The time-series behavior of systemic inflammation-immune status in predicting survival of locally advanced non-small cell lung cancer treated with chemoradiotherapy

Background: Systematic inflammation is believed to play a crucial role in tumorigenesis and metastasis. This study aims at evaluating the prognostic value of time-series behavior of systematic inflammation-immune status before and after definitive chemoradiotherapy (dCRT) in patients with locally advanced non-small cell lung cancer (LA-NSCLC). Methods: The relationship between systematic inflammation-immune score (SIS, defined as pretreatment peripheral platelet count × neutrophil count/lymphocyte count) and the prognosis was tested in a retrospective study of 386 consecutive LA-NSCLC patients (Group A) with pretreatment SIS and 161 patients (Group B) with SIS before and one month after the dCRT. Results: SIS of 1400 × 109 was found to be an optimal cutoff point to stratify the patients into high (>1400 × 109) and low (≤1400 × 109) SIS groups. Univariate and multivariate analyses revealed that the SIS, whether before or after dCRT, was an independent predictor for overall survival (OS), progress-free survival (PFS), and distant metastasis-free survival (DMFS). High SIS (>1400 × 109) was shown to predict poor 3-year OS (P=0.006, hazard ratio [HR]=2.427), PFS (P=0.001, HR=2.442) and DMFS (P=0.015, HR=2.119). However, SIS was not related to local regional recurrence-free survival in either Group A (P=0.346) or Group B (P=0.486). Further, the area under the receiver operating characteristic curve of the SIS for OS was higher than the neutrophil count/lymphocyte count ratio, platelet count/lymphocyte count ratio, and other conventional clinic-pathological indices. Conclusions: The SIS is a stable and more sensitive survival predictor than other inflammation-based factors and conventional clinical indices, which may aid in more accurately stratifying patients for risk assessment and treatment decisions.