Objective to compare the advantages and disadvantages of robotic and conventional endoscopic thyroidectomy for thyroid cancer.

To compare the difference of operative time and complication between two operative methods in robot neck surgery and routine endoscopic surgery.

Inclusion Criteria:

1. papillary thyroid carcinoma with clinically suspected or confirmed lateral lymph node metastasis;
2. patient's concerns of neck scars and cosmetic requirement.

The exclusion criteria were as follows:

1) tumor size >4cm; 2) previous neck surgical history； 3）residual or recurrent tumors; 4) suspicious primary tumor or metastatic lymph node invasion of major vascular structures or recurrent laryngeal nerve.

5）metastatic lymph nodes occurred below the sternoclavicular joint.