Prognostic Significance of Hematological Markers for Patients with Nasopharyngeal Carcinoma: A Meta-analysis

Purpose: Hematological parameters are considered to be associated with prognosis in various cancers. We designed a meta-analysis to evaluate the prognostic significance of hematological parameters, including the neutrophil-to-lymphocyte ratio (NLR), C-reactive protein/albumin ratio (CRP/ALB), lymphocyte-to-monocyte ratio (LMR), plasma fibrinogen level, Glasgow prognostic score (GPS), platelet-to-lymphocyte ratio (PLR) and high-density lipoprotein cholesterol (HDL-C) level, on clinical outcomes in nasopharyngeal carcinoma (NPC). Methods: Relevant studies published prior to February 2018 were identified in the PubMed, Web of Science, EMBASE and Cochrane library databases. The primary outcome was overall survival (OS), and the secondary outcome was progression-free survival (PFS). The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated. Results: In total, 23 studies encompassing 23,417 patients were included in our meta-analysis. An elevated NLR was related to a poor OS (HR=1.46, 95% CI=1.30-1.63, p<0.00001) and PFS (HR=1.67, 95% CI=1.36-2.07, p<0.00001), and a high PLR was associated with a poor OS (HR=1.62, 95% CI=1.32-1.98, p<0.00001). Additionally, a high LMR predicted a significantly favorable OS (HR=0.50, 95% CI: 0.43-0.58, p<0.00001). CRP/ALB, the GPS, HDL-C and plasma fibrinogen levels were also related to OS and PFS. Conclusion: Inflammation-based prognostic scoring systems considering inflammatory cells (lymphocytes, neutrophils, platelets and monocytes) and proteins (ALB, CRP and HDL-C) are essential prognostic factors.