This Prospective, single-arm Phase Ⅱ study is to determine the efficacy and safety of Once-daily Simultaneous Modulated Accelerated Radiotherapy combined with S-1/DDP for geratic esophageal squamous cell carcinoma patients.

Inclusion Criteria:

• Pathologically or cytologically confirmed esophageal squamous cell carcinoma.
• Stage II-IVa ESCC confirmed by endoscopic ultrasonography(EUS) and imaging studies.
• Aging from 70 to 80.
• Eastern Cooperative Oncology Group (ECOG) performance status 0-2.
• Charlson's weighted index of comorbidities (WIC) ≤4；
• White blood cell count ≥4×109 /L, neutrophile granulocyte count≥1.5×109 /L, platelet count≥100×109 /L, hemoglobin ≥100 g /L, serum creatinine and bilirubin 1.5 times less than the upper limits of normal (ULN),aminotransferase two times less than the ULN.
• Weight loss ≤15% within the past half year.
• Forced expiratory volume in 1 s≥ 1 L.
• Patients and their family signed the informed consents.

Exclusion Criteria:

• Previous or recent another malignancy, except for nonmelanoma skin cancer or cervical cancer in situ.
• Already received antineoplastic therapy,including chemotherapy, radiotherapy or operation.
• Any contraindication for chemotherapy or radiotherapy(such as a myocardial infarction within 6 months,immunosuppressive therapy,symptomatic heart disease,including unstable angina pectoris, congestive heart failure,and uncontrolled arrhythmia.)
• Malignant pleural effusion or pericardial effusion.
• Weight loss >10% within the past 3 months.
• Recruited in other clinical trials within 30 days
• Drug addiction, long-term alcohol abuse and AIDS patients.
• Uncontrollable epileptic attack or psychotic patients without self-control ability.
• Severe allergy or idiosyncrasy.
• Not suitable for this study judged by researchers.