Prognostic value of circulating C-reactive protein levels in patients with non-small cell lung cancer: A systematic review with meta-analysis

Background: The clinical and prognostic significance of C-reactive protein (CRP) in nonsmall-cell lung cancer (NSCLC) remains inconsistent. To clarify a precise determinant of the clinical significance of CRP, we conducted a systematic review and meta-analysis to evaluate the overall risk of elevated CRP for survival in NSCLC. Materials and Methods: Related studies were identified and evaluated for quality through multiple search strategies. Data were collected from studies comparing overall survival in patients with elevated CRP levels and those having lower levels. The meta-analysis was performed by Review Manager version 5.2 (RevMan; the Cochrane Collaboration, Oxford, England). The pooled hazard ratios (HRs) and 95% confidence intervals (Cl) were calculated employing fixed- or random-effects models depending on the heterogeneity of the included trials. Results: Eight eligible studies involved 1649 patients were ultimately identified. Combined HRs suggested that elevated CRP had an unfavorable impact on survival of patients with NSCLC. The HRs (95% Cl) was 1.55 (1.19-2.01) overall, 1.78 (1.33-2.38) in Asian patients, 1.33 (1.00-1.77) in non-Asian patients, 1.78 (1.47-2.15) in primary resectable NSCLC, 1.28 (0.95-1.73) in primary unresectable NSCLC, 1.78 (1.33-2.38) in group of cut-off value <5 mg/L, 1.33 (1.00-1.77) in group of cut-off value 10 mg/L. Conclusions: With the available evidence, CRP might serve as an efficient prognostic indicator in NSCLC. This marker should be taken into consideration in the development of new diagnostic and therapeutic program for NSCLC.