Does Radiofrequency Ablation Induce Neoplastic Changes in Benign Thyroid Nodules: A Preliminary Study

Background: To evaluate the clinical feasibility of radiofrequency ablation (RFA) of benign thyroid nodules along with cytomorphological alteration, and any malignant transformation through biopsy. Methods: The data were retrospectively collected between April 2008 and June 2013 and core needle biopsy (CNB) was performed on 16 benign thyroid nodules previously treated using RFA. The parameters of the patients were compared, between the time of enrollment and the last follow-up examination, using linear mixed model statistical analysis. Results: No atypical cells or neoplastic transformation were detected in the undertreated peripheral portion of treated benign nodules on the CNB specimen. RFA altered neither the thyroid capsule nor the thyroid tissue adjacent to the treated area. On histopathological examinations, we observed 81.2% acellular hyalinization, which was the most common finding. After a mean follow-up period of over 5 years, the mean volume of thyroid nodule had decreased to 6.4 +/- 4.2 mL, with a reduction rate of 81.3%+/- 5.8% (P<0.0001). Conclusion: RFA is a technically feasible treatment method for benign thyroid nodules, with no carcinogenic effect or tissue damage of the normal thyroid tissue adjacent to the RFA-treated zone.