Safety and efficacy of ultrasound-guided percutaneous thermal ablation in treating low-risk papillary thyroid microcarcinoma: A pilot and feasibility study.

ABSTRACT

OBJECTIVE: This study aimed to evaluate the safety and efficacy of thermal ablation in treating low-risk unifocal papillary thyroid microcarcinoma (PTMC). MATERIALS AND METHODS: Patients with unifocal PTMC were enrolled in this study, and thermal ablations were performed. Contrast-enhanced ultrasound was used to estimate the extent of ablation immediately after thermal ablation; complications were recorded. The size and volume of the ablated area and thyroid hormones were measured, and the clinical evaluations were performed at 1, 3, 6, 12, and 18 months after thermal ablation. From July 2016 to July 2017, the prospective study was conducted involving 107 patients. Thermal ablation was well tolerated without serious complications. RESULTS: Compared with the volume immediately after thermal ablation, the mean volume reduction ratio (VRR) of ablated lesions was 0.457 ± 0.218 (range 0.040-0.979), 0.837 ± 0.150 (range 0.259-1), 0.943 ± 0.090 (range 0.491-1), 0.994-0.012 (range 0.938-1), and 0.999 ± 0.002 (range 0.992-1) at 1, 3, 6, 12, and 18 months after thermal ablation, respectively. Significant differences in the VRR were found between every two follow-up visits (P < 0.01). Results of patients' thyroid function test before thermal ablation and at 1 month after thermal ablation were normal, and no significant differences were observed (P > 0.05). No tumor regrowth, local recurrence, or distant metastases were detected during follow-up visits. CONCLUSION: Thermal ablation is a short-term safe and effective method in treating low-risk small PTMCs, which can be considered a potential alternative therapy for patients with PTMC.