Background: The aim was to determine the prognostic value of the neutrophil-lymphocyte ratio (NLR) in patients with completely resected stage 1 non-small cell lung cancer (NSCLC).
Methods: The study enrolled 382 NSCLC patients, and an optimal NLR cutoff value was determined by ROC analysis. Patients were divided by preoperative NLR into low (< 1.5, n = 99), intermediate (1.5 ≤ NLR < 3.5, n = 245), and high (NLR ≥ 3.5, n = 38) value groups. Serum diacron-reactive oxygen metabolites (d-ROMs) were assayed in 33 consecutive patients and used as an indicator of oxidative stress.
Results: The mean NLR in patients with high d-ROMs (> 300 U.CARR, n = 16) was 1.72 ± 0.67, which was significantly higher than that in patients with low d-ROMs (1.41 ± 0.39, n = 17; P = 0.018). The 3-, 5- and 10-year survival rates in the three NLR groups were 92, 77, and 59% (low); 82, 70, and 50% (intermediate); and 76, 58, and 32% (high) (P = 0.034). The 1-, 3- and 5-year recurrence-free survival rates in the three groups were 98, 90, and 86% (low), 91, 77, and 74% (intermediate); and 92, 77, and 68% (high) (P = 0.033). Multivariate analysis found that although NLR was not predictive of overall survival, high NLR was an independent risk factor of recurrence (hazard ratio: 2.03, 95% confidence interval: 1.17-3.79, P = 0.011) as were as age, pathological stage, tumor differentiation, and lymph-vascular invasion.
Conclusions: A low preoperative NLR predicted good prognosis, and was associated with low systemic inflammation status in patients with stage 1 NSCLC. It may be helpful when considering intervals of routine follow-up or choice of adjuvant therapy.
Keywords: Neutrophil-lymphocyte ratio; Non-small cell lung cancer; Prognosis; Recurrence-free survival; Surgery.