• Volunteered to participate, cooperated with follow-up visits;

• Aged ≥ 70 years, both male and female;

• Histologically confirmed cT1N2-3M0 or cT2-4bN0-3M0 or cT1-4bN0-3M1(supraclavicular lymph node metastasis) locally advanced ESCC (8th AJCC );

• Clinically staged as II-IVb inoperable locally advanced ESCC(including non-resectable, or with contraindications to or refusal of surgery);

• ECOG performance status 0 or 1;

• Presence of measurable and/or non-measurable lesions as defined by RECIST 1.1;

• Haven't received any previous systemic anti-tumor therapy (including but not limited to systemic chemotherapy, radiotherapy, molecularly targeted drug therapy, immunotherapy, biologic therapy, topical therapy and other investigational therapeutic agents);

• Provide fresh or archived tumour tissue samples within 6 months (fresh samples preferred) for biomarker analysis (e.g.PD-L1). Sample types are formalin-fixed, paraffin-embedded \[FFPE\] tumour tissue blocks or at least 5 unstained, 3-5 μm thick FFPE tumour tissue sections;

• Expected survival ≥ 3 months;

⁃ Adequate hematologic function, defined as ANC ≥1500/μl, platelet count ≥100,000/μl and hemoglobin count ≥9.0 g/dl or ≥5.6 mmol/l;

⁃ Adequate renal function, defined as creatinine ≤1.5× ULN or measured or calculated creatinine clearance ≥60 mL/min for those with creatinine levels \>1.5× ULN (Calculated from the Cockcroft-Gault formula);

⁃ Adequate hepatic function, defined as total bilirubin ≤1.5× ULN and ALT/AST/AKP levels ≤2.5× ULN and albumin ≥2.8 g/dl;

⁃ Adequate coagulation function, defined as INR ≤1.5× ULN and APTT≤1.5× ULN unless the patient is receiving anticoagulant therapy as long as INR is within the therapeutic range;

⁃ Documented informed consent.