There is a certain probability of recurrence after removal of malignant thyroid nodules, and if the recurrence is not treated in time it will definitely spread. In fact, there is a certain risk of recurrence after removal of various malignant tumors, but surgical removal is still the best choice for treating various malignant tumors. The reasons for recurrence after thyroid surgery are mainly several: Firstly, malignant thyroid tumors are more malignant, such as undifferentiated carcinoma or medullary carcinoma, which are more malignant in themselves, so the risk of recurrence after surgery is also higher. Secondly, the post-operative conditioning is not ideal. After thyroid surgery, you have to take Eugenol for life, and some of them also need to cooperate with radiotherapy for a period of time, so if the body’s T3 and T4, including potassium storage, cannot be maintained at a relatively balanced level during the long-term conditioning process, it is likely to stimulate thyroid recurrence. Third, the problem of surgical operation, the need for extensive neck lymph node dissection surgery, if the operator has surgical operation problems, will easily leave residual lymph nodes.