title: Prostate specific-antigen distribution in asymptomatic Canadian men with no clinical evidence of prostate cancer.
abstract: OBJECTIVE
  To examine prostate specific-antigen (PSA) levels and percentage free/total PSA (f/tPSA) distributions as well as digital rectal examination (DRE) profiles in asymptomatic Canadian men with no established prostate cancer diagnosis, as recent data indicate that a man's risk of developing prostate cancer is higher if his baseline PSA level is above the median for his age group.
  
  
  METHODS
  We used data obtained during an early prostate cancer-detection event. An invitation to an onsite DRE, PSA level and f/tPSA assessment was accepted by 313 men. Serum PSA level and f/tPSA were measured before the DRE. A suspicious DRE and/or PSA level of > or = 2.5 ng/mL or f/tPSA of < or = 15% represented indications for a systematic 12-core ultrasonography-guided prostate biopsy.
  
  
  RESULTS
  Of all the 313 men, most (235, 75%) had PSA levels of 0.01-1.53 ng/mL and an f/tPSA of >15% (285, 91.1%). The median (range) PSA level was 0.8 (0-34.2) ng/mL and f/tPSA was 27.4 (6.7-100)%. Age-specific median PSA levels and f/tPSA were, respectively, 0.7, 0.9, 1.0, 1.5 ng/mL and 31%, 27%, 26%, 25% for men aged 40-49, 50-59, 60-69 and 70-79 years. A suspicious DRE was recorded in 55 (17.6%) men, with eight (8.8%), 26 (20.0%), 14 (20.6%), and seven (28.9%) having suspicious DRE findings according to above age categories. Overall, seven (2.2%) prostate cancers were detected.
  
  
  CONCLUSIONS
  The median age-specific baseline PSA levels and f/tPSA represent valuable indicators of prostate cancer risk. The population-specific baseline median PSA level should not be >1.0 ng/mL and the baseline f/tPSA should be >30%. Men with values outside of these ranges should be considered at greater risk of prostate cancer.
authors.affiliation: Cancer Prognostics and Health Outcomes Unit, University of Montreal, Montreal, Quebec, Canada.
authors.forename: Felix K-H
authors.initials: FK
authors.lastname: Chun
authors.forename: Paul
authors.initials: P
authors.lastname: Perrotte
authors.forename: Alberto
authors.initials: A
authors.lastname: Briganti
authors.forename: Serge
authors.initials: S
authors.lastname: Benayoun
authors.forename: Thierry
authors.initials: T
authors.lastname: Lebeau
authors.forename: Alvaro
authors.initials: A
authors.lastname: Ramirez
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Lewinshtein
authors.forename: Luc
authors.initials: L
authors.lastname: Valiquette
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Guay
authors.forename: Pierre I
authors.initials: PI
authors.lastname: Karakiewicz
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000097:blood*; D002170:Canada; D051517:Digital Rectal Examination; D042241:Early Diagnosis; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000175:diagnosis*; D012016:Reference Values; D018570:Risk Assessment / Q000379:methods
chemical_list: D017430:Prostate-Specific Antigen