Clinical trial of thyroid RFA for papillary microcarcinomas
N. Fukunari, M. Nakano & K. Arai
The management of papillary thyroid microcarcinomas (PTMC) has been controversial and only observation without surgery has been advocated for the low-risk PTMC. Radio-frequency ablation(RFA)has been applied to thyroid nodule, which shows safe and useful results for benign thyroid nodules. In our institution, not only benign nodules, but thyroid malignancies have been attempted to be therapeutic objectives by RFA. The aim of this study is to evaluate the efficacy of RFA for primary PTMC.
Objectives: Eighty-nine cases were treated by RFA from 2007 in our institution, which consisted of 55 hyperplastic nodules, 9 AFTNs, 5 local recurrences of papillary carcinomas, 11 metastatic LNs and 9 primary PMTCs. All of 9 patients with PTMC were initial cases without the history of previous thyroid surgery or irradiation, and refused the surgery because of cosmetic and private reasons.
Methods: RFA has carried out under general or local anesthesia and under careful US imaging guidance. The equipment of 1718G needle electrodes were applied to thyroid RFA: STARmed RF electrode (STARmed, Korea) As an intra-operative assessment for the estimation of extent of ablated area, gray-scale US, color-Doppler imaging, Elastography and contrast enhanced US were applied to judge the satisfactory ablation.
Results: All cases showed no side effect or thermal damage, and discharged after one night observation. The efficacy of RFA has been verified with both imaging diagnosis and repeated FNA. Post therapeutic FNA revealed no cancer cells remained in 8 of 9 PTMC cases.
Conclusions: The efficacy of RFA has shown satisfactory results and a possibility to be one of alternative treatments for PMTC. Long-time follow-up and careful attention for thermal damage to surrounding tissues are required.
Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.