Endocrine Abstracts

Introduction: Thyroid nodules can be detected by ultrasound (US) in 20–30% of unselected populations. Various non-surgical techniques such as laser and radiofrequency ablation have been developed to reduce thyroid nodule size. High-intensity focused ultrasound (HIFU) ablation is a new, non-invasive method that has been shown recently. The aim of our study was to assess the long-term efficacy and safety of US-guided HIFU treatment of benign solid thyroid nodules.

Methods: In our prospective study, 14 patients, mean age 47.6±11.2 years, were treated with US-guided HIFU system (EchoPulse, Theraclion) in one session and under conscious sedation. Thyroid nodule volume and volume reduction were established at baseline, 1, 3, 6, and 12 months after treatment. Adverse events were evaluated and pain related to treatment was rated on 0–100 mm visual analogue scale (VAS). Written informed consent was acquired from all patients.

Results: The mean energy applied per nodule volume was 3.7±1.5 kJ/ml. The mean nodule volume decreased from 4.97±2.54 to 3.56±2.01 ml at 1 month, 2.84±1.95 ml at 3 months, 2.55±2.23 ml at 6 months, and reaching 2.35±2.34 ml at 12 months follow-up. The mean nodule reduction was 29.5±15.9% at 1 month (P<0.001), 46.2±18.5% (P<0.001) at 3 months, and 52.8±23.3% (P<0.001) at 6 months follow-up. By the 12th month, the mean volume reduction was 55.7±27.2% with a maximum of 95.4%. Transient subcutaneous oedema and mild skin redness were observed in two patients. VAS score was 26.1±19.5 mm.

Conclusion: One session HIFU ablation is effective non-invasive treatment for benign thyroid nodules at long-term follow-up, without serious adverse events. Our results indicate that US-guided HIFU might become an alternative to surgery and other minimally invasive treatment techniques.

Disclosure: The device for US-guided HIFU treatment and financial support for the supplies were provided by Theraclion (Paris, France).