MON-462 - Single-Session Trans-Isthmic Radiofrequency Ablation (RFA) for Benign Thyroid Nodules: A 24-Month Single-Practice Experience

Background: Radiofrequency ablation (RFA) is a globally established, minimally invasive therapy for benign thyroid nodules, first introduced in Asia in 2002. Despite its international standard-of-care status for preserving thyroid function and avoiding surgery, its adoption in the United States remains in an early phase, confined primarily to specialized centers. This study evaluates the clinical efficacy and safety of office-based RFA within a U.S. practice cohort, contributing to the growing body of domestic evidence at a pivotal moment for the technique's integration.

Methods: This study is a retrospective, single-center review of 118 consecutive patients (96 female, 22 male; mean age 60 ± 11.3 years) with cytologically confirmed benign nodules (Bethesda II) treated with ultrasound-guided radiofrequency ablation (RFA), between 2023 and 2025. All treatments were performed in an office-based setting by a board-certified endocrinologist utilizing the trans-isthmic moving-shot technique with a bipolar, water-cooled-probe system.
The primary study endpoint was the volume reduction ratio (VRR) assessed at six months post-procedure, with a VRR ≥50% constituting a favorable therapeutic response. A secondary endpoint was patient-reported control of compressive symptoms, including dysphagia, globus sensation, and voice changes.

Results: The mean baseline nodule volume was 21.4 mL, decreasing to 4.8 mL at 6 months, yielding a mean VRR of 75 ± 13.5%. A favorable response (VRR ≥50%) was achieved in 86% of patients (101/118), with 28% (33/118) experiencing volume reductions of ≥85%. Assessment of the secondary endpoint showed that pre-procedure compressive symptoms were completely resolved in 60% of patients (71/118) and significantly improved in nearly all others. The procedure was very well tolerated by all patients and no major complications occurred. Minor complications, including transient voice changes, local bruising, swelling, and pain, were mild, self-limited, and did not require intervention. All patient were euthyroid pre-procedure, and remained euthyroid post-procedure. A strong positive correlation existed between initial volume and VRR (r = 0.77, p < 0.001).

Conclusions: Office-based, single-session RFA is a highly effective and safe treatment for benign thyroid nodules, achieving substantial volume reduction and significant symptom relief. These results support its role as a primary treatment strategy and provide timely U.S. data to inform and accelerate the broader domestic adoption of this gland-preserving therapy.