This study was a single-center, single-arm, open-label phase II clinical trial. Thirty patients with unresectable locally advanced or postoperative recurrent esophageal squamous cell carcinoma were treated with concurrent chemoradiotherapy combined with immunotherapy. The radiotherapy regimen was intensity-modulated radiotherapy with PGTV at 50-50.4 Gy/25-28 fractions, 1.8-2 Gy per fraction, five times a week. The chemotherapy regimen was paclitaxel 50 mg/m2 and cisplatin 25 mg/m2 intravenous infusion on day 1, once a week for five times. The immunotherapy was with adebutilimab at 20 mg/kg on day 1, every three weeks for three times. One week before radiotherapy, gastroscopy, chest CT or PET-CT images were taken as the baseline standard. Based on the results of gastroscopy, chest CT or PET-CT before and after treatment, the number of patients with complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD) in the two groups was observed. The objective response rate (ORR) was calculated as CR + PR, and the disease control rate (DCR) was calculated as CR + PR + SD. The progression-free survival (PFS), overall survival (OS), 1-year and 2-year survival rates and adverse reactions were also statistically analyzed.

Inclusion Criteria:

1. Age 18-75 years old, gender unlimited
2. Esophageal squamous cell carcinoma confirmed by histology and unresectable locally advanced or postoperative recurrence
3. According to the solid tumor efficacy evaluation criteria (RECIST1.1), there is at least one measurable lesion; And the lesion had not received prior radiotherapy
4. ECOG: 0~1
5. Expected survival ≥12 weeks 6. Laboratory examination: neutrophils ≥1.5 x 109/L, platelets ≥100 x 109/L; Hemoglobin ≥ 9g/L; Albumin ≥ 2.8g/dL; Bilirubin ≤1.5 times ULN, ALT and AST≤2.5 times ULN

7: Subjects voluntarily joined the study, signed informed consent, had good compliance, and cooperated with follow-up 8: Tissue samples should be provided for biomarker analysis such as (PD-L1). Newly acquired tissues are preferred, and 15 5-6um thick paraffin sections can not be provided for archiving by the recent organizer

Exclusion Criteria:

1. Other malignant tumors have been diagnosed within the previous 5 years
2. There is distant organ metastasis (according to AJCC stage, supraclavicular lymph node metastasis is M1, which should be excluded)
3. Lesions invading the trachea or large blood vessels, or investigators judge that there is a high risk of esophageal/tracheal fistula or bleeding
4. Have any history of active autoimmune disease or autoimmune disease
5. Have clinical symptoms or diseases of the heart that are not under control
6. Active infection or fever (except definite tumor fever)
7. History or evidence of interstitial lung disease or active non-infectious pneumonia
8. Patients with immune dysfunction and active hepatitis
9. Those who have previously received PD-1 or PD-L1 antibody therapy
10. Allergic to any drug in this protocol
11. Patients receiving immunosuppressive drugs or corticosteroids >10mg/ day of prednisone therapeutic dose within 14 days prior to enrollment
12. Patients who had received radiotherapy, chemotherapy, targeted therapy, or immunotherapy within 4 weeks prior to enrollment
13. Pregnant or lactating women