Inclusion Criteria:
* The subjects were included in this study and signed the informed consent form.
* Male or female patients aged between 18 and 75 years old;
* Patients diagnosed with esophageal squamous cell carcinoma by histopathology;
* According to the 8th edition of the AJCC Esophageal cancer TNM staging system, it is located in cT2N+ or cT3-4aNanyM0 (confirmed by enhanced CT/MRI of the chest and abdomen), and the lesion is located in the thoracic segment.
* ECOG score: 0-1.
* The main organs function normally, that is, they meet the following standards:
1. Blood routine (no blood transfusion was performed within 14 days before treatment, no granulocyte colony-stimulating factor \[G-CSF\] was used, and no other drugs were used for correction);
The absolute neutrophil count (ANC) was ≥1.5×109/L;
Hemoglobin (HB) ≥9.0 g/dL;
Platelet count (PLT) ≥100×109/L;
2. Blood biochemistry
Creatinine clearance rate ≥60 mL/min;
Total bilirubin (TBIL) ≤ 1.5×ULN;
Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) level ≤2.5×ULN;
* The expected survival period is ≥3 months;
* Female subjects with reproductive capacity and male subjects whose partners are of childbearing age need to adopt a medically approved contraceptive measure during the study treatment period and for at least 3 months after the last treatment
Exclusion Criteria:
* There are clinically uncontrolled pleural effusions, pericardial effusions or ascites that require repeated drainage or medical intervention (within 2 weeks before randomization);
* It is known that there is intolerance or resistance to the chemotherapy specified in the trial protocol;
* Have received any other ESCC anti-tumor treatments (e.g., targeted treatments for PD-1, PD-L1, PD-L2, or other tumor immunotherapy, radiotherapy, targeted therapy, ablation, or other systemic or local anti-tumor treatments);
* Patients with active autoimmune diseases or a history of autoimmune diseases that may recur, or a known history of allogeneic organ transplantation or allogeneic hematopoietic stem cell transplantation;
* Have a history of interstitial lung disease, non-infectious pneumonia or uncontrolled systemic diseases, including pulmonary fibrosis, acute lung diseases, etc.
* Before enrollment, there was a severe chronic or active infection (including tuberculosis infection, etc.) that required systemic antibacterial, antifungal or antiviral treatment;
* A known history of HIV infection;
* Having suffered from other malignant tumors within the past five years (excluding cured basal cell carcinoma of the skin, carcinoma in situ of the breast and carcinoma in situ of the cervix);
* Have received live vaccines within 28 days before enrollment;
* Participated in other therapeutic clinical trials within 4 weeks;
* Those that the researchers consider unsuitable for inclusion.
* Distant metastasis exists (except for supraclavicular lymph nodes).
