Preoperative ultrasound of the neck is routinely performed to understand the possibility of lymph node metastasis in the neck, and enhanced CT of the neck is also recommended to clarify whether there is lymphatic metastasis in the lateral neck area. If the possibility of metastasis is highly suspected by ultrasound or enhanced CT, further fine needle aspiration is recommended to provide a reasonable basis for surgery, usually at least unilateral thyroidectomy plus lymph node dissection in the central region. If there are lymph nodes in the lateral cervical area, the left cervical lymph node dissection should be added. Preoperative CT chest examination should be completed to exclude the possibility of combined lung metastasis. After surgery, if there is metastasis, further iodine-131 treatment is needed according to the situation. Iodine-131 can clarify whether there is a combination of distant metastasis elsewhere and achieve the purpose of treatment and examination.