Undifferentiated thyroid cancer is a group of very poorly differentiated and highly malignant types of thyroid cancer, including giant cell carcinoma, small cell carcinoma, rhombic cell carcinoma, squamous carcinoma, adenoid cystic carcinoma, mucinous carcinoma, and a few poorly differentiated follicular or papillary carcinomas. The incidence of thyroid cancer accounts for 5%-15% of all thyroid cancers. If undifferentiated thyroid cancer is diagnosed, the overall effect of treatment is very poor, generally speaking, the one-year survival rate is less than 10%, and 90% of patients cannot survive for more than one year. Therefore, there are not many treatment methods and the results are not particularly good after the diagnosis of this disease.