US-Guided Radiofrequency Ablation for Low-Risk Papillary Thyroid Microcarcinoma: Efficacy and Safety in a Large Population

• Published in: Korean journal of radiology Vol. 20; no. 12; pp. 1653 - 1661
• Main Authors: Lim, Hyun Kyung, Cho, Se Jin, Baek, Jung Hwan, Lee, Kang Dae, Son, Chang Woo, Son, Jung Min, Baek, Seon Mi
• Format: Journal Article
• Language: English
• Published: Korea (South) The Korean Society of Radiology 01-12-2019; 대한영상의학회
• Subjects: Ablation; Biopsy; Electrodes; Laboratories; Local anesthesia; Metastasis; Patients; Surgery; Thyroid; Thyroid cancer; Tumors; Ultrasonic imaging; 방사선과학; United States > US; Radiofrequency ablation; Papillary thyroid microcarcinoma; Ultrasonography
• ISSN: 1229-6929; 2005-8330
• DOI: 10.3348/kjr.2019.0192

To evaluate the efficacy and safety of radiofrequency ablation (RFA) for low-risk papillary thyroid microcarcinoma (PTMC) in a large population.
Cases of 152 biopsy-proven PTMCs from 133 patients who had undergone RFA for PTMC between May 2008 and January 2017 were included in this study. All patients were either of high surgical risk or refused to undergo surgery. They were followed up for at least 6 months after initial RFA. Ultrasonography (US) and computed tomography were performed to evaluate the PTMC and the presence of neck metastasis before treatment. RFA was conducted using an internally cooled thyroid-dedicated electrode system. Follow-up US was performed at 1 week, and 2, 6, and 12 months, after the initial RFA, and then at every 6-12 months. We evaluated serial changes of ablated tumors, newly developed cancers, lymph node (LN) or distant metastasis and complications.
Complete disappearance was found in 91.4% (139/152) of ablated tumors. Among the 13 tumors in patients who did not show complete disappearance, no tumor displayed any regrowth of the residual ablated lesion during the follow-up period. The mean follow-up period was 39 months. During the follow-up period, there were no local recurrence, no LN or distant metastasis, and no newly developed thyroid cancers. No patients were referred to surgery. The overall complication rate was 3% (4/133) of patients, including one voice change. There were no life-threatening complications or procedure-related deaths.
Our results suggest that RFA is an effective and safe option for treating low-risk PTMC patients who are of high surgical risk or refuse surgery.