Outcomes of Radiofrequency Ablation Therapy for Large Benign Thyroid Nodules: A Mayo Clinic Case Series

To assess the effectiveness, tolerability, and complications of radiofrequency ablation (RFA) in patients with benign large thyroid nodules (TNs).

This is a retrospective review of 14 patients with predominantly solid TNs treated with RFA at Mayo Clinic in Rochester, Minnesota, from December 1, 2013, through October 30, 2016. All the patients declined surgery or were poor surgical candidates. The TNs were benign on fine-needle aspiration, enlarging or causing compressive symptoms, and 3 cm or larger in largest diameter. We evaluated TN volume, compressive symptoms, cosmetic concerns, and thyroid function.

Median TN volume reduction induced by RFA was 44.6% (interquartile range [IQR], 42.1%-59.3%), from 24.2 mL (IQR, 17.7-42.5 mL) to 14.4 mL (IQR, 7.1-19.2 mL) (P<.001). Median follow-up was 8.6 months (IQR, 3.9-13.9 months). Maximum results were achieved by 6 months. Radiofrequency ablation did not affect thyroid function. In 1 patient with subclinical hyperthyroidism due to toxic adenoma, thyroid function normalized 4 months after ablation of the toxic nodule. Compressive symptoms resolved in 8 of 12 patients (67%) and improved in the other 4 (33%). Cosmetic concerns improved in all 8 patients. The procedure had no sustained complications.

In this population, RFA of benign large TNs performed similarly to the reports from Europe and Asia. It induces a substantial volume reduction of predominantly solid TNs, improves compressive symptoms and cosmetic concerns, and does not affect normal thyroid function. Radiofrequency ablation has an acceptable safety profile and should be considered as a low-risk alternative to conventional treatment of symptomatic benign TNs.