Effect of Systemic or Intraperitoneal Administration of Anti-PD-1 Antibody for Peritoneal Metastases from Gastric Cancer

PD-1 blockade therapy remodels the cellular immune composition of peritoneal tumors, which can partially suppress the PM from GC regardless of the route of administration. Adding anti-PD-1 antibody to chemotherapeutic regimens may enhance their anti-tumor effects against PM, which can lead to the prolongation of survival of patients with GC with peritoneal involvement.