title: Urinary N-telopeptide (uNTx) is an independent prognostic factor for overall survival in patients with bone metastases from castration-resistant prostate cancer.
abstract: BACKGROUND
  In patients with bone metastases from castration-resistant prostate cancer (CRPC) not pretreated with a bisphosphonate elevated N-telopeptide of type I collagen (uNTx), a marker of bone resorption, predicts skeletal-related events (SRE). The aim of this study was to assess the prognostic value of uNTx for overall survival (OS) and the incidence of SRE in patients with bone metastases from CRPC receiving zoledronic acid.
  
  
  METHODS
  From 2004 to 2007, 94 patients with bone metastases from CRPC receiving zoledronic acid for at least 2 months were screened for uNTx.
  
  
  RESULTS
  Median age was 66 years (range 46-88). Median serum prostate-specific antigen (PSA) was 66 ng/ml (0-3984) and median uNTx was 19 nmol/mM creatinine (3-489). During follow-up, 38 patients (40%) experienced an SRE. Median OS was 20 months [95% (CI) confidence interval 15-24). In the multivariate analysis, elevated uNTx [hazard ratio (HR) 2.2 (95% CI 1.2-4.0)], serum PSA [HR 2.8 (95% CI 1.6-5.1)], and ECOG performance status were the only independent prognostic factors for OS. Median OS was 12 months (10-16) and 25 months (21-34) in patients with uNTx > or =20 nmol/mM creatinine and in those with uNTx <20 nmol/mM creatinine, respectively.
  
  
  CONCLUSIONS
  An elevated uNTx level is an independent prognostic factor for OS in patients with bone metastases from CRPC receiving a bisphosphonate.
authors.affiliation: Department of Medicine.
authors.forename: S
authors.initials: S
authors.lastname: Rajpar
authors.affiliation: Department of Medicine.
authors.forename: C
authors.initials: C
authors.lastname: Massard
authors.affiliation: Department of Biostatistics and Epidemiology.
authors.forename: A
authors.initials: A
authors.lastname: Laplanche
authors.affiliation: Department of Biostatistics and Epidemiology.
authors.forename: E
authors.initials: E
authors.lastname: Tournay
authors.affiliation: Department of Medicine.
authors.forename: M
authors.initials: M
authors.lastname: Gross-Goupil
authors.affiliation: Department of Medicine.
authors.forename: Y
authors.initials: Y
authors.lastname: Loriot
authors.affiliation: Department of Medicine.
authors.forename: M
authors.initials: M
authors.lastname: Di Palma
authors.affiliation: Department of Radiotherapy.
authors.forename: A
authors.initials: A
authors.lastname: Bossi
authors.affiliation: Department of Medicine.
authors.forename: B
authors.initials: B
authors.lastname: Escudier
authors.affiliation: Department of Translational Research Unit, Institut Gustave Roussy, University of Paris XI, Villejuif, France.
authors.forename: A
authors.initials: A
authors.lastname: Chauchereau
authors.affiliation: Department of Medicine. Electronic address: fizazi@igr.fr.
authors.forename: K
authors.initials: K
authors.lastname: Fizazi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000652:urine*; D050071:Bone Density Conservation Agents / Q000627:therapeutic use; D001859:Bone Neoplasms / Q000401:mortality* / Q000556:secondary / Q000652:urine; D002369:Castration; D024042:Collagen Type I / Q000652:urine*; D004164:Diphosphonates / Q000627:therapeutic use; D005500:Follow-Up Studies; D006801:Humans; D007093:Imidazoles / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009376:Neoplasms, Hormone-Dependent / Q000401:mortality* / Q000473:pathology / Q000652:urine; D010455:Peptides / Q000652:urine*; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000401:mortality* / Q000473:pathology / Q000652:urine; D015996:Survival Rate; D016896:Treatment Outcome; D000077211:Zoledronic Acid
chemical_list: D014408:Biomarkers, Tumor; D050071:Bone Density Conservation Agents; D024042:Collagen Type I; D004164:Diphosphonates; D007093:Imidazoles; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D000077211:Zoledronic Acid; D017430:Prostate-Specific Antigen