Thyroid cancer, as a malignant tumor, will spread and metastasize if left untreated, such as lymph node metastasis, lung metastasis, and bone metastasis. Once the lump increases in size, it will also invade the surrounding tissues. With the location of thyroid gland in front of the neck, there is also the possibility of invasion to the esophagus behind or compression of the trachea. As the tumor increases in size or invasion or metastasis, a series of symptoms will occur, such as compression of the trachea, which will cause difficulty in breathing or swallowing, and if the nerves are invaded, there will also be obvious hoarseness, and if there is lung metastasis, there is the possibility of coughing or frequent infection. Thyroid cancer is a systemic malignant tumor that must need treatment. Treatment includes surgery, endocrine therapy, radiotherapy, and the common and most important one is a comprehensive treatment mainly based on surgery. Surgery should be judged according to the tumor condition, including the extent of thyroid gland removal and lymph node clearance, which are decided according to the characteristics of the tumor. Radiotherapy and endocrine therapy are to inhibit the recurrence and metastasis of the tumor.