GAPP Induction and Concurrent Chemoradiotherapy Followed by Toripalimab Maintenance for Nasopharyngeal Carcinoma.

Inclusion Criteria:

* Voluntarily participate in and sign informed consent in person.
* Age 18-65, male or non-pregnant female.
* Pathological diagnosis of nasopharyngeal non-keratonic carcinoma (differentiated or undifferentiated, i.e., WHO type II or III).
* First treatment patients who did not receive antitumor therapy had no history of other malignant tumors;
* Stage IVa: TanyN3M0/T4N0-2M0 (8th AJCC/UICC stage)
* ECOG score 0-1, no serious dysfunction of heart, lung, liver, kidney and other vital organs.
* Hemoglobin (HGB) ≥90 g/L, white blood cells (WBC) ≥4.0×109 /L, platelets (PLT) ≥100×109 /L.
* Liver function: ALT and AST\< 2.5 times the upper limit of normal (ULN), total bilirubin \<2.0×ULN.
* Renal function: serum creatinine \<1.5×ULN.

Exclusion Criteria:

* Patients with recurrent and distant metastasis of nasopharyngeal carcinoma.
* The pathology was keratinized squamous cell carcinoma (WHO type I).
* Received systemic or local glucocorticoid therapy within 4 weeks prior to enrollment.
* Participants who had participated in other drug clinical trials within 3 months before treatment.
* Patients with a known history of allogeneic organ transplantation or allogeneic hematopoietic stem cell transplantation;
* Patients with idiopathic pulmonary fibrosis, drug-induced pneumonia, institutional pneumonia (i.e., bronchiolitis obliterans), radiation pneumonia with clinical symptoms or requiring steroid treatment, active pneumonia, or other moderate to severe lung diseases that seriously affect lung function
* Have a comorbiditis that requires long-term treatment with immunosuppressive drugs or systemic or local use of immunosuppressive doses of corticosteroids.
* Prior use of anti-PD-1 antibodies, anti-PD-L1 antibodies, anti-PD-L2 antibodies, or anti-CTLA-4 antibodies (or any other antibody that acts on the T-cell co-stimulation or checkpoint pathway), and efficacy was assessed as progressive at enrollment.
* The subject has any active autoimmune disease or history of autoimmune disease (including but not limited to: interstitial pneumonia, uveitis, enteritis, hepatitis, hypophysitis, nephritis, hyperthyroidism, hypothyroidism; Patients with vitiligo or who had complete remission of asthma in childhood and did not require any intervention as adults were included; Patients with asthma requiring medical intervention with bronchodilators were not included).
* Positive HBV DNA copy number was detected in HIV-positive patients and HBsAg positive patients (quantitative detection ≥ 1000cps/ml); Chronic hepatitis C blood screening positive (HCV antibody positive) with HCV RNA positive detection.
* Received any anti-infection vaccine (such as influenza vaccine, chickenpox vaccine, etc.) within 4 weeks before enrollment.
* Pregnancy test positive women of childbearing age and breastfeeding women.
* Patients who are unable to cooperate with regular follow-up due to psychological, social, family and geographical reasons.