title: Prediction of prostate volume based on total and free serum prostate-specific antigen: is it reliable?
abstract: OBJECTIVE
  To analyze the utility of total/free prostate-specific antigen (PSA) and age as predictors of the prostate volume in men with symptomatic benign prostatic hyperplasia (BPH) and no evidence of prostate cancer.
  
  
  METHODS
  Total and free serum PSA were determined in 681 patients with normal digital rectal examination and symptomatic BPH using the Hybritech method. Prostate volume was measured by transrectal ultrasound (TRUS). TRUS-guided biopsy was performed in 459 (67.4%) of the patients with a serum PSA >4.0 ng/ml.
  
  
  RESULTS
  The relationship with prostate volume was best described in a log linear fashion by free PSA (R(2) = 0.367), total PSA (R(2) = 0.264) and age (R(2) = 0.017). Multiple linear regression demonstrates no significant influence of age. Free PSA was able to predict the individual TRUS prostate volume +/-10% in 67% of the patients and +/-20% in 91.2% and total PSA in 63 and 90. 9%, respectively.
  
  
  CONCLUSIONS
  Prostate volume is strongly related with free and total PSA. Both determinations would be able to predict the TRUS prostate volume +/-20% in more than 90% of the patients.
authors.affiliation: Department of Urology and Prostatic Pathology Unit, Vall d'Hebron Hospital, Universidad Autónoma de Barcelona, Spain. morote@hg.vhebron.es
authors.forename: J
authors.initials: J
authors.lastname: Morote
authors.forename: G
authors.initials: G
authors.lastname: Encabo
authors.forename: M
authors.initials: M
authors.lastname: López
authors.forename: I M
authors.initials: IM
authors.lastname: de Torres
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D017430:Prostate-Specific Antigen / Q000097:blood*; D011470:Prostatic Hyperplasia / Q000097:blood* / Q000000981:diagnostic imaging / Q000473:pathology*; D015203:Reproducibility of Results; D014463:Ultrasonography
chemical_list: D017430:Prostate-Specific Antigen