Current Challenges and Future Directions in the Multimodal Management of Gastric Cancer with Peritoneal Metastases

Peritoneal metastases represent one of the most dreadful manifestations of gastric cancer and continue to drive poor outcomes despite significant advances in systemic therapy. Accurate staging-beginning with laparoscopy-remains essential for avoiding non-beneficial surgery and ensuring appropriate allocation to systemic or locoregional treatment pathways. Although modern systemic agents, including immunotherapy and targeted therapies, have transformed the broader management of metastatic disease, their impact in the peritoneal compartment remains limited, reflecting its unique biological and pharmacokinetic constraints. Locoregional approaches such as CRS-HIPEC, PIPAC, and NIPS have expanded the therapeutic armamentarium and have shown encouraging signals in selected populations. Recent randomized studies, including ESTOK01 and PERISCOPE II, emphasize the importance of careful patient selection, technical standardization, and optimal sequencing, while ongoing trials-such as PREVENT, GASTRICHIP, and CONVERGENCE-seek to refine the integration of systemic and intraperitoneal strategies. Yet the field continues to advance without the benefit of validated predictive biomarkers capable of guiding therapeutic decisions. This limitation constrains clinical progress and underscores the need for a stronger translational framework. Future improvement in the management of gastric cancer with peritoneal metastases will depend on the identification of robust biological predictors of response, enabling more rational patient selection and the development of truly personalized multimodal approaches.