Emerging treatment paradigms for gastric cancer peritoneal metastasis in the era of multimodal precision therapy.

Gastric cancer peritoneal metastasis (GCPM) is usually diagnosed when the disease has already reached a progressive or advanced stage and is associated with a distinctly poor prognosis. Because early detection is difficult and the benefit of conventional systemic therapy remains limited, GCPM has long been regarded as a difficult-to-treat subtype in routine clinical practice. In recent years, advances in molecular classification have driven the exploration of individualised multimodal treatment strategies, with systemic approaches such as immune checkpoint inhibitors, molecularly targeted agents and cellular therapies increasingly incorporated into the management of advanced gastric cancer and GCPM. In parallel, regional intraperitoneal modalities, including hyperthermic intraperitoneal chemotherapy and neoadjuvant intraperitoneal plus systemic chemotherapy, have demonstrated potential benefit in selected patients. On this basis, the present review synthesises up-to-date evidence from major guidelines, expert consensus statements and landmark clinical trials, provides a structured overview of key advances in systemic and regional treatment for GCPM, examines the characteristics of patients who derive benefit and the inherent limitations of current approaches, and discusses future directions for achieving synergy between systemic and regional therapies to prolong survival and improve clinical outcomes.