[Strategies for the prevention and treatment of peritoneal metastases in large Borrmann type III and type IV gastric cancer].

Large Borrmann type III (with maximum tumor diameter ≥8 cm) and Borrmann type IV gastric cancers typically show diffuse infiltration with ill-defined borders and a high frequency of serosal invasion and positive peritoneal lavage cytology, resulting in a high risk of postoperative peritoneal recurrence. Current clinical strategies focus on preventing peritoneal metastasis or recurrence, emphasizing the optimization of perioperative systemic therapy based on precise stratification through staging laparoscopy combined with peritoneal lavage cytology, and exploring the rational combination of triple-drug chemotherapy with immunotherapy and molecular targeted therapy, as well as the screening of suitable populations. Intraperitoneal regional therapy is still in the evidence accumulation phase, requiring combination with standardized surgery and perioperative management, and high-quality prospective studies should be conducted to validate outcomes related to peritoneal recurrence. This article reviews the progress in the prevention and treatment of peritoneal metastasis in large Borrmann type III (with maximum tumor diameter ≥8 cm) and type IV gastric cancer, providing references for clinical decision-making and research design.