Sintilimab Combination Therapy Plus IMRT in Nasopharyngeal Carcinoma

Inclusion Criteria: * 1\. Sign a written informed consent before implementing any procedures related to the trial; 2. No gender limitation, age ≥18 years old, ≤75 years old; 3. Histological or cytological determination of advanced nasopharyngeal carcinoma assessed by the investigator without any treatment (stage III-IVA, except T3N0M0); 4. Not suitable for platinum therapy (patients \> 70 years old, PS \> 2, hearing impairment, renal insufficiency (creatinine clearance \< 50ml/min) or grade 1 neuropathy;2023 CSCO Guidelines for the Diagnosis and Treatment of Head and Neck Tumors) or patients do not receive platinum therapy; 5. The ECOG PS score is 0-1; 6. According to the solid tumor efficacy evaluation criteria (RECIST version 1.1), there is at least one radiographically measurable lesion; 7. Expected survival time \> 6 months; 8. Adequate organ function. Exclusion Criteria: * 1\. Patients with uncured malignancies other than advanced nasopharyngeal carcinoma diagnosed within 5 years prior to initial administration (excluding radical basal cell carcinoma of the skin, squamous epithelial carcinoma of the skin, and/or carcinoma in situ after radical resection); 2. Is currently participating in an interventional clinical study, or has received other investigational drugs or used investigational devices within 4 weeks prior to initial dosing; 3. Previous treatment with anti-PD-1, anti-PD-L1 or anti-PD-L2 drugs or drugs that target another stimulus or synergistically inhibit T cell receptors (e.g., CTLA-4, OX-40, CD137); 4. Previously received anti-angiogenic therapy, including but not limited to anti-angiogenic monoclonal antibodies, anti-angiogenic TKI, etc.; 5. Received systemic systemic treatment with proprietary Chinese medicines with anti-tumor indications or immunomodulatory drugs (including thymosin, interferon, interleukin) within 2 weeks before the first administration; 6. An active autoimmune disease requiring systemic treatment (e.g. with disease-modifying drugs, glucocorticoids, or immunosuppressants) has occurred within 2 years prior to first administration.Replacement therapies (such as thyroxine, insulin, or physiologic glucocorticoids for adrenal or pituitary insufficiency) are not considered systemic therapy; 7. Known allogeneic organ transplantation (except corneal transplantation) or allogeneic hematopoietic stem cell transplantation; 8. Known active ingredients or excipients of Sintilimab and bevacizumab in this study, and allergic patients to chemotherapy drugs in this study; 9. Has not fully recovered from toxicity and/or complications caused by any intervention before starting treatment (i.e., ≤ grade 1 or baseline, excluding weakness or hair loss); 10. Known history of human immunodeficiency virus (HIV) infection (i.e. HIV 1/2 antibody positive); 11. Other researchers did not consider it appropriate to study enrollment