Radiofrequency ablation for the treatment of autonomously functioning thyroid nodules.

Background: Some patients with autonomously functioning thyroid nodules (AFTN) are not suitable for surgery or radioiodine therapy. Therefore, minimally invasive alternative treatments, such as ethanol ablation or radiofrequency ablation (RFA), are necessary.

Methods: This study included nine patients (4 toxic and 5 pretoxic patients; male to female ratio = 1:8; mean age, 47 +/- 17 (range, 25-71) years) who were not eligible for surgery or radioiodine therapy. All of the patients showed hot nodule with suppression of normal thyroid gland in (99m)Tc pertechnetate scintigraphy. RFA was performed using a 17- and 18-gauge internally cooled electrode. Nodule volume, thyroid function, scintigraphy, symptom score (visual analogue scale, 0-10 cm), cosmetic grading score (4-point scale), and complications were evaluated before treatment and at 1, 3, and 6 months follow-up.

Results: Mean volume of the index nodule was 14.98 +/- 25.53 (range, 0.29-82.29) mL. After RFA it decreased at 1 month (12.01 +/- 25.97 mL, p = 0.015), 3 months (7.27 +/- 15.13 mL, p = 0.011), 6 months (8.27 +/- 21.29 mL, p = 0.008), and the last month (7.57 +/- 19.99 mL, p = 0.008). Initial mean T3, fT4, and TSH were 156.2 +/- 42.1 ng/dL, 1.73 +/- 0.40 ng/dL, and 0.052 +/- 0.087 mU/mL, respectively. A significant improvement of mean T3, fT4, and TSH were observed at last follow-up (T3: 116.8 +/- 20.7 ng/dL, p = 0.015; fT4: 1.37 +/- 0.26 ng/dL, p = 0.036; TSH: 1.454 +/- 1.756 mU/mL, p = 0.012). After ablation, four patients became a cold or normal scan and five remained as a hot nodule. The mean symptom and cosmetic grading score was reduced from 2.4 +/- 1.7 to 0.6 +/- 0.7 (p = 0.011) and from 3.1 +/- 1.2 to 1.4 +/- 1.0 (p = 0.017), respectively. No major complications were encountered.

Conclusions: RFA seems to be effective and safe for the treatment of AFTN.