title: Can effect of finasteride on prostate-specific antigen be used to decrease repeat prostate biopsy?
abstract: OBJECTIVE
  Patients often undergo multiple prostate biopsies for persistently elevated prostate-specific antigen (PSA) levels. Finasteride decreases serum PSA by approximately 50%. We performed a pilot study to examine the correlation among finasteride, PSA, and PSA density (PSAD) to identify patients who could be excluded from repeat prostate biopsy.
  
  
  METHODS
  We performed a prospective study from 2001 to 2002 on 25 men with elevated PSA levels. These patients had prior negative prostate biopsy findings. At study onset, the patients' PSA level and PSAD were measured. Patients were instructed to take finasteride 5 mg for 6 months. PSA and PSAD determination and prostate biopsies were repeated at 6 months and the findings compared with the initial results.
  
  
  RESULTS
  The mean patient age was 67.2 years (median 62). The median PSA level was 8.3 ng/dL at study entry (mean 9.34) and 4.6 ng/dL (mean 5.09) at 6 months. The median PSAD was 0.18 (mean 0.20) at study entry and 0.09 (mean 0.12) at 6 months. Of the 23 patients who completed the study, 6 (26%) were diagnosed with prostate cancer. At study entry, the median PSA level in those with prostate cancer was 9.6 ng/dL and was 5.8 ng/dL at 6 months. Patients without prostate cancer on repeat biopsy had a 44% decrease in PSAD. Patients with prostate cancer had a 5% decrease in PSAD.
  
  
  CONCLUSIONS
  The results of our study have demonstrated that patients without prostate cancer have a greater decrease in PSAD when taking finasteride than those with prostate cancer. This pilot study had a small population with limited power, and a repeat prospective study with a larger population is warranted.
authors.affiliation: Department of Urology, Brown University/Roger Williams Medical Center, Providence, Rhode Island 02904, USA.
authors.forename: Liann Nicole
authors.initials: LN
authors.lastname: Handel
authors.forename: Saurabh
authors.initials: S
authors.lastname: Agarwal
authors.forename: Stephen F
authors.initials: SF
authors.lastname: Schiff
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Kelty
authors.forename: Steven I
authors.initials: SI
authors.lastname: Cohen
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D001706:Biopsy / Q000706:statistics & numerical data / Q000639:trends; D003937:Diagnosis, Differential; D019160:Endosonography; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D018120:Finasteride / Q000494:pharmacology*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood / Q000187:drug effects*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000000981:diagnostic imaging / Q000473:pathology*; D012189:Retrospective Studies
chemical_list: D014408:Biomarkers, Tumor; D004791:Enzyme Inhibitors; D018120:Finasteride; D017430:Prostate-Specific Antigen