Toripalimab ± Chemo as Neoadjuvant Therapy in LA-HNSCC: A Phase III Trial

Inclusion Criteria: * Pathologically confirmed, newly diagnosed, non-metastatic, operable locally advanced head-and-neck squamous cell carcinoma (oral cavity, larynx, hypopharynx, or oropharynx) Stage III-IVA (p16-positive oropharynx T4N0-N2; p16-negative oropharynx III-IVA; larynx/hypopharynx/oral cavity III-IVA) PD-L1 CPS ≥ 1 Age 18-70 years ECOG performance status 0-1 Adequate organ function (ANC ≥ 2.0×10⁹/L, platelets ≥ 100×10⁹/L, TBIL \< 1.5×ULN, ALT/AST \< 1.5×ULN, creatinine \< 1.5×ULN) No prior head-and-neck cancer surgery or radiotherapy No other malignancy within 5 years Signed informed consent Exclusion Criteria: * Previous systemic anti-cancer therapy for head-and-neck cancer Known hypersensitivity to study drugs Active or untreated hepatitis B/C, HIV positivity Severe cardiac, pulmonary, liver, or renal insufficiency precluding surgery Pregnancy or lactation Psychiatric or social conditions preventing compliance Organ transplant on chronic immunosuppression