• Voluntarily enroll and sign a written informed consent form;

• Age\>=18 years old,\<=80 years old, regardless of gender;

• Locally advanced differentiated thyroid carcinoma (DTC) diagnosed by pathological histology;

• Locally advanced DTC is defined as meeting at least one of the criteria: surgery is expected to be difficult to complete R0/R1 resection; AJCC defined T4 stage: any size of tumor infiltrating beyond the thyroid capsule to the subcutaneous soft tissue, throat, trachea, esophagus, recurrent laryngeal nerve, tumor invades the prevertebral fascia or surrounds the carotid or mediastinal vessels.

• Voluntarily undergo tumor biopsy/operation at enrollment and exit.

• Have not received any anti-tumor treatment in the past;

• According to the evaluation criteria for the efficacy of solid tumors (RECIST version 1.1), there should be at least one imaging measurable lesion. Lesions located within the radiation field of previous radiotherapy can be considered measurable if confirmed to have progressed;

• The physical condition (PS) score of the Eastern Cancer Collaborative Group (ECOG) is 0-2 points;

• Expected survival time\>3 months;

⁃ Female patients with fertility (referring to those who have not undergone menopause or surgical sterilization) must have a negative serum pregnancy test result within 7 days before the study drug administration;

⁃ Female or male patients with fertility must take reliable contraceptive measures during the study drug use period and within 60 days after the last medication use;

⁃ Normal function of major organs, i.e. meeting the following criteria: Blood routine examination (no blood transfusion or G-CSF used within 14 days prior to screening): a) Hemoglobin\>=90 g/L; b) Absolute neutrophil count (ANC)\>=1.5 × 109/L; c) Platelet count\>=80 × 109/L; Blood biochemistry test (no albumin used within 14 days prior to screening): d) Total bilirubin\<=1.5 x Upper limit of normal value (ULN); e) Aspartate aminotransferase (AST) and alanine aminotransferase (ALT)\<=2.5 x ULN (ALT or AST\<=5 x ULN allowed for subjects with liver metastasis); f) Creatinine\<=1.5 x ULN; Coagulation function: g) International standardized ratio (INR) or prothrombin time (PT)\<=1.5 x ULN; h) Activated partial thromboplastin time (APTT)\<=1.5 x ULN; Others: i) Urinary protein\<2+(if urinary protein\>=2+, 24-hour urine protein quantification can be performed, and 24-hour urine protein quantification\<1.0g can be included in the group).j)Myocardial enzyme profiles were within the normal range (simple laboratory abnormalities not clinically significant were also allowed to be included)