The combination of pretreatment prognostic nutritional index and neuron-specific enolase enhances prognosis predicting value of small cell lung cancer.

Background: Tumor and immune-inflammatory biomarkers have been demonstrated to be closely associated with cancer prognosis.

Objective: The present study aims to assess the prognostic value of pretreatment prognostic nutritional index (PNI), carcinoembryonic antigen (CEA), and neuron-specific enolase (NSE) in small cell lung cancer (SCLC).

Methods: A retrospective analysis of 301 SCLC patients treated with platinum-based chemotherapy was performed. Overall survival (OS) was assessed by Kaplan-Meier and multivariate Cox hazard analyses.

Results: The median OS for total cases was 15.0 months. On univariate analysis, tumor stage (P < 0.001), pretreatment PNI (P < 0.001), CEA (P = 0.039), NSE (P = 0.010), distant metastasis numbers (P < 0.001), and thoracic radiotherapy (P < 0.001) were found to be the predictors of OS. Multivariate analysis showed limited stage, high PNI, NSE < 15 μg/L, and chemoradiotherapy were positive independent prognostic factors (P < 0.05). Low PNI and NSE ≥ 15 μg/L were closely correlated with a high tumor burden status. Three cohorts of SCLC with significant different survival outcomes were divided based on variable PNI and NSE levels. Patients with high PNI and NSE < 15 μg/L showed the best OS of 24.5 months, while patients with low PNI and NSE ≥ 15 μg/L had the worst survival outcome of 10.0 months. Patients with low PNI and NSE < 15 μg/L or high PNI and NSE ≥ 15 μg/L had the similar outcome of 16.5 and 17.0 months, respectively.

Conclusions: Pretreatment PNI and NSE were independent prognostic factors of SCLC. The combination of PNI and NSE enhanced the OS predicting ability, and patients with high PNI and NSE < 15 μg/L had the best survival outcome.