To investigate the risk factors affecting lymph node metastasis of gastric cancer in the elderly and to construct a column-line graph model for predicting the risk of lymph node metastasis of gastric cancer.

The clinicopathological data of 248 primary elderly gastric cancer patients who underwent radical resection for gastric cancer in Shaanxi Provincial People’s Hospital between January 2021 and December 2023 were retrospectively collected. The HALP score was calculated based on preoperative levels of hemoglobin, serum albumin, lymphocyte count, and platelet count. The patients were divided into metastatic group (156 cases) and non-metastatic group (92 cases) according to the presence or absence of lymph node metastasis, and explored the influencing factors of lymph node metastasis of gastric cancer by using single-factor and multifactorial Logistic regression analyses. A prediction model was constructed on the basis of the results of the multifactorial analyses, and then further validated for the differentiation degree, calibration degree, and clinical practicability of the model.

HALP score ≤28.26 (OR=0.425, 95% CI: 0.222-0.812; P=0.010), CA19-9 ≥12.62 (OR=2.860, 95% CI: 1.506-5.432; P=0.001), and the degree of hypo differentiation (OR=0.504, 95% CI: 0.272-0.935; P=0.030), depth of infiltration cT_≥2 (OR=5.278, 95% CI: 2.485-11.206; P<0.001), and history of diabetes mellitus (OR=2.727, 95% CI: 1.082-6.875; P=0.033) were the risk factors affecting lymph node metastasis of gastric cancer. The area under the ROC of the column-line diagram model constructed based on these factors was 0.801 (95% CI: 0.743-0.859); the calibration curve showed that the probability of occurrence of gastric cancer lymph node metastasis predicted by the column-line diagram was in good agreement with the actual results. The decision curve analysis showed that the column-line diagram model could obtain clinical benefits in a wide range of thresholds, which had better practicality.

The prediction model can better assess the risk of gastric cancer lymph node metastasis in elderly patients with a good range of clinical benefits, which can provide reference for clinicians to identify patients with gastric cancer lymph node metastasis before surgery, and help to formulate a more tailored surgical and therapeutic plan to improve the prognosis.