A Prospective, Open-label, Multicenter, Randomized Controlled Phase III Study of Prophylactic Central Neck Dissection in Low-risk Papillary Thyroid Cancer

papillary thyroid carcinoma (PTC) is the most common thyroid cancer and has a good prognosis. Surgery is the primary treatment for PTC, and occult lymph node metastasis is not uncommon (20%-80%).The lymph node metastasis of PTC is mostly along the lymphatic drainage path station by station, and most of the first metastasis is to the central lymph node. According to the 2015 American Thyroid Association recommendation, prophylactic central lymph node dissection is recommended for patients with primary T3-4 or cN1b without central lymph node involvement. However, PTC with primary site T1-2, no external invasion and cN0 could not be dissected by central lymph node.Previous studies have suggested that prophylactic dissection should be performed to improve disease-specific survival, reduce local recurrence, improve recurrence risk and treatment response assessment, and help RAI decision making. Although routine prophylactic central lymph node dissection may detect occult lymph node metastasis, the need for further dissection of the recurrent laryngeal nerve and the parathyroid gland may lead to an increased incidence of complications, while its effect on reducing the risk of recurrence and improving prognosis is unclear, and the impact on long-term outcomes may be small.Previous retrospective studies in our institution have shown that routine central neck dissection does not significantly reduce the risk of recurrence. This study was designed to evaluate the benefits and risks of prophylactic central lymph node dissection in cT1b-T2N0 patients with papillary thyroid carcinoma. In order to ameliorate the effects of relapse and long time of death of PTC, thyroglobulin and its antibodies were also evaluated for short-term treatment response after surgery.