Baseline C-reactive protein level predicts survival of early-stage lung cancer: evidence from a systematic review and meta-analysis

Purpose: The prognostic impact of baseline C-reactive protein (CRP) in non-small-cell lung cancer (NSCLC) is debated. To evaluate this issue, we performed a systematic review and meta-analysis to explore the role of CRP value in predicting early-stage NSCLC survival. Methods: Ten articles on early-stage NSCLC were eligible and included in our study. We performed a random-effects meta-analysis and assessed heterogeneity and publication bias. We pooled hazard ratio (HR) estimates and their 95% confidence intervals (CIs) on mortality for the comparison between the study-specific highest category of CRP level versus the lowest one. Results: In overall analysis, elevated pretreatment CRP values were significantly associated with poor overall survival (HR 1.60, 95% CI 1.30-1.97, p< 0.001, I-2 = 71.9%). Similar results were observed across considered strata. However, higher mortality risk was reported in studies in which CRP was combined with other factors (HR 1.96, 95% CI 1.58-2.45) and in those using a cutoff value of 3 mg/L (HR 1.89, 95% CI 1.52-2.35). Conclusions: Based on our analysis, baseline high CRP level is significantly associated with poor prognosis in early-stage NSCLC. Further prospective controlled studies are needed to confirm these data.