The regimen of neoadjuvant chemotherapy is nab-paclitaxel (130mg/m2 of BSA, intravenously day 1), oxaliplatin (70mg/m2 of BSA, intravenously day 1) and S-1 (40~60 mg orally twice a day, days 1-8), which will be administered biweekly for six cycles. A comprehensive evaluation, including chest, abdominal and pelvic CT, ultrasonography of cervical lymph nodes and supraclavicular lymph nodes, endoscopy and endoscopic ultrasound, will be performed every 3 cycles. If patients respond to chemotherapy, then they will receive 2 cycles of PD-1 antibody every 3 weeks. Surgery will be performed approximately 8-12 weeks after the last dosage of PD-1 antibody. Postoperatively, immunotherapy or chemotherapy will be administered as adjuvant therapy depending on the degrees of surgical radicality and the pathological reactions of tumors. For patients who have no response to neoadjuvant chemotherapy, surgery, radiation or another systemic regimen will be optioned.
This is a single-institution, prospective phase II trial designed to evaluate the efficacy of neoadjuvant chemotherapy and sequential immunotherapy in patients with locally advanced esophagogastric junction and gastric adenocarcinoma. Patients with Her-2 positive or dMMR tumors will be excluded from the study. Six cycles of nab-paclitaxel, combined with oxaliplatin and S-1, followed by two cycles of PD-1 monoclonal antibody, will be administered as neoadjuvant therapy. Patients will receive different adjuvant treatments depending on the degrees of surgical radicality and the pathological reactions of tumors.