Prognostic performance of inflammation-based prognostic indices in primary operable non-small cell lung cancer

Background: At least 30% of patients with primary resectable non-small cell lung cancer (NSCLC) will experience a relapse in their disease within 5 years following definitive treatment. Clinicopathological predictors have proved to be suboptimal in identifying high-risk patients. We aimed to establish whether inflammation-based scores offer an improved prognostic ability in terms of estimating overall (OS) and recurrence-free survival (RFS) in a cohort of operable, early-stage NSCLC patients. Methods: Clinicopathological, demographic and treatment data were collected prospectively for 220 patients operated for primary NSCLC at the Hammersmith Hospital from 2004 to 2011. Pretreatment modified Glasgow Prognostic Score (mGPS), neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were tested together with established prognostic factors in uni- and multivariate Cox regression analyses of OS and RFS. Results: Half of the patients were male, with a median age of 65. A total of 57% were classified as stage I with adenocarcinoma being the most prevalent subtype (60%). Univariate analyses of survival revealed stage (P<0.001), grade (P=0.02), lymphovascular (LVI, P=0.001), visceral pleural invasion (VPI, P=0.003), mGPS (P=0.02) and NLR (P=0.04) as predictors of OS, with stage (P<0.001), VPI (P=0.02) and NLR (P=0.002) being confirmed as independent prognostic factors on multivariate analyses. Patients with more advanced stage (P<0.001) and LVI (P=0.008) had significantly shorter RFS. Conclusions: An elevated NLR identifies operable NSCLC patients with a poor prognostic outlook and an OS difference of almost 2 years compared to those with a normal score at diagnosis. Our study validates the clinical utility of the NLR in early-stage NSCLC.