Crucially, the model is exclusively applicable to elderly gastric cancer patients meeting this study’s inclusion criteria: those undergoing radical surgery without other malignancies or severe organ dysfunction (e.g., severe heart/liver/kidney failure), with complete preoperative NLR and tumor-specific data (including verified tumor size, lymph node metastasis status, and CEA levels). This evidence concerns the gene CEACAM5 and metastatic malignant neoplasm in the lymph nodes.