Ultrasound-guided treatment of benign partially cystic thyroid nodules: a comparative study between radiofrequency ablation and ethanol ablation

Abstract

Objective To explore the efficacy of radiofrequency ablation (RFA) and ethanol ablation (EA) for treating partially cystic thyroid nodules. Methods One hundred and twenty-four patients with a single partially cystic thyroid nodules which caused pressure symptoms or cosmetic problems were treated with RFA (n=42), EA (n=39) or RFA+ EA(n=43). The inactivation rate of the nodule, tumor volume reduction rate, symptom scores (0-10) and complications were evaluated before and after treatment. Results The mean inactivation rate of RFA, EA and RFA+ EA groups was (87.50±5.77)%, (57.00±6.12)%, (90.03±5.39)%, respectively. The inactivation rate of the nodule was negatively related to the volume of the solid part of the nodule. As to nodules with the volume ranging from 30 to 45 ml, the inactivation rate of RFA group was lower than RFA+ EA group. Nodule volume reduction ratio (percentage) at 12-month follow-up was 90.45% for RFA group, 69.88% for EA group, and 93.28% for RFA+ EA group.Regarding mean volume reduction, there were no difference between RFA+ EA and RFA group (P>0.05), while there were significant differences between RFA+ EA and EA group (P 0.05) on the volume reduction ratio of nodule based on cystic part percentage between RFA group and RFA+ EA group. The rate of the complication was 7.14%, 2.56%, 2.33%, respectively. Conclusions Ultrasound-guided percutaneous aspiration combined with RF ablation yielded better results than EA ablation. But due to ethanol ablation being less expensive and simpler to perform than RFA, ethanol ablation should be the first-line treatment technique for benign thyroid nodules with cystic part percentage more than 50%, while radiofrequency ablation as first-line treatment for benign thyroid nodules with cystic part percentage less than 50%. Key words: Ultrasonography; Thyroid nodule; Ethanol ablation; Radiofrequency ablation