Corresponding to Dr. Shuhang Xu (Endocrine and Diabetes Center, Jiangsu Province Hospital on Integration of Chinese and Western Medicine, Jiangsu Province Academy of Traditional Chinese Medicine, Nanjing University of Chinese Medicine, Nanjing, China) shuhang Xu shuhangxu@vip.163.com
The patient was a 42-year-old female with a suspicious nodule in left lobe on ultrasound. Fine needle aspiration cytology has confirmed the diagnosis as papillary thyroid carcinoma. Preoperative ultrasound and enhanced neck CT showed no signs of lymph node metastasis.
Ultrasound-guided MWA was performed with a MWA system (KY-2000, Canyon Medical, Nanjing, China) consisting of a generator, a power distribution system and an antenna. A cooled shaft antenna with 1.6-mm diameter, 10-cm length and 3-mm distance from the electrode to the needle tip was used to puncture into the thyroid nodule. The MWA system produced 2450 MHz and 35 W output power and the ablation time was 382 seconds.
The mixture of lidocaine and normal saline is continuously injected for hydrodissection to expand the ablation area and prevent the potential damage to adjacent tissues. For complete ablation, we combined the fixed-needle technique with the moving-shot technique to achieve point-by-point ablation of lesions and surrounding tissues. Vaporization is observed around the probe or electrode during the ablation, and the replacement of the transient hyperechoic area by the complete hyperechoic area in the tumor lesions indicates a complete ablation. We intermittently communicated with the patient during the MWA procedure, aiming to reduce the potential damage to the recurrent laryngeal nerve. Patient did not experience intolerable pain or significant discomfort that required treatment suspension during MWA procedures. Contrast-enhanced ultrasound was performed after operation, and there was no contrast agent perfusion in the ablation area. The size of the ablation area was 1.8*1.1*1.7cm.
The patient was not given TSH suppression treatment after ablation. During the first-year follow-up, the ablation volume significantly shrinked. Also, there were no serious complications, and no local tumor progression and lymph node metastasis were observed.