Tisleilizumab (PD-1 Antibody) and Chemoradiotherapy in Locoregionally-advanced Nasopharyngeal Carcinoma

Inclusion Criteria: \- Patients with histologically confirmed nasopharyngeal carcinoma. Stage T4N1 or T1-4N2-3 (AJCC 8th). Eastern Cooperative Oncology Group performance status ≤1. Adequate marrow function: neutrocyte count≥1.5×10e9/L, hemoglobin ≥90g/L and platelet count ≥100×10e9/L. Alanine Aminotransferase (ALT)/Aspartate Aminotransferase (AST) ≤2.5×upper limit of normal (ULN), and bilirubin ≤ 1.5×ULN. Adequate renal function: creatinine clearance rate ≥ 60 ml/min (Cockcroft-Gault formula). Patients must be informed of the investigational nature of this study and give written informed consent. Women of childbearing potential (WOCBP) who are sexually active must be willing to adhere to effective contraception during treatment and for 1 year after the last dose of study drug. Men who are sexually active with WOCBP must be willing to adhere to effective contraception during treatment and for 1 year after the last dose of the study drug. Exclusion Criteria: Hepatitis B surface antigen (HBsAg) positive and hepatitis B virus DNA \>1×10e3 copies/ml or 200IU/ml;Hepatitis C virus (HCV) antibody positive Has active autoimmune disease, except type I diabetes, hypothyroidism treated with replacement therapy, and skin disease that doesn't require systemic treatment (e.g., vitiligo, psoriasis, or alopecia). Has any condition that required systemic corticosteroid (equivalent to prednisone \>10mg/d) or other immunosuppressive therapy within 28 days before informed consent. Patients received systemic corticosteroid equivalent to prednisone ≤10mg/d, inhale or topical corticosteroid will be allowed. Has a known history of active TB (bacillus tuberculosis) within 1 year; patients with adequately treated active TB over 1 year ago will be allowed. Has a known history of interstitial lung disease. Heart disease that is not well controlled,including symptomatic heart failure, unstable angina, myocardial infarction. Is pregnant or breastfeeding. Prior malignancy within 5 years, except in situ cancer, adequately treated non-melanoma skin cancer, and papillary thyroid carcinoma. Has known allergy to large molecule protein products or any compound of tisleilizumab. Has a known history of human immunodeficiency virus (HIV) infection. Active infection requiring systemic therapy. A history of psychotropic substance abuse, alcohol or drug abuse Any other condition, including mental illness or domestic/social factors, deemed by the investigator to be likely to interfere with a patient's ability to sign informed consent, cooperate and participate in the study, or interferes with the interpretation of the results.