Becotatug Vedotin Combined With Pucotenlimab as Neoadjuvant Therapy for Resectable Recurrent Head and Neck Squamous Cell Carcinoma After Progression on Immunotherapy: A Prospective Phase II Study

INCLUSION CRITERIA: 1. Eastern Cooperative Oncology Group (ECOG) performance status 0-1 2. Age 18-75 years at time of consent 3. Histologically or cytologically confirmed recurrent head and neck squamous cell carcinoma 4. Disease progression after prior treatment including both PD-1/PD-L1 inhibitor and platinum-based therapy (combined or sequential) 5. EGFR protein expression positive by immunohistochemistry (IHC), with no EGFR-targeted therapy within 6 months prior to enrollment 6. Willing to provide archived tumor tissue or undergo fresh tumor biopsy for EGFR testing 7. At least one measurable extracranial lesion per RECIST v1.1; previously treated lesions must demonstrate clear progression 3 or more months after last local treatment 8. Resectable disease with no distant metastasis, as assessed by a multidisciplinary team 9. Adequate organ function within 7 days prior to enrollment: ANC at least 2.0 x 10\^9/L, platelet count at least 100 x 10\^9/L; total bilirubin less than 1.5 x ULN, ALT/AST less than 2.5 x ULN; serum creatinine less than 1.5 x ULN 10. Signed informed consent prior to any study-specific procedures 11. Life expectancy greater than 3 months 12. Effective contraception during study and for 6 months after last dose EXCLUSION CRITERIA: 1. History of other malignancies (except cured basal cell carcinoma or cervical carcinoma in situ) 2. Comorbidities requiring long-term immunosuppressive therapy or corticosteroids at immunosuppressive doses 3. Immunodeficiency or history of organ transplantation (including interstitial pneumonia, hepatitis, nephritis, hyperthyroidism, hypothyroidism) 4. HIV/AIDS; untreated active hepatitis B (HBV-DNA at least 500 IU/mL); hepatitis C (HCV-RNA above detection limit); or HBV/HCV co-infection 5. High-dose systemic corticosteroids within 4 weeks prior to enrollment 6. Pregnant or lactating women; fertile patients not using effective contraception 7. Laboratory values not meeting inclusion criteria within 7 days 8. Significantly impaired cardiac, hepatic, pulmonary, renal, or bone marrow function 9. Severe uncontrolled comorbidities or active infections 10. Concurrent participation in other clinical trials 11. Refusal or inability to sign informed consent 12. Other contraindications to study treatment as determined by the investigator 13. Psychiatric disorders or mental illness resulting in lack of legal capacity