title: Effect of hemodialysis on serum complexed prostate-specific antigen levels.
abstract: OBJECTIVE
  The measurement of prostate-specific antigen (PSA) is a useful tool in the screening and follow-up of prostate cancer, but its diagnostic validity is uncertain in hemodialysis patients. The aim of this study was to evaluate the effects of hemodialysis on serum complexed PSA (cPSA) levels.
  
  
  METHODS
  A total of 36 men (mean age 62.54+/-8.20 years) with end-stage renal disease were enrolled in a prospective study. Serum total PSA (tPSA), free PSA (fPSA) and cPSA, and hematocrit levels were measured before and immediately after dialysis using low-flux membranes in the serum and in the dialysis ultrafiltrate.
  
  
  RESULTS
  After hemodialysis, cPSA, fPSA and the fPSA:tPSA ratio increased significantly (p<0.05). However, there was no significant increase in tPSA. fPSA, cPSA and tPSA were not detected in ultrafiltrate. Hematocrit levels increased significantly (p<0.0001) due to hemoconcentration. Of patients with initial serum tPSA and cPSA values and fPSA:tPSA ratios below the cut-off values, none had a post-hemodialysis value greater than the cut-off point. There were weak correlation between the difference in values after and before hemodialysis of hematocrit and cPSA (p=0.035), and between the percentage change in levels before and after hemodialysis of hematocrit and cPSA (p=0.041).
  
  
  CONCLUSIONS
  Hemodialysis induced elevations in all forms of PSA, but tPSA was the least affected form. cPSA did not show any diagnostic superiority over other forms of PSA. Thus, serum tPSA remains a reliable parameter for follow-up of prostate cancer in uremic patients receiving long-term dialysis. However, further research is needed to explain the pathophysiology of alterations in the concentrations of different forms of PSA.
authors.affiliation: Urology Clinic, Kartal Training and Research Hospital, Istanbul, Turkey. tarhanf@yahoo.com
authors.forename: Fatih
authors.initials: F
authors.lastname: Tarhan
authors.forename: Asuman
authors.initials: A
authors.lastname: Orçun
authors.forename: Inci
authors.initials: I
authors.lastname: Küçükercan
authors.forename: Nazan
authors.initials: N
authors.lastname: Camursoy
authors.forename: Ugur
authors.initials: U
authors.lastname: Kuyumcuoglu
mesh_terms: D000368:Aged; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood*; D006435:Renal Dialysis
chemical_list: D017430:Prostate-Specific Antigen