Study of Perioperative Chemotherapy Combined With Tislelizumab and Trastuzumab in the Treatment of GC/EGC

tislelizumab (intravenously, 200 mg on day 1 of every cycle for 4 preoperative and 12 postoperative cycles)

Trastuzumab(intravenously, 8 mg/kg loading dose, then 6 mg/kg on days 1 of every cycle for 4 preoperative and 12 postoperative cycles)

docetaxel (intravenously, 50 mg/m2 on day 1 of every cycle for 3 preoperative cycles)

S1 (orally, 400mg/m2 BID on day 1\~14 of every cycle for 3 preoperative and 3 postoperative cycles )

Oxaliplatin(intravenously, 100 mg /m2 on day 1 of every cycle for 3 preoperative cycles ;130mg /m2 on day 1 of every cycle for 3 postoperative cycles.