title: Changes of biochemical markers of bone turnover and YKL-40 following hormonal treatment for metastatic prostate cancer are related to survival.
abstract: OBJECTIVE
  Elevated serum levels of biochemical markers of bone turnover and YKL-40 in patients with metastatic prostate cancer (PC) at the time of diagnosis are associated to poor prognosis. In this study, we evaluated the value of these biomarkers in monitoring the patients during hormonal treatment.
  
  
  METHODS
  Serum procollagen type I N-terminal propeptide (PINP), bone-specific alkaline phosphatase (BAP), CTX-I, and YKL-40 were determined by ELISA in a longitudinal study of 106 patients with metastatic PC during treatment with total androgen ablation or parenteral estrogen. Serum samples were collected with 3 months interval. Median observation time was 4.9 years (range, 3.6-6.2). A total of 78 patients died (64 within 7 months following the last blood sampling).
  
  
  RESULTS
  After 6 months treatment, serum PINP, BAP, and YKL-40 decreased (P < 0.0001), but not serum CTX-I compared with baseline values. Univariate Cox analysis showed that serum PINP at 6 months [log transformed and treated as a continuous variable; hazard ratio (HR), 2.2; P < 0.0001], serum BAP (HR, 1.8; P < 0.0001), and serum CTX-I (HR, 2.4; P < 0.0001), but not serum YKL-40 (HR, 1.4; P = 0.16) were associated with survival. Multivariate Cox analysis including the biomarkers 6 months after the start of treatment showed that Soloway score (HR, 3.9; P = 0.013), WHO tumor grade (HR, 3.9; P = 0.004), and serum PINP (HR, 2.2; P < 0.0001) were independent prognostic variables of survival. Scoring the biomarkers during treatment as time-dependent covariates in univariate Cox regression analysis showed that increases in serum PINP (HR, 2.0; P < 0.0001), BAP (HR, 2.1; P < 0.0001), and YKL-40 (HR, 2.1; P < 0.0001) were predictors of early death.
  
  
  CONCLUSIONS
  Serial monitoring of serum PINP, BAP, CTX-I, and YKL-40 in metastatic PC patients during hormonal treatment provided information of prognosis.
authors.affiliation: Department of Rheumatology, Herlev Hospital, , Denmark. julia.johansen@post3.tele.dk
authors.forename: Julia S
authors.initials: JS
authors.lastname: Johansen
authors.forename: Klaus
authors.initials: K
authors.lastname: Brasso
authors.forename: Peter
authors.initials: P
authors.lastname: Iversen
authors.forename: Børge
authors.initials: B
authors.lastname: Teisner
authors.forename: Patrick
authors.initials: P
authors.lastname: Garnero
authors.forename: Paul A
authors.initials: PA
authors.lastname: Price
authors.forename: Ib Jarle
authors.initials: IJ
authors.lastname: Christensen
mesh_terms: D054392:Adipokines; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor; D001842:Bone and Bones / Q000187:drug effects* / Q000473:pathology; D000071451:Chitinase-3-Like Protein 1; D006023:Glycoproteins / Q000096:biosynthesis* / Q000737:chemistry; D006728:Hormones / Q000378:metabolism*; D006801:Humans; D037102:Lectins; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009368:Neoplasm Transplantation; D010446:Peptide Fragments / Q000737:chemistry; D011347:Procollagen / Q000737:chemistry; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology*; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D054392:Adipokines; D014408:Biomarkers, Tumor; C084533:CHI3L1 protein, human; D000071451:Chitinase-3-Like Protein 1; D006023:Glycoproteins; D006728:Hormones; D037102:Lectins; D010446:Peptide Fragments; D011347:Procollagen; C047202:procollagen Type I N-terminal peptide