It is possible that thyroid cancer has not metastasized twenty years after surgery. Most thyroid cancers are less malignant, with a high five-year survival rate, and most patients have the chance of radical treatment by surgery. If the surgical resection is thorough, and there is no metastasis in lymph nodes and other parts of the body, and the lymph nodes in the corresponding area are thoroughly cleared during the surgery, it is possible to achieve a very good prognosis. It is also related to the type of thyroid cancer and the patient’s own condition. The chances of recurrence of metastasis of thyroid cancer generally need to be decided according to one’s own situation and the type of cancer. Generally speaking, papillary thyroid cancer or follicular thyroid cancer is of low malignant degree and the chance of recurrence is relatively low; but medullary thyroid cancer or undifferentiated thyroid cancer has a higher chance of recurrence. Therefore, it is necessary to go to the hospital for rechecking regularly after surgical resection, so as to find out whether the cancer cells have spread or metastasized in time and reduce the chance of surgical recurrence. Iodine 131 treatment is sometimes needed after thyroid cancer surgery. After the disease is stabilized, regular rechecks are needed, and once metastasis is found, one should actively cooperate with the doctor for treatment.