title: The elevated C-reactive protein level is associated with poor prognosis in prostate cancer patients treated with radiotherapy.
abstract: BACKGROUND
  C-reactive protein (CRP) is a sensitive marker of inflammation that has been linked with prognosis in various solid tumours. In the present study, we analysed the prognostic relevance of elevated plasma CRP levels in prostate cancer patients treated with radiotherapy.
  
  
  METHODS
  A total of 261 prostate cancer patients treated with 3D-conformal radiotherapy were evaluated retrospectively. Cancer specific survival (CSS), overall survival (OS) and clinical disease-free survival (DFS) were assessed using Kaplan-Meier analysis. To evaluate the independent prognostic significance of CRP plasma levels, multivariate Cox regression models were applied.
  
  
  RESULTS
  The median follow-time was 80months. Applying receiver operating characteristics (ROC) analysis, the optimal cut-off level for the plasma CRP was 8.6mgl(-1). An elevated CRP level was associated with decreased CSS in univariate (hazard ratio (HR) 3.36, 95% confidence interval (CI) 1.42-7.91; p=0.006) and multivariate analysis (HR 4.31, 95% CI 1.22-15.1; p=0.023). Furthermore, a significant association with OS was detected in univariate (HR 2.69, 95% CI 1.57-4.59; p<0.001) and multivariate analyses (HR 3.24, 95% CI 1.84-5.71, p<0.001). Multivariate analysis also showed a significant association between plasma CRP and clinical DFS (HR 2.07, 95% CI 1.02-4.17; p=0.043).
  
  
  CONCLUSIONS
  In the present study, an elevated plasma CRP (⩾8.6mgl(-1)) has been identified as a prognostic factor for poor CSS, OS and DFS in prostate cancer patients undergoing radiotherapy. The association between elevated CRP levels and poor prognosis was independent of other measures of prognosis such as tumour stage, Gleason grading and prostate specific antigen (PSA) level at diagnosis. If confirmed by additional studies, our findings may contribute to future individual risk assessment in prostate cancer patients.
authors.affiliation: Department of Therapeutic Radiology and Oncology, Medical University of Graz, Austria.
authors.forename: Eva-Maria
authors.initials: EM
authors.lastname: Thurner
authors.affiliation: Department of Therapeutic Radiology and Oncology, Medical University of Graz, Austria.
authors.forename: Sabine
authors.initials: S
authors.lastname: Krenn-Pilko
authors.affiliation: Division of Internal Medicine, Outpatient Department Graz, Austria.
authors.forename: Uwe
authors.initials: U
authors.lastname: Langsenlehner
authors.affiliation: Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Austria.
authors.forename: Tatjana
authors.initials: T
authors.lastname: Stojakovic
authors.affiliation: Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, TX, USA.
authors.forename: Martin
authors.initials: M
authors.lastname: Pichler
authors.affiliation: Division of Clinical Oncology, Department of Internal Medicine, Medical University of Graz, Austria.
authors.forename: Armin
authors.initials: A
authors.lastname: Gerger
authors.affiliation: Department of Therapeutic Radiology and Oncology, Medical University of Graz, Austria.
authors.forename: Karin S
authors.initials: KS
authors.lastname: Kapp
authors.affiliation: Department of Therapeutic Radiology and Oncology, Medical University of Graz, Austria. Electronic address: tanja.langsenlehner@medunigraz.at.
authors.forename: Tanja
authors.initials: T
authors.lastname: Langsenlehner
mesh_terms: D000368:Aged; D019540:Area Under Curve; D014408:Biomarkers, Tumor / Q000097:blood*; D002097:C-Reactive Protein / Q000378:metabolism*; D018450:Disease Progression; D018572:Disease-Free Survival; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D011471:Prostatic Neoplasms / Q000097:blood / Q000401:mortality / Q000532:radiotherapy*; D012372:ROC Curve; D020266:Radiotherapy, Conformal / Q000009:adverse effects* / Q000401:mortality; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D015854:Up-Regulation
chemical_list: D014408:Biomarkers, Tumor; D002097:C-Reactive Protein
keywords: C-reactive protein; Inflammation; Prognosis; Prostate cancer; Radiotherapy