Multiple overlapping microwave ablation in benign thyroid nodule: a single-center 24-month study

OBJECTIVE: This study aimed to evaluate the safety and long-term efficacy using the multiple overlapping ablation technique with a novel non-cooled microwave system in benign symptomatic thyroid nodules. METHODS: This prospective cohort single-center study collected complication data from the start of the procedure to 30 days postoperatively and evaluated the safety and effectiveness with a follow-up of 24 months. Ultrasound examinations were performed to determine the volume shrinkage during follow-up. Thyroid function cosmetic and symptoms scores and satisfaction degree were evaluated. RESULTS: A total of 30 symptomatic benign thyroid nodules were treated by microwave ablation using a power between 15 and 30 W depending on the size of the nodule to be treated. The volume reduction rates in months 1, 3, 6, 9, 12, and 24 after ablation were 32, 59, 67, 69, 73, and 81%, respectively. The mean symptom score and mean cosmetic score before treatment were 4 and 3, respectively, while after treatment they dropped to 3 and 1, respectively. Thyroid function indicators fluctuated in the normal range and those with hyperthyroidism recovered to normal parameters. One case of temporary laryngeal paralysis occurred postoperatively and fully recovered in less than 3 months. CONCLUSIONS: The novel microwave ablation system presented herein can help achieve good clinical success rate in benign thyroid nodules with a satisfying safety profile. The microwave ablation performed with the multiple overlapping ablation technique could be a good alternative to surgery and radiofrequency ablation in the management of benign thyroid nodules.