Thermal Ablation for Small Papillary Thyroid Cancer: A Systematic Review

Background: Although clinical studies indicate that thermal ablation is effective in treating low-risk papillary thyroid microcarcinomas (PTMCs), the effectiveness of this treatment in patients with low-risk PTMC has not yet been systematically evaluated. Methods: Ovid-MEDLINE and EMBASE databases were searched for studies published through May 1, 2019, which report the efficacy of thermal ablation in patients with low-risk PTMCs. Data were extracted and methodological quality was assessed independently by two radiologists according to PRISMA guidelines. Results: This systematic review identified 503 low-risk PTMCs in 470 patients treated by thermal ablation from 9 studies. During follow-up, no patient experienced local tumor recurrence or distant metastasis, whereas two patients (0.4%) experienced lymph node (LN) metastasis. One patient (0.2%) developed a new PTMC, which was successfully treated by additional ablation. Five patients (1.1%) underwent delayed surgery after ablation, including the two patients with LN metastasis and three additional patients with unknown etiology. Conclusions: Thermal ablation is an excellent local tumor control method in patients with low-risk PTMCs. Strict inclusion criteria and technical expertise are required to obtain favorable results.