Prognostic impact of preoperative immunenutritional indices in patients undergoing curative resection for non-small cell lung cancer: a retrospective analysis.

BACKGROUND: The prognostic significance of the neutrophil-to-lymphocyte ratio (NLR) in non-small cell lung cancer (NSCLC) has been widely reported; however, its utility in predicting recurrence after complete resection, particularly in early-stage disease, remains unclear. This study aimed to evaluate the prognostic value of preoperative NLR and compare it with other immunonutritional indices. METHODS: We retrospectively analyzed 789 patients who underwent complete resection for NSCLC between 2012 and 2022. Patients with infection, inflammatory disease, neoadjuvant therapy, or incomplete data were excluded. Recurrence-free survival (RFS) was assessed in the overall cohort (Cohort 1) and in patients with pathological stage I disease (Cohort 2). Optimal cutoff values for NLR, prognostic nutritional index (PNI), geriatric nutritional risk index (GNRI), and controlling nutritional status (CONUT) score were determined using receiver operating characteristic analysis. Cox proportional hazards models were used to identify predictors of recurrence. RESULTS: Recurrence occurred in 22.6% of patients. High preoperative NLR was significantly associated with poorer RFS in both Cohort 1 (5-year RFS: 67.8% vs. 80.3%, P<0.001) and Cohort 2 (75.6% vs. 87.8%, P<0.001). In multivariable analysis, NLR was not an independent predictor in the overall cohort (P=0.07), whereas it remained independently associated with recurrence in stage I patients (hazard ratio 1.67, 95% confidence interval: 1.05-2.64; P=0.03). Among immunonutritional indices, NLR demonstrated superior discriminatory ability for recurrence compared with PNI, GNRI, and CONUT score in stage I disease. CONCLUSIONS: Preoperative NLR is a simple and clinically useful biomarker for predicting postoperative recurrence in patients with completely resected stage I NSCLC. Its prognostic value appears limited in the overall population but remains significant in early-stage disease. Incorporating NLR into perioperative risk stratification may improve identification of high-risk patients and guide postoperative surveillance strategies. Further prospective validation is warranted.