Laparoscopic exploration is vital for detecting occult peritoneal metastasis (opm) in gastric cancer, significantly impacting patient outcomes.

• 22.2% of 653 patients showed opm+ initially, linked to worse survival (15.9 months vs not reached).
• Younger age, better ECOG status, primary gastric cancers, and specific CA72-4 levels were risk factors for opm+.
• Re-evaluating opm status post-treatment revealed changes in 26.4% of patients, influencing survival rates.

Identifying opm early can guide treatment decisions and improve prognoses.