High pretreatment serum C-reactive protein level predicts a poor prognosis for combined small-cell lung cancer.

High serum C-reactive protein (CRP) level is related to poor prognosis in several tumors. The aim of this study was to explore the prognosis value of serum CRP in patients with combined small-cell lung cancer (C-SCLC). The clinicopathological parameters of 112 C-SCLC patients from January 2000 to March 2009 were collected. The pretreatment serum CRP level was measured at diagnosis, and the correlation between serum CRP and clinicopathological characters was analyzed. Univariate and multivariate analyses were performed to investigate the prognostic significance of these parameters for C-SCLC. The pretreatment serum CRP level was elevated in 52.7% of patients (E-CRP; n = 59), while (47.3%) within the normal range (N-CRP; n = 53). There was a significantly worse disease stage (p = 0.037) and higher neuronal specific enolase (NSE) level (p = 0.014) in the E-CRP group. The median overall survival (OS) was significantly longer in the N-CRP group than in the E-CRP group (22.0 vs. 11.5 months, respectively; p < 0.001). Multivariate analyses indicated serum CRP (hazard ratio (HR) = 2.1; p < 0.001), the extent of disease (HR = 1.3; p = 0.039), performance status (HR = 1.8; p = 0.012), and NSE (HR = 1.2; p < 0.001) as independent prognostic factors. High pretreatment serum CRP level predicts a poor long-term prognosis for C-SCLC, which should be considered in defining the prognosis with other prognosticators in C-SCLC patients.