title: Yearly prostate specific antigen and digital rectal examination fluctuations in a screened population.
abstract: OBJECTIVE
  Prostate biopsy is often recommended based on increases in prostate specific antigen and/or abnormal digital rectal examination. We investigated the stability of a single positive test during the next 3 consecutive years.
  
  
  METHODS
  A total of 2,578 participants in a San Antonio screening cohort with 2 or more consecutive annual prostate specific antigen and digital rectal examination tests were identified. Occurrences of an increased prostate specific antigen (2.5 ng/ml or greater) followed by 1 or more nonincreased prostate specific antigen results were compared with similar fluctuations of digital rectal examination from abnormal to normal.
  
  
  RESULTS
  In 2,272 men who did not have a biopsy during the study, in 23.3% of 744 incidences of an increased prostate specific antigen with 1 year of followup, the next prostate specific antigen was not increased. In 19.5% of 462 incidences of an increased prostate specific antigen with 2 years of followup, the next 2 consecutive prostate specific antigen levels were not increased. Finally, in 17.5% of 285 incidences of an increased prostate specific antigen with 3 years of followup, the next 3 consecutive prostate specific antigens were not increased. Rates were similar but lower in 221 men with 1 or more negative biopsies during the study and in 85 men in whom prostate cancer eventually developed during the study. In contrast, approximately 70% of abnormal digital rectal examinations were normal the following year even in patients with prostate cancer, and in the majority of incidences remained normal the next 2 to 3 consecutive years.
  
  
  CONCLUSIONS
  Occurrences of reversed prostate specific antigen cut point or abnormal digital rectal examination based decisions to biopsy 1 or more years after the initial test are not uncommon, suggesting repetition of these tests.
authors.affiliation: Depatment of Urology, University of Texas Health Sciences Center, San Antonio, Texas, USA. ankerst@uthscsa.edu
authors.forename: Donna Pauler
authors.initials: DP
authors.lastname: Ankerst
authors.forename: Ryan
authors.initials: R
authors.lastname: Miyamoto
authors.forename: Prakash Vijay
authors.initials: PV
authors.lastname: Nair
authors.forename: Brad H
authors.initials: BH
authors.lastname: Pollock
authors.forename: Ian M
authors.initials: IM
authors.lastname: Thompson
authors.forename: Dipen J
authors.initials: DJ
authors.lastname: Parekh
mesh_terms: D000328:Adult; D000368:Aged; D001707:Biopsy, Needle; D002173:Cancer Care Facilities; D015331:Cohort Studies; D051517:Digital Rectal Examination; D018450:Disease Progression; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D009367:Neoplasm Staging; D019370:Observation / Q000379:methods*; D011336:Probability; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000503:physiopathology; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D013781:Texas; D013997:Time Factors
chemical_list: D017430:Prostate-Specific Antigen