Anlotinib or Penpulimab in Combination With RAI for DTC

Inclusion Criteria: * local advanced or metastatic differentiated thyroid cancer (DTC) * scheduled to receive RAI treatment. * absence of good remission of RAI or may not get satisfactory remission from RAI treatment * At least one measurable lesion, with diameter ≥ 10mm measured by spiral MRI/CT scan per RECIST1.1. * Be 18 years of age or older, ECOG PS: 0-2. Life expectancy of at least 6 months. * Main organs function is normal. * The woman patients of childbearing age who must agree to take contraceptive methods (e.g. intrauterine device, contraceptive pill or condom) during the research and within another 6 months after it; who are not in the lactation period and examined as negative in blood serum test or urine pregnancy test within 7 days before the research; The man patients who must agree to take contraceptive methods during the research and within another 6 months after it. Exclusion Criteria: * Patients who had previously received treatment with Antiangiogenic tyrosine kinase inhibitors, such as: Anlotinib, apatinib and Lenvatinib. * Patients who had previously received local treatment within 4 weeks or Participated in other anti-tumor clinical trials within 4 weeks. * Patients with previous or current concurrent malignancies or solid organs or bone marrow transplants within 5 years. Exceptions include basal cell carcinoma of the skin, squamous cell carcinoma of the skin, or in situ cervical cancer that has undergone potentially curative therapy * Unmitigated ≥ grade 2 toxicity (CTC AE 5.0) due to any prior treatment, excluding alopecia. * With kinds of factors which affect oral medicine (e.g. failing to swallow, gastrointestinal tract getting resected, chronic diarrhea and ileus) * Patients with pleural effusion or ascites. * Patients with any severe and/or uncontrolled disease. * Patients who underwent major surgery, open biopsy or significant traumatic injury within 4 weeks. * Regardless of the severity, patients with any physical signs or history of bleeding, patients with bleeding or bleeding events greater than or equal to CTCAE 2 within four weeks prior to the first administration, or patients with unhealed wounds, fractures, ulcers. * Patients with arterial or venous thromboembolic events occurred within 6 months, such as cerebrovascular accident (including transient ischemic attack), deep vein thrombosis and pulmonary embolism.