研究目的:
                        
                            Head and neck squamous cell carcinoma (HNSCC) refers to a series of tumors that occur in  the head and neck region, including the oral cavity, pharynx, larynx, nasal cavity,  paranasal sinuses, thyroid gland, and salivary glands. Malignant tumors of the head and  neck account for approximately 19.9% to 30.2% of all tumors in the body, ranking sixth in  incidence among all malignant tumors, with over 90% being squamous cell carcinoma in  terms of pathological type. The treatment of head and neck squamous cell carcinoma is  primarily surgical. Early-stage cases can achieve a cure through simple surgical  resection or radiotherapy. For locally advanced and late-stage cases, a combination of  surgery with radiotherapy or chemotherapy can yield satisfactory therapeutic effects.  However, most patients with head and neck tumors present at a locally advanced (Stage III  to IVB) or late stage, possibly having lost the opportunity for surgery and can only opt  for a comprehensive treatment mainly based on radiochemotherapy. Current data show that  with standard treatment, the 5-year survival rates for patients with early-stage, locally  advanced, and metastatic head and neck squamous cell carcinoma are 80%, 50%, and 25%,  respectively. Fifty to sixty percent of newly diagnosed subjects cannot be cured and  experience recurrence or metastasis within 3 years. For patients with recurrent or  metastatic disease after first-line treatment failure, the median survival time with  chemotherapy is only 6 to 9 months, with a 1-year survival rate of 5% to 33% and a 5-year  survival rate of merely 3.6%. Laryngeal cancer and hypopharyngeal cancer hold unique  significance among head and neck tumors because they not only threaten patients' lives  but can also significantly affect their quality of life, particularly the preservation of  laryngeal function. Laryngeal function includes voice production, swallowing, and  breathing, and the loss of these functions can lead to a severe decline in quality of  life. Traditionally, surgical resection has been the main treatment for these cancers,  but total laryngectomy can result in permanent voice loss and significant psychological  and social impacts. Therefore, how to effectively control the tumor while preserving  laryngeal function has become an important goal of treatment.    PD-L1 is a key negative regulator of self-reactive T cells and plays a role in  maintaining peripheral immune tolerance and suppressing autoimmunity in various ways,  leading to T cell exhaustion and dysfunction, and allowing tumor cells to evade immune  surveillance. PD-1/PD-L1 monoclonal antibodies restore the function of tumor-specific T  cells by blocking the binding of PD-1 to PD-L1, thereby enhancing antitumor immunity and  are now used to treat a variety of tumors. The efficacy of PD-1 inhibitors as neoadjuvant  therapy in head and neck squamous cell carcinoma is not yet clear. However, given the  good therapeutic effects of immunotherapy in head and neck squamous cell carcinoma,  induction therapy with PD-1 inhibitors is considered to have promising clinical  application prospects.    In summary, we hypothesize that compared with the traditional TPF (docetaxel, cisplatin,  and fluorouracil) neoadjuvant chemotherapy regimen, a PD-1 inhibitor combined with  chemotherapy regimen may be safer and more effective and easier to apply in clinical  practice. At present, there are no reports of studies on the use of PD-1 inhibitors  combined with chemotherapy regimens for locally advanced, resectable head and neck  squamous cell carcinoma patients, either domestically or internationally. We plan to  investigate the efficacy and safety of neoadjuvant treatment with PD-1 inhibitors  combined with chemotherapy for resectable head and neck squamous cell carcinoma patients  in China, to provide a basis for future neoadjuvant treatment regimens.