Neoadjuvant Treatment of Tislelizumab Combined Chemotherapy for Locally Advanced Oral Squamous Cell Carcinoma ：A Single-arm, Prospective, Phase II Trial

Inclusion Criteria:

1. Signed the informed consent form
2. Histopathological diagnosis of oral squamous cell carcinoma
3. Age: 18-75 years old , Gender: male and female
4. Primary tumor with a clinical stage of III/IVb (T1-2N+M0或T3-4N0-3M0, AJCC2018)
5. Eastern Cooperative Oncology Group (ECOG) performance status (PS): 0-1
6. No previous systematic therapy for OSCC (including chemotherapy, EGFR inhibitors, VEGFR inhibitors such as bevacizumab, immune checkpoint inhibition such as anti-PD-1 or PD-L1 antibodies, anti-ctLA-4 antibodies, etc.);
7. Patients must have at least one measurable lesion according to the Response Evaluation Criteria in Solid Tumors (RECIST v1.1)
8. Adequte organ function based on laboratory test values obtained during the screening period：1）Blood routine: white blood cells (WBCs) \>3.0× 109/L, ANC \>1.5× 109/L, platelets \>75× 109/L, hemoglobin \>9 g/L, 2）Liver function: alanine amino transferase/aspartate amino transferase (ALAT/ASAT) \<2.5 times the upper limit of normal and bilirubin \<1.5 times the upper limit of normal，3）Renal function: Serum creatinine \<1.5 times the upper limit of normal，4）Coagulation function: INR, PT, APTT\<1.5 times the upper limit of normal，5）Left ventricular ejection fraction (LVEF) ≥ 50%
9. contraception

Exclusion Criteria:

1. Known history of malignancy, unless been cured and no recurrence for 5 years
2. Patients with a history of active bleeding, coagulopathy, or receiving coumarin anticoagulation therapy
3. Known history of radiation, chemotherapy, surgery and immunology-based treatment to head and neck
4. Active autoimmune disease requiring systemic treatment within 2 years prior to the first dose, or autoimmune disease that may recur or plan treatment as judged by the investigator.
5. Active or previous definite inflammatory bowel disease (e.g., Crohn 's disease or ulcerative colitis) disease.
6. Subjects with known active pulmonary tuberculosis (TB) and suspected active TB require clinical examination to rule out; known active syphilis infection.
7. Serious infections within 4 weeks prior to the first dose, including but not limited to comorbidities requiring hospitalization, sepsis, or serious pneumonia; active infections (excluding antiviral therapy for hepatitis B or C) that have received systemic anti-infective therapy within 2 weeks prior to the first dose.
8. Known human immunodeficiency virus (HIV) infection
9. Subjects with untreated active hepatitis B (HBsAg positive and HBV-DNA more than 1000 copies/ml \[200 IU/ml\] or above the lower limit of detection) and anti-hepatitis B virus treatment during study treatment are required for subjects with hepatitis B; subjects with active hepatitis C (HCV antibody positive and HCV-RNA level above the lower limit of detection).
10. History of pneumonitis/interstitial lung disease requiring systemic corticosteroids or current pneumonitis.
11. Known allergic reaction to any ingredients or excipients of the therapy
12. Participation in other clinical trials within 30 days before enrollment
13. Pregnant or lactating women
14. Known alle Other situations that the investigator considers unsuitable with respect to participating in the trial