Differentiated thyroid carcinoma such as papillary carcinoma and follicular carcinoma are mainly treated by surgery, supplemented by tsh suppression therapy and iodine 131 after surgery. Medullary carcinoma, on the other hand, is mainly treated by surgery only, combined with RET gene test to be performed prophylactically, without suppressive therapy and chemoradiotherapy, and iodine 131 is not effective. External radiotherapy is usually used for patients with advanced thyroid cancer who have no way to operate. The attached picture shows a medullary carcinoma treated in an external hospital with only a mass cut, followed by more than thirty times of external radiotherapy, which led to local adhesions and made it very difficult and risky for us to operate again.