Cooled microwave ablation of thyroid nodules: Initial experience

Objective: To evaluate if internally cooled microwave ablation (cMWA) is a safe and effective method for treatment of benign and malign thyroid nodules. Methods: 9 patients with 11 symptomatic cold benign thyroid nodules and 1 recurrent thyroid carcinoma ranging in volume from 9.1 to 197 ml (mean size 52 +/- 57 ml) were treated with cMWA. The mean age of the patients was 59 years. Pain during the treatment was measured on a 10-point scale. Side effects revealed by ultrasound or patients' complaints were documented. Periablative efficacy was measured 24 h after cMWA as change (A) in serum thyreoglobulin (Tg). Nodule elasticity was measured on a 4-point scale, blood circulation and echogenicity on a 3-point scale. Results: All patients tolerated cMWA well. Median pain intensity averaged 2.1 +/- 0.8 (range: 1-3). Postablative hematoma was observed in all cases. In no cases ablation led to hoarseness, superficial burns, nodule ruptures, vagal reactions or dysphagia. cMWA lead to a significant decrease of blood circulation, nodule echogenicity and a significant increase of elasticity (A = 1.1 +/- 0.33; 0.8 +/- 0.4 and 1.1 +/- 0.6 points)(p < 0.05). An average increase of 4495 ng/ml Tg was measured (p < 0.05). Conclusions: cMWA is an effective and secure method for treatment of thyroid nodules. (C) 2016 Elsevier Ireland Ltd. All rights reserved.