Thyroid cancer survival time varies greatly after treatment. Depending on the pathologic type and stage of thyroid cancer, it can be divided into differentiated thyroid cancer as well as medullary thyroid cancer, and there is a significant difference in survival between medullary thyroid cancer and undifferentiated thyroid cancer. The differences in survival are as follows. 1. Differentiated thyroid cancer: including papillary thyroid cancer and follicular thyroid cancer, which is common in clinic and has a better prognosis. The survival period of this kind of thyroid cancer is relatively good. After active and effective treatment, the 5-year survival rate can reach more than 90%, and many patients can survive for a long time. 2. Medullary thyroid cancer and undifferentiated thyroid cancer: these two kinds of thyroid cancers have higher malignancy and earlier metastasis. Medullary carcinoma has a longer course, up to 10-20 years, and the median survival period after treatment is about 10 years; undifferentiated carcinoma has a very high degree of malignancy, and although it is rare in clinical practice, the prognosis is very poor, and the survival time is only a few months for most people. Early detection, early diagnosis and early treatment of thyroid cancer can improve the survival rate of patients, and it is important not to be negligent, so as not to cause delay.