title: Validation of the neutrophil-to-lymphocyte ratio as a prognostic factor in a cohort of European prostate cancer patients.
abstract: OBJECTIVE
  Recent studies have expanded the concept that the systemic inflammatory response has an important role in the progression of several solid tumors. The neutrophil-to-lymphocyte ratio (NLR), an easily determinable marker of systemic inflammation, has been associated with clinical outcome in various cancer entities. In the present study, we validated the prognostic relevance of an elevated NLR in a cohort of European prostate cancer patients.
  
  
  METHODS
  Data from 415 consecutive prostate cancer patients treated with 3D conformal radiotherapy at a single tertiary academic center from 1999 to 2007 were included in this retrospective study. Clinical progression-free survival (PFS), distant metastases-free survival (DMFS), and overall survival (OS) were assessed using the Kaplan-Meier method. To evaluate the prognostic relevance, univariate and multivariate Cox regression models were performed for each end point.
  
  
  RESULTS
  Based on previously published studies, an NLR ≥ 5 was selected as cutoff value for external validation. Multivariate analysis identified an increased NLR as an independent prognostic factor for clinical PFS [hazard ratio (HR) 3.09, 95 % CI 1.64-5.82, p < 0.001], DMFS (HR 3.51, 95 % CI 1.80-6.85, p < 0.001), and OS (HR 2.16, 95 % CI 1.17-3.99, p = 0.013).
  
  
  CONCLUSIONS
  The NLR seems to represent an independent prognostic marker and should be considered for future individual risk assessment in patients with prostate cancer.
authors.affiliation: Department of Therapeutic Radiology and Oncology, Comprehensive Cancer Center Graz, Medical University of Graz, Auenbruggerplatz 32, 8036, Graz, Austria. tanja.langsenlehner@medunigraz.at.
authors.forename: Tanja
authors.initials: T
authors.lastname: Langsenlehner
authors.affiliation: Department of Therapeutic Radiology and Oncology, Comprehensive Cancer Center Graz, Medical University of Graz, Auenbruggerplatz 32, 8036, Graz, Austria.
authors.forename: Eva-Maria
authors.initials: EM
authors.lastname: Thurner
authors.affiliation: Department of Therapeutic Radiology and Oncology, Comprehensive Cancer Center Graz, Medical University of Graz, Auenbruggerplatz 32, 8036, Graz, Austria.
authors.forename: Sabine
authors.initials: S
authors.lastname: Krenn-Pilko
authors.affiliation: Division of Internal Medicine, Outpatient Department Graz, Graz, Austria.
authors.forename: Uwe
authors.initials: U
authors.lastname: Langsenlehner
authors.affiliation: Clinical Institute of Medical and Chemical Laboratory Diagnostics, Comprehensive Cancer Center Graz, Medical University of Graz, Graz, Austria.
authors.forename: Tatjana
authors.initials: T
authors.lastname: Stojakovic
authors.affiliation: Division of Clinical Oncology, Department of Medicine, Comprehensive Cancer Center, Medical University of Graz, Graz, Austria.
authors.forename: Armin
authors.initials: A
authors.lastname: Gerger
authors.affiliation: Division of Clinical Oncology, Department of Medicine, Comprehensive Cancer Center, Medical University of Graz, Graz, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Pichler
mesh_terms: D000368:Aged; D001317:Austria / Q000453:epidemiology; D018450:Disease Progression; D018572:Disease-Free Survival; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D007958:Leukocyte Count; D008214:Lymphocytes / Q000473:pathology*; D008297:Male; D009504:Neutrophils / Q000473:pathology*; D011379:Prognosis; D016016:Proportional Hazards Models; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000453:epidemiology; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends
keywords: Inflammation; Neutrophil-to-lymphocyte ratio; Prognosis; Prostate cancer