title: Utility of PCA3 in patients undergoing repeat biopsy for prostate cancer.
abstract: BACKGROUND
  Men with persistently elevated and/or rising PSA levels after negative prostate biopsy often undergo multiple repeat biopsies. Prostate cancer antigen 3 (PCA3) has emerged as a predictor of prostate cancer.
  
  
  METHODS
  We sought to define the utility of PCA3 in combination with other clinical data in predicting the risk of prostate cancer on repeat biopsy. We retrospectively obtained PCA3, PSA, PSA density (PSAD), digital rectal examination (DRE) and transrectal ultrasound (TRUS) findings from 103 patients at a single institution who had at least one prior negative prostate biopsy. The sensitivity and specificity of PCA3 in detecting prostate cancer was determined. Receiver operating characteristics curves were produced for each variable individually and in multivariable analysis, controlling for PCA3, PSAD, TRUS, PSA and DRE. A nomogram was created, internally validated and compared to another recently published nomogram.
  
  
  RESULTS
  Of the 103 patients, 37 (31%) had prostate cancer on repeat biopsy. The sensitivity and specificity of PCA3 (using a cut point of 25) was 0.67 and 0.64, respectively. In multivariable analyses, PCA3 was independently associated with prostate cancer (odds ratio: 1.02, 95% confidence interval: 1.01-1.04), with area under the curve (AUC) of 0.64. A multivariable model containing PCA3, PSAD, PSA, DRE and TRUS findings showed the most diagnostic accuracy (AUC: 0.82).
  
  
  CONCLUSIONS
  In the setting of prior negative biopsies, PCA3 was independently associated with prostate cancer in a multivariable model. In combination with other clinical data, PCA3 is a valuable tool in assessing the risk of prostate cancer on repeat biopsy.
authors: Department of Urology, University of California, San Francisco, UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, CA, USA.
authors: A K
authors: AK
authors: Wu
authors: A C
authors: AC
authors: Reese
authors: M R
authors: MR
authors: Cooperberg
authors: N
authors: N
authors: Sadetsky
authors: K
authors: K
authors: Shinohara
mesh_terms: D000368:Aged; D000951:Antigens, Neoplasm / Q000652:urine*; D019540:Area Under Curve; D014408:Biomarkers, Tumor / Q000097:blood / Q000652:urine*; D001706:Biopsy; D051517:Digital Rectal Examination; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011467:Prostate / Q000000981:diagnostic imaging / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis / Q000473:pathology / Q000652:urine*; D012372:ROC Curve; D012189:Retrospective Studies; D014463:Ultrasonography
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; C479341:prostate cancer antigen 3, human; D017430:Prostate-Specific Antigen