Abstract Introduction Gastric cancer peritoneal metastasis (GCPM) is a common manifestation of advanced gastric cancer, associated with poor prognosis. Methods The International Gastric Cancer Association (IGCA) convened a multidisciplinary working group of 42 global experts from 15 countries to develop a total of thirteen consensus statements addressing diagnosis, treatment, and research priorities for GCPM. Using ACCORD-compliant methodology, the group conducted systematic literature searches and applied a structured Delphi process with anonymous Likert-scale voting and ≥70% consensus threshold to generate and refine consensus statements. Results Consensus was achieved for all thirteen statements among the working group during the first Delphi round with 75-100% of respondents selecting either “Strongly Agree” or “Agree”. Coefficients of variation values were ≤ 0.23. Polling of a broader group of experts (n=63) that included members of the working group (n=21) during the IGCC (2025) GCPM Consensus Session demonstrated agreement for twelve of the thirteen statements. This broader group of experts, that had greater representation from medical oncologists, did not reach consensus (52% agreement) on best practice for systemic treatment of patients with GCPM, possibly due the rapidly evolving developments in this field of metastatic gastric cancer. Conclusion This consensus exercise provides a foundation for globally relevant GCPM management strategies and highlights critical research needed to address significant evidence gaps that will improve patient outcomes.
Boshier et al. (2026) studied this question.