Optimizing Gastric Cancer Treatment: The Role of LODDs in Lymph Node Staging

BackgroundGastric cancer is one of the most common malignancies worldwide and is associated with poor prognosis, placing a considerable burden on public health. Overall treatment outcomes remain unsatisfactory, and accurate lymph node staging is essential for optimizing therapeutic strategies and improving survival. This study aimed to compare the prognostic value of different lymph node staging systems in patients with gastric adenocarcinoma and to provide a more refined prognostic assessment tool for clinical practice. MethodsWe included 4,054 patients with gastric adenocarcinoma from the SEER database (2015-2019) and 383 patients from the First Affiliated Hospital of Hainan Medical University. All patients underwent gastrectomy with D2 lymphadenectomy. Clinicopathological variables included sex, age, race, tumor size, T stage, AJCC N stage (AJCC-N), lymph node ratio (LNR), and log odds of positive lymph nodes (LODDs). Between-group comparisons were performed using the chi-square test. Optimal cut-off values were determined with X-tile software. Survival differences were evaluated by Kaplan-Meier curves. Receiver operating characteristic (ROC) curves were used to compare predictive performance. Cox regression models were applied to identify independent prognostic factors, which were then incorporated into a nomogram. Model performance was assessed using calibration curves and decision curve analysis (DCA). ResultsAJCC-N, LNR and LODDs were strongly and positively correlated in all three datasets (P < 0.001). ROC analysis showed that LODDs had slightly larger areas under the curve than LNR and AJCC-N for predicting 1-, 3- and 5-year survival. Multivariable Cox regression confirmed that LODDs, together with sex, age, race, T stage and tumor size, were independent risk factors for overall survival (P < 0.05). The nomogram constructed from these factors showed good agreement between predicted and observed outcomes on calibration curves, and DCA indicated meaningful clinical net benefit across a broad range of threshold probabilities. ConclusionBy integrating the numbers of positive and negative lymph nodes, LODDs more sensitively reflects changes in metastatic tumor burden and showed the best prognostic performance among the evaluated systems for gastric adenocarcinoma. The proposed nomogram may serve as a useful tool for individualized prognostic assessment.