title: Pretreatment hematologic markers as prognostic factors in patients with nasopharyngeal carcinoma: A systematic review and meta-analysis.
abstract: BACKGROUND
  Pretreatment hematologic parameters of the inflammatory response, including lymphocyte, neutrophil, and platelet counts, neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio, and platelet-to-lymphocyte ratio, have emerged as prognostic factors for patients with cancer. This systematic review and meta-analysis aimed to summarize the association between the hematologic markers and prognosis of nasopharyngeal carcinoma (NPC).
  
  
  METHODS
  A systematic search of PubMed, Google Scholar, MEDLINE, EMBASE, Web of Science, and the Cochrane Library was conducted up to April 2016. Hazard ratios (HRs) with 95% confidence intervals (95% CIs) were extracted and synthesized to examine prognostic outcomes including cancer-specific survival (CSS), overall survival (OS), progression-free survival (PFS), distant metastasis-free survival, and local relapse-free survival (LRFS).
  
  
  RESULTS
  Fourteen studies comprising 11,651 NPC patients were ultimately included, and all eligible studies were conducted in East Asia. The OS, CSS, PFS, distant metastasis-free survival, and LRFS risks differed among patients according to hematologic marker levels. All of the parameters were associated with prognostic outcomes in patients with NPC. NLR and lymphocyte counts were most commonly reported. A high NLR was significantly associated with poor NPC prognosis (pooled HR 1.42, 95% CI 1.21-1.67 for CSS; pooled HR 1.77, 95% CI 1.41-2.23 for OS; pooled HR 1.67, 95% CI 1.36-2.06 for PFS; pooled HR 1.64, 95% CI 1.15-2.34 for LRFS). High lymphocyte count indicated favorable NPC prognosis (pooled HR 0.72, 95% CI 0.64-0.81 for OS; pooled HR 0.71, 95% CI 0.56-0.91 for PFS).
  
  
  CONCLUSIONS
  Meta-analysis indicated that NLR and lymphocyte counts could be prognostic predictors in NPC for East Asian population. Patients with a high NLR or low lymphocyte count had poor prognosis. However, due to the limitation of included population, the conclusion was limited to East Asian patients only.
authors.affiliation: Department of Radiation Oncology, First Affiliated Hospital of Fujian Medical University Key Laboratory of Radiation Biology (Fujian Medical University), Fujian Province University Fujian Key Laboratory of Individualized Active Immunotherapy, Fujian Medical University, Fuzhou, Fujian, China.
authors.forename: Li
authors.initials: L
authors.lastname: Su
authors.forename: Mingwei
authors.initials: M
authors.lastname: Zhang
authors.forename: Weijian
authors.initials: W
authors.lastname: Zhang
authors.forename: Chuanshu
authors.initials: C
authors.lastname: Cai
authors.forename: Jinsheng
authors.initials: J
authors.lastname: Hong
mesh_terms: D044466:Asian People; D014408:Biomarkers, Tumor; D002277:Carcinoma; D006403:Hematologic Tests / Q000706:statistics & numerical data*; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood* / Q000378:metabolism; D018655:Lymphocyte Count; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000097:blood* / Q000401:mortality / Q000473:pathology*; D009364:Neoplasm Recurrence, Local; D009504:Neutrophils / Q000378:metabolism; D011379:Prognosis; D016016:Proportional Hazards Models; D016019:Survival Analysis
chemical_list: D014408:Biomarkers, Tumor; D018836:Inflammation Mediators