De-escalated Radiotherapy for Primary Tumor After Neoadjuvant Therapy With Toripalimab Plus Chemotherapy for Nasopharyngeal Carcinoma

Inclusion Criteria: 1. Pathologically confirmed nasopharyngeal carcinoma, patients who have not received anti-cancer therapy; 2. ECOG performance status score (PS score) 0 or 1. 3. 18-70 years old. 4. Stage II-III except T2N0M0 (AJCC 8th). 5. Neutrophil count ≥ 1.5 × 10\^9/L, hemoglobin ≥ 90 g/L and platelet count ≥ 100 × 10\^9/L. 6. Alanine aminotransferase (ALT)/aspartate aminotransferase (AST) ≤ 2.5 times the upper limit of normal (ULN), bilirubin ≤ 1.5 times ULN; Creatinine clearance ≥ 60 ml/min 7. Patients are required to sign an informed consent form and must be willing and able to comply with the visits, treatment plan, laboratory tests, and other requirements specified in the study protocol Exclusion Criteria: Patients will be excluded from the study, if any of the following criteria is met: 1. Over the age of 70 or under the age of 18. 2. HBsAg positive and HBV DNA ≥ 1 × 10\^3 copies/ml 3. HCV antibody positive. 4. Subjects with active, known or suspected autoimmune diseases were excluded from the study. Eligible participants included those with type 1 diabetes mellitus, hypothyroidism requiring only hormone replacement therapy, and skin conditions that do not require systemic therapy such as vitiligo, psoriasis, or alopecia. 5. History of interstitial lung disease; 6. Receiving systemic sex hormones or other immunosuppressive therapy at equivalent doses ≥ 10 mg prednisone/day within 28 days prior to signing informed consent; Subjects with systemic sex hormone doses ≤ 10 mg prednisone/day or inhaled/topical corticosteroids were eligible. 7. Received or about to receive live vaccines within 30 days before signing the informed consent form; 8. Pregnant or lactating women; 9. Other malignancies within 5 years, except carcinoma in situ, adequately treated non-melanoma skin cancer and papillary thyroid cancer; 10. Known previous hypersensitivity to macromolecular protein preparations, or to any component of Toripalimab; 11. Human immunodeficiency virus (HIV) infection. 12. Other conditions that may affect the safety of subjects or trial compliance as judged by the investigator, including symptomatic heart failure, unstable angina pectoris, myocardial infarction, active infection requiring systemic treatment, mental illness or family and social factors;