A Multicenter Trial of Radiofrequency Ablation vs. Surgery as Treatment of Papillary Thyroid Microcarcinoma.
A Multicenter Trial of Radiofrequency Ablation vs. Surgery as Treatment of Papillary Thyroid Microcarcinoma.
The treatment of Papillary Thyroid Microcarcinoma (PTMC) nowadays varies among physicians,
 surgeons and radiologist. The recently published articles show that the prognosis of PTMC by
 different means of treatment strategies tends to be good. But multicentered, randomized,
 parallel and prospective study is rare. RFA is the abbreviation of "Radiofrequency Ablation",
 which tends to be an alternative strategy except conventional surgery. The investigator aims
 to confirm whether RFA for treating PTMC braces same effectiveness and prognosis comparing
 with conventional surgery. Besides, this trial also investigates the safety, economy and
 psychological quality under different treatments.
The incidence of thyroid carcinoma, especially the papillary thyroid microcarcinoma (PTMC),
 has increasingly rapidly, due to the development of technologies of diagnosis, during the
 past 20 years. PTMC defined by the World Health Organization (WTO) as the largest dimension
 less than 1 cm. Previous autopsy study demonstrated that the lesions are normal in many
 people and accompany them latently until they die because of another reasons. The long-term
 outcome of PTMC is good and, as expected, more than 90% PTMC aren't progress for many years.

 Ultrasound-guided Radiofrequency Ablation (RFA) treatment was introduced to clinical practice
 few years ago. According to the 2015 American Thyroid Association (ATA) guideline, the
 treatment of radiofrequency and laser ablation are mentioned to be used in recurrent thyroid
 cancer. But clinical practice shows that the RFA treatment for low risk PTMC braces well
 effect，low financial budget，high safety and even rare postoperative complication.

 Although the cohort study was performed before, the real answer concerning about whether RFA
 is a rational choice for treating PTMC lacks more powerful evidences. The investigator
 considers to perform a randomized, controlled and multicenter study as a high-quality
 evidence and demonstrated the effect of PRF in low risk PTMC treatment.
Inclusion Criteria:

 -  Newly diagnosis of PTMC (largest dimension<10mm)

 -  Age >=18 years old

 -  Bethesda Category V or VI

 -  Single nodule without thyroid capsule contact

 -  Nodule has more than 3mm distance far from recurrent laryngeal nerve, carotid artery
 and trachea.

 -  No clinical evidences show there is local or distant metastasis.

 -  Without chemotherapy, radiotherapy and other related therapies.

 -  Patients and their family member totally understand and sign the informed consent.

 Exclusion Criteria:

 -  Multifocal PTMC

 -  Combined with other types of thyroid cancer or hyperthyroidism.

 -  Contralateral vocal cord paralysis

 -  With local or distant metastasis

 -  Pregnant woman

 -  With radiation exposure history