Neoadjuvant Immunotherapy and Chemotherapy for Locally Advanced Esophagogastric Junction and Gastric Cancer Trial

For locally advanced esophagogastric junction and gastric cancer (cT3-4aNxM0 or cT2N+M0), neoadjuvant chemotherapy can downstage T and N stage,treated distant micrometastases early before local therapy has begun, and finally improve the long-term survival. Combination of perioperative PD-1 antibody and chemotherapy for locally advanced esophagogastric junction and gastric cancer could be a novel therapy to increase response rate and reduce recurrence rate. JS001 in this study is a Chinese anti-PD-1 monoclonal antibody for injection which has been approved for melanoma. This study is a multi-center, open-label, randomized phase II clinical trial to evaluate safety and efficacy of JS001 in combination with perioperative chemotherapy in locally advanced esophagogastric junction and gastric cancer. Differences in gut microbiome and tumor immune microenvironment were detected to screen people who were more sensitive to immunotherapy.