title: Ultrasensitive prostate specific antigen and its role after radical prostatectomy: a systematic review.
abstract: OBJECTIVE
  Prostate specific antigen is an important tool to monitor patients with prostate cancer after radical prostatectomy. Ultrasensitive prostate specific antigen assays are increasingly used with a lower limit of detection as low as 0.001 ng/ml. We systematically reviewed currently available ultrasensitive prostate specific antigen technologies and the role of this method in monitoring patients after radical prostatectomy.
  
  
  METHODS
  We searched the relevant literature using the MEDLINE® database. For various study objectives the series eligible for review provided serial ultrasensitive prostate specific antigen (lower detection limit less than 0.1 ng/ml) data on men after radical prostatectomy as well as comparative data on standard prostate specific antigen (lower detection limit 0.1 ng/ml or greater).
  
  
  RESULTS
  Ultrasensitive prostate specific antigen could potentially detect prostate cancer recurrence years earlier than standard prostate specific antigen assays. The specificity of detectable ultrasensitive prostate specific antigen is low. Ultrasensitive prostate specific antigen kinetics may improve the positive predictive value for detecting cancer recurrence. However, the usefulness of prostate specific antigen doubling time at the ultrasensitive level remains controversial. Undetectable nadir ultrasensitive prostate specific antigen after radical prostatectomy confers a low risk of disease recurrence while a detectable nadir above 0.01 ng/ml requires additional measurement and consideration of other risk factors to determine management and avoid overtreatment. This monitoring method may spare patients with high risk disease adjuvant radiation therapy and enable more selective early salvage radiation. Currently no data demonstrate improved survival after early salvage therapy prompted by ultrasensitive prostate specific antigen surveillance.
  
  
  CONCLUSIONS
  Ultrasensitive prostate specific antigen is useful in the early diagnosis of cancer recurrence after radical prostatectomy but specificity is poor. To date there is a lack of evidence that earlier detection of recurrence translates into prolonged time to metastasis. Integrating ultrasensitive prostate specific antigen with other clinicopathological factors can help determine optimal adjuvant and salvage therapy.
authors.affiliation: Martini-Clinic Prostate Cancer Center and Department of Urology, University Hospital Hamburg-Eppendorf, Hamburg, Germany; Department of Urology, School of Medicine, University of California-Davis, Sacramento, California. Electronic address: d.tilki@uke.de.
authors.forename: Derya
authors.initials: D
authors.lastname: Tilki
authors.affiliation: Department of Urology, School of Medicine, University of California-Davis, Sacramento, California; Department of Urology, Ajou University School of Medicine, Suwon, Republic of Korea.
authors.forename: Sun Il
authors.initials: SI
authors.lastname: Kim
authors.affiliation: Department of Urology, School of Medicine, University of California-Davis, Sacramento, California.
authors.forename: Brian
authors.initials: B
authors.lastname: Hu
authors.affiliation: Department of Urology, School of Medicine, University of California-Davis, Sacramento, California.
authors.forename: Marc A
authors.initials: MA
authors.lastname: Dall'Era
authors.affiliation: Department of Urology, School of Medicine, University of California-Davis, Sacramento, California.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Evans
mesh_terms: D006801:Humans; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000097:blood*; D017430:Prostate-Specific Antigen / Q000097:blood*; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000097:blood* / Q000601:surgery*; D012680:Sensitivity and Specificity
chemical_list: D017430:Prostate-Specific Antigen
keywords: diagnosis; local; neoplasm recurrence; prostate-specific antigen; prostatectomy; prostatic neoplasms