RFA) effectively reduces volume and improves symptoms of benign, non-functioning thyroid nodules (NFTNs). Given RFA's unclear impact on thyroid function, we examined post-RFA trends in thyroid hormones and antibodies.

Methods: A retrospective cross-sectional analysis was conducted of patients treated at Columbia University with RFA for benign NFTNs between August 2019 and July 2023. Thyroid function tests were recorded pre-RFA and repeated 3, 6, and 12 months post-RFA.

Results: We analyzed 185 patients with 243 benign NFTNs who underwent RFA. Volume reduction ratio increased post-RFA. Mean TSH increased to 2.4 mlU/L (p ​= ​0.005) at 3 months post-RFA and decreased to 1.8 mlU/L (p ​= ​0.551) by 12 months post-RFA. Tg and TPO antibody levels peaked at 6 months post-RFA (103.1 IU/mL, p ​= ​0.868 and 66.6 IU/mL, p ​= ​0.523, respectively).

Conclusions: With expected volume reduction post-RFA, we observed transient relative hypothyroidism as well as transient increases in thyroid antibodies, with normalization of these changes within 12 months.