Comparison of the Effectiveness of Laboratory Parameters in Predicting Lymph Node Positivity in Patients with Gastric Cancer

Abs tractAim: We proposed that inflammation and nutrition-based laboratory indices measured at the time of initial diagnosis could predict lymph node positivity in patients with gastric adenocarcinoma.In this context, this study aimed to evaluate and compare the predictive performance of the C-reactive protein (CRP) -to-albumin ratio (CAR), CRP-to-lactate dehydrogenase ratio (CLDR), lymphocyte-to-CRP ratio (LCR), and CRP-albumin-lymphocyte index (CALLY).Methods: This retrospective, single-center observational study included 215 consecutive patients who underwent gastrectomy for histologically confirmed gastric adenocarcinoma between January 2014 and May 2024.Preoperative laboratory parameters were used to calculate CAR, CLDR, LCR, and CALLY.Receiver operating characteristic (ROC) curve analysis assessed discriminative ability, and multivariable logistic regression was performed to identify independent predictors of lymph node positivity, adjusting for age, sex, and neoadjuvant therapy status.Results: Lymph node metastasis was present in 173 patients (80%).CAR and CLDR were significantly higher in patients with nodal involvement (p=0.014 and p=0.017, respectively), whereas LCR and CALLY showed borderline associations (p=0.056 and p=0.052).ROC analysis revealed modest predictive ability, with area under the curve values of 0.622 for CAR and 0.618 for CLDR.In multivariable analysis, both CAR [odds ratio (OR): 1.36, p=0.026] and CLDR (OR: 19.93, p=0.018) remained independent predictors of lymph node positivity. Conclusion:CAR and CLDR are inexpensive and widely accessible indices that independently predict lymph node metastasis in gastric cancer at diagnosis.Although their discriminative performance is modest, they may provide complementary value when combined with imaging and clinicopathological data to improve preoperative risk stratification.