Radiofrequency Ablation of Cervical Thyroid Cancer Metastases-Experience of Endocrinology Practices in the United States.

Context: Radiofrequency ablation (RFA) is used in the United States to treat benign thyroid nodules; however, experience with treating cervical recurrence/persistence of papillary thyroid cancer (PTC) is limited. Objective: To evaluate the efficacy RFA for the treatment of cervical recurrence/persistence of PTC in the United States. Methods: This is a retrospective, multicenter study of 8 patients who underwent RFA of 11 cervical metastatic PTC lesions between July 2020 and December 2021. The volume reduction (VR) of the lesions, thyroglobulin (Tg) levels and complications following RFA were assessed. Energy applied per unit volume (E/V) during RFA was also determined. Results: Nine out of 11 (81.8%) lesions had initial volume under 0.5 mL and showed a complete (n = 8) or near-complete (n = 1) response. The 2 lesions with initial volume over 1.1 mL had a partial response, 1 of which had regrowth. There was a median VR of 100% (range 56.3-100%) after a median follow-up period of 453 days (range 162-570 days), with corresponding decline in Tg levels from a median of 0.7 ng/mL (range 0-15.2 ng/mL) to a median of 0.3 ng/mL (range 0-1.3 ng/mL). All patients with an E/V of at least 4483 J/mL or higher had a complete or near-complete response. There were no complications. Conclusion: RFA performed in an endocrinology practice is an efficacious treatment option for selected patients with cervical metastases of PTC, particularly those who cannot or do not want to undergo further surgery.