This study is aimed to evaluate the efficacy and safety of sintilimab combined with chemotherapy versus chemotherapy in perioperative treatment of locally advanced esophageal squamous cell carcinoma.

This study was designed as an open-label, randomized controlled, phase II trial. Subjects will be systematically randomized at a ratio of 1:1 and will be assigned to either the experimental group (sintilimab combined with chemotherapy group) or the control group (chemotherapy alone group). They will receive 2-3 cycles of neoadjuvant therapy followed by radical esophagectomy and lymph node dissection and adjuvant therapy determined by investigators. The primary endpoint is 1-year Event-free survival (EFS) rate.

Inclusion Criteria:

• Esophageal squamous cell carcinoma suggested by gastroscopic histopathology.
• The primary tumor is located in the middle and lower of the esophagus.
• cT2-4aN0～3M0 or cT1N+M0 diagnosed by enhanced CT/MRI scan.
• Tumor was evaluated as resectable by surgeon before neoadjuvant therapy.
• Eastern cooperative oncology group (ECOG) performance status of 0 to 1.
• Can eat semi-liquid food.
• Less than 20% body weight loss within 6 months prior to enrollment.
• Sign the consent form before treatment and be able to comply with the relevant procedures such as treatment and visits stipulated in the protocol.
• With adequate organs function 1 week before enrollment and tolerable to chemotherapy and surgery.
• Female subjects of childbearing age or male subjects whose sexual partners are females of childbearing age should take effective contraceptive measures throughout the treatment period and 180 days after the last dose of the test drug.
• Agree and be able to provide archived or fresh pathological tissue and whole blood, urine and fecal samples for biomarker testing.

Exclusion Criteria:

• With metastases or unresectable primary lesion suggested by imaging before treatment.
• History of previous subtotal gastrectomy.
• Patients with active malignancy within 2 years other than the tumor studied in this study or a localized tumor that has been cured such as resected basal or squamous cell carcinoma, superficial bladder cancer, cervical carcinoma in situ, or breast cancer.
• Received any anti-tumor therapy for the research disease in the past, including radiotherapy, chemotherapy, immunotherapy (including but not limited to interleukin, interferon, thymus hormone) and traditional Chinese medicine therapy.
• With signs of pre-esophageal perforation. With any active autoimmune disease or has a history of autoimmune disease.