title: Prognostic significance of neutrophil to lymphocyte ratio in pancreatic cancer: a meta-analysis.
abstract: OBJECTIVE
  To conduct a meta-analysis evaluating the association between the peripheral blood neutrophil to lymphocyte ratio (NLR) and the outcome of patients with pancreatic cancer.
  
  
  METHODS
  Studies evaluating the relationship between the peripheral blood NLR and outcome of patients with pancreatic cancer published up to May 2014 were searched using electronic databases, including PubMed, Web of Science, Embase and Ovid. A meta-analysis was performed to pool the hazard ratios (HRs) or odds ratios (ORs) and their 95% confidence intervals (CIs) using either a fixed-effects model or a random-effects model to quantitatively assess the prognostic value of NLR and its association with clinicopathological parameters.
  
  
  RESULTS
  Eleven studies containing a total of 1804 patients were eligible according to our selection criteria, and combined hazard ratios indicated that high NLR was a poor prognostic marker for pancreatic cancer patients because it had an unfavorable impact on the overall survival (OS) (HR = 2.61, 95%CI: 1.68-4.06, P = 0.000) and cancer specific survival (HR = 1.66, 95%CI: 1.08-2.57, P = 0.021). Subgroup analysis revealed that high NLR was associated with poor OS in patients with mixed treatment (HR = 4.36, 95%CI: 2.50-7.61, P = 0.000), chemotherapy (HR = 2.08, 95%CI: 1.49-2.9, P = 0.000), or surgical resection (HR = 1.2, 95%CI: 1.00-1.44, P = 0.048). Additionally, high NLR was significantly correlated with tumor metastasis (OR = 1.69, 95%CI: 1.10-2.59, P = 0.016), poor tumor differentiation (OR = 2.75, 95%CI: 1.19-6.36, P = 0.016), poor performance status (OR = 2.56, 95%CI: 1.63-4.03, P = 0.000), high cancer antigen 199 (OR = 2.62, 95%CI: 1.49-4.60, P = 0.000), high C-reactive protein (OR = 4.32, 95%CI: 2.71-6.87, P = 0.000), and low albumin (OR = 3.56, 95%CI: 1.37-9.27, P = 0.009).
  
  
  CONCLUSIONS
  High peripheral blood NLR suggested a poor prognosis for patients with pancreatic cancer, and it could be a novel marker of survival evaluation and could help clinicians develop therapeutic strategies for pancreatic cancer patients.
authors.affiliation: Jian-Jun Yang, Zhi-Gao Hu, Song-Qing He, Sheng-Guang Yuan, Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin 541001, Guangxi Zhuang Autonomous Region, China.
authors.forename: Jian-Jun
authors.initials: JJ
authors.lastname: Yang
authors.affiliation: Jian-Jun Yang, Zhi-Gao Hu, Song-Qing He, Sheng-Guang Yuan, Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin 541001, Guangxi Zhuang Autonomous Region, China.
authors.forename: Zhi-Gao
authors.initials: ZG
authors.lastname: Hu
authors.affiliation: Jian-Jun Yang, Zhi-Gao Hu, Song-Qing He, Sheng-Guang Yuan, Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin 541001, Guangxi Zhuang Autonomous Region, China.
authors.forename: Wu-Xiang
authors.initials: WX
authors.lastname: Shi
authors.affiliation: Jian-Jun Yang, Zhi-Gao Hu, Song-Qing He, Sheng-Guang Yuan, Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin 541001, Guangxi Zhuang Autonomous Region, China.
authors.forename: Te
authors.initials: T
authors.lastname: Deng
authors.affiliation: Jian-Jun Yang, Zhi-Gao Hu, Song-Qing He, Sheng-Guang Yuan, Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin 541001, Guangxi Zhuang Autonomous Region, China.
authors.forename: Song-Qing
authors.initials: SQ
authors.lastname: He
authors.affiliation: Jian-Jun Yang, Zhi-Gao Hu, Song-Qing He, Sheng-Guang Yuan, Laboratory of Hepatobiliary and Pancreatic Surgery, Affiliated Hospital of Guilin Medical University, Guilin 541001, Guangxi Zhuang Autonomous Region, China.
authors.forename: Sheng-Guang
authors.initials: SG
authors.lastname: Yuan
mesh_terms: D006801:Humans; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000276:immunology*; D009504:Neutrophils / Q000276:immunology*; D016017:Odds Ratio; D010190:Pancreatic Neoplasms / Q000276:immunology* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D011237:Predictive Value of Tests; D012307:Risk Factors; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome
keywords: Cancer specific survival; Clinicopathological features; Meta-analysis; Neutrophil to lymphocyte ratio; Overall survival; Pancreatic cancer