The effectiveness and safety of thermal ablation for thyroid carcinoma lymph node metastasis are affected by the diameter of metastatic lymph nodes: A meta-analysis.

[BACKGROUND] To explore the diameter of lymph nodes with metastatic thyroid carcinoma and the effectiveness and safety of thermal ablation.

[METHODS] Several databases were searched for literature on the treatment of thyroid carcinoma metastatic lymph nodes by thermal ablation. A subgroup analysis was performed according to the diameter of the metastatic lymph nodes. The measures included pooled estimates of mean volume reduction, pooled proportions of total disappearance and recurrence, and the pooled proportions of overall complications.

[RESULTS] There were 20 studies with 372 patients and 620 metastatic lymph nodes included. Based on the average maximum diameter of the metastatic lymph nodes, they were divided into three groups: A (≤ 10 mm), B (10 < diameter ≤ 20 mm), and C (> 20 mm). The study results indicated a significant decrease in the average volume only in groups A and B. The ratio of tumor disappearance showed that group A had the highest percentage, followed by group B and then group C. The recurrence rates were comparable between groups A and B, but slightly lower than in group C. Moreover, the overall complication rates for the three groups were ranked as follows: group A > group C > group B.

[CONCLUSION] Overall, thermal ablation is an effective and safe treatment for thyroid cancer metastatic lymph nodes with diameters of 10-20mm.