Sintilimab Combined With Chemotherapy as Adjuvant Treatment for Phase III GC and GEJ

This study is a prospective, single-arm, phase II clinical study. Screening patients with stage III GC/GEJ adenocarcinoma after D2 or broader radical resection that meets the criteria for group entry and does not meet the exclusion criteria. After signing the informed consent, the subjects entered the trial group to receive adjuvant treatment with Sintilimab combined with chemotherapy (SOX or XELOX ), in which SOX or XELOX chemotherapy was up to 8 cycles, and the total course of treatment was 16 cycles. The efficacy is evaluated every 4 cycles during the study treatment. The frequency of follow-up after treatment is defined as: once every 3 months within 2 years after surgery, every 6 months for 2 to 5 years, and once a year after 5 years. The follow-up interval can be adjusted according to the clinical need. Safety follow-up is from the beginning of the first treatment to 30 days after the last medication.

Inclusion criteria

• Age ≥18.
• Patients with histopathological confirmed gastric/GEJ adenocarcinoma.
• The pTNM is confirmed between IIIA-IIIC and the PD-L1 CPS>=1.
• Patients treated with D2 surgery.
• ECOG is 0 or 1.
• Patients who could tolerate chemotherapy combined with immunotherapy.
• Patients who are not pregnant and have no willing to get pregnant within 6 months after the treatment is over.
• Patients who are willing to offer their postoperative tumor tissue and their peripheral blood samples.
• Patients who are volunteer to sign the ICF.

Exclusion criteria

• Patients who had received neoadjuvent treatments before surgery.
• Patients who have discovered tumor relapse or metastasis before adjuvent treatment.
• Patients who have other malignant tumors.
• Patients who could not swallow the tablets and capsules.
• Other conditions which the researchers think are not suitable for participate the study.