The incidence of thyroid cancer is increasing year by year. It is insidious and has almost no symptoms in the early stage, and many patients are detected by physical examination. Thyroid cancer is classified into papillary carcinoma, follicular carcinoma, medullary carcinoma, undifferentiated carcinoma, lymphoma and metastatic carcinoma according to the pathological types. The less malignant ones, including papillary carcinoma and follicular carcinoma, which account for 92% of the cases, are called “differentiated thyroid cancer” and can be treated with internal irradiation with isotopes (radioactive iodine) even if they have metastasized, regardless of the part of the body to which they have metastasized. Differentiated thyroid cancer, especially papillary carcinoma, can be treated satisfactorily in most patients with total or near-total surgical excision, radioactive iodine therapy, and levothyroxine T4TSH suppression therapy. According to a study in Japan, the metastasis rate of papillary thyroid cancer is 1% in 5 years and 5% in 10 years, and no post-operative re-metastasis was observed when metastasis was found and then operated. Therefore, once you suspect a malignant thyroid nodule, you should not be nervous and go to the hospital for regular examination and reasonable treatment. Secondly, you can’t go to the extreme of thinking that the disease is fine and leave it alone, which will lose a good chance of treatment.