title: The relationship between prostate specific antigen change and biopsy progression in patients on active surveillance for prostate cancer.
abstract: OBJECTIVE
  We assessed whether an association exists between a change in prostate specific antigen and biopsy progression in men on active surveillance.
  
  
  METHODS
  A cohort of patients undergoing active surveillance for prostate cancer was identified from the urological oncology database at our institution. Multivariate logistic regression was performed to determine whether prostate specific antigen velocity, defined as the change in ln(prostate specific antigen) per year, is associated with biopsy progression, defined as a Gleason upgrade or volume progression on repeat biopsy within 24 months of diagnosis.
  
  
  RESULTS
  A total of 241 men with a mean ± SD age of 61 ± 7 years and mean prostate specific antigen 4.9 ± 2.2 ng/ml met study inclusion criteria. Median time to repeat biopsy was 10 months (IQR 6-13). Biopsy progression developed in 55 men (23%), including a Gleason score upgrade in 46 (19%), greater than 33% positive cores in 11 (5%) and greater than 50% maximum single core positive in 12 (5%). The median prostate specific antigen ratio per year was 1.0 (IQR 0.95-1.03), although 1 man had a ratio of greater than 1.26 (doubled over 3 years) and 7 had a ratio of less than 1/1.26 (halved over 3 years). On multivariate analysis prostate specific antigen doubling within 3 years was associated with a 1.4-fold increase in the odds of biopsy progression (OR 1.4, 95% CI 0.6-3.4, p = 0.46).
  
  
  CONCLUSIONS
  There is little change in prostate specific antigen during the first 24 months of surveillance in men with well staged, low risk prostate cancer. We believe that these findings highlight the importance of repeat biopsy during surveillance.
authors.affiliation: Department of Urology, University of California-San Francisco, San Francisco, California 94143, USA. jwhitson@urology.ucsf.edu
authors.forename: Jared M
authors.initials: JM
authors.lastname: Whitson
authors.forename: Sima P
authors.initials: SP
authors.lastname: Porten
authors.forename: Joan F
authors.initials: JF
authors.lastname: Hilton
authors.forename: Janet E
authors.initials: JE
authors.lastname: Cowan
authors.forename: Nannette
authors.initials: N
authors.lastname: Perez
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Cooperberg
authors.forename: Kirsten L
authors.initials: KL
authors.lastname: Greene
authors.forename: Maxwell V
authors.initials: MV
authors.lastname: Meng
authors.forename: Jeff P
authors.initials: JP
authors.lastname: Simko
authors.forename: Katsuto
authors.initials: K
authors.lastname: Shinohara
authors.forename: Peter R
authors.initials: PR
authors.lastname: Carroll
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood; D001706:Biopsy; D015331:Cohort Studies; D018450:Disease Progression; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D011237:Predictive Value of Tests; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen