A recent study of 215 patients who received RFA for thyroid nodules and were followed for 5 years was recently published in the Journal of Clinical Endocrinology and Metabolism.
All patients with a confirmed diagnosis of a benign thyroid nodule received 1 treatment of RFA. The study showed that majority of the nodules had up to 80% reduction within the first year of treatment.
9 patients (4.1%) had regrowth of the nodule in the first year of treatment, but these nodules were found to be benign on repeat biopsy.
A link to the published study is provided here, https://www.ncbi.nlm.nih.gov/pubmed/30860579