title: The free-to-total serum prostate specific antigen ratio for staging prostate carcinoma.
abstract: OBJECTIVE
  We analyzed the relationship between the free-to-total PSA ratio and prostate cancer tumor stage and grade compared to total serum PSA.
  
  
  METHODS
  In 123 patients clinical and pathological grade and stage were related to total serum PSA and free-to-total PSA ratio.
  
  
  RESULTS
  Total serum PSA paralleled clinical staging of prostate cancer. The distributions of total serum PSA and the free-to-total PSA ratio were significantly different between benign and malignant diseases (any stage), and between any T category and nodal disease. For serum PSA significant differences were noted between the distributions of men with locally confined (stages T1 and T2) and locally extended (stage T3) disease, and between all T categories and systemic metastatic disease. This finding was not noted for the free-to-total PSA ratio.
  
  
  CONCLUSIONS
  The free-to-total PSA ratio has no additional value in clinical staging of prostate carcinoma compared to serum PSA. The free-to-total PSA ratio may be considered the result of cell differentiation and not an indicator of tumor load.
authors.affiliation: Department of Urology, Academic Hospital Rotterdam, The Netherlands.
authors.forename: C H
authors.initials: CH
authors.lastname: Bangma
authors.forename: R
authors.initials: R
authors.lastname: Kranse
authors.forename: B G
authors.initials: BG
authors.lastname: Blijenberg
authors.forename: F H
authors.initials: FH
authors.lastname: Schröder
mesh_terms: D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology*
chemical_list: D017430:Prostate-Specific Antigen