Genetic testing is necessary after radical thyroid surgery to find out if you have abnormal mutated genes and to determine the chances of malignancy. Undergoing radical thyroid surgery indicates that malignant thyroid disease has occurred or the possibility of malignant thyroid disease exists, at which point genetic testing can be performed. If the results of the genetic test are found to be abnormal, it means that malignant lesions are more likely and early intervention is needed. If the results of the genetic test are normal, it can be relatively reassuring and regular checkups are sufficient. When patients have undergone radical thyroid surgery, it is recommended that they go to the hospital and consult a professional doctor to determine whether genetic testing is necessary according to their situation. After surgery, it is important to take sufficient rest, avoid exertion, relax and promote the health of the thyroid gland.