title: Circulating tumor cells predict survival in patients with metastatic prostate cancer.
abstract: OBJECTIVE
  To determine whether circulating tumor cells (CTCs) predict for survival in patients with metastatic prostate cancer (PCa) and to compare its prognostic abilities with other clinical factors.
  
  
  METHODS
  Blood samples from 37 patients with metastatic PCa were analyzed for CTCs. CTCs were enriched from 7.5 mL blood using magnetic nanoparticles targeting the epithelial cell adhesion molecule and then fluorescently labeled. The samples were analyzed by multiparameter flow cytometry, and events with appropriate light scatter properties that were nucleic acid dye positive, cytokeratin positive, and CD45 negative were defined as CTCs.
  
  
  RESULTS
  The number of CTCs found ranged from 0 to 8586 per 7.5 mL (mean 530 +/- 1887, median 5). A threshold of 5 or more CTCs per 7.5 mL of blood was used to evaluate the ability of CTCs to predict for overall survival. Of the 37 patients, 23 (62%) had 5 or more CTCs, with a median overall survival of 0.70 year compared with more than 4 years for those patients with fewer than 5 CTCs (log-rank P = 0.002, Cox hazards ratio 7.4). In the subset of 26 patients with hormone-refractory PCa, the presence of CTCs was the most significant parameter predictive of survival in univariate and multivariate analyses.
  
  
  CONCLUSIONS
  In this pilot study, the presence of 5 or more CTCs in 7.5 mL blood was associated with poor overall survival in patients with metastatic PCa.
authors.affiliation: Department of Urology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Jose G
authors.initials: JG
authors.lastname: Moreno
authors.forename: M Craig
authors.initials: MC
authors.lastname: Miller
authors.forename: Steve
authors.initials: S
authors.lastname: Gross
authors.forename: W Jeffrey
authors.initials: WJ
authors.lastname: Allard
authors.forename: Leonard G
authors.initials: LG
authors.lastname: Gomella
authors.forename: Leon W M M
authors.initials: LW
authors.lastname: Terstappen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002452:Cell Count; D006801:Humans; D008297:Male; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000401:mortality* / Q000473:pathology*; D015996:Survival Rate