title: Positive prostate-specific antigen circulating cells detected by reverse transcriptase-polymerase chain reaction does not imply the presence of prostatic micrometastases.
abstract: OBJECTIVE
  Detection of circulating tumor cells may improve the preoperative local staging of prostate cancers. The aim of this study was to perform enhanced reverse transcriptase-polymerase chain reaction (RT-PCR) of prostate-specific antigen (PSA) mRNA to define the predictive value of PSA-positive circulating cells in a large series of patients.
  
  
  METHODS
  The study included 46 patients with Stage T1 to T2 prostate cancer, 94 with benign prostatic hyperplasia (BPH), and 51 (including 9 women) with nonprostatic disease. PSA-positive cells from peripheral blood samples were detected by Southern blot analysis of the RT-PCR products. Original oligonucleotide primers were defined to exclusively detect the three PSA mRNA splices.
  
  
  RESULTS
  Circulating PSA-positive cells were observed in 8 (8.5%) of 94 patients with BPH, 10 (22%) of 46 with Stage T1 to T2 prostate cancer, and 9 (17.6%) of 51 with nonprostatic disease. The detection rate of PSA-positive circulating cells was significantly increased in patients with prostate cancer versus patients with BPH (P = 0.03). Among clinically localized prostate cancers with a Gleason score less than 8, a correlation was observed between PSA-positive circulating cells and Stage pT3 cancer (P = 0.038), capsular penetration (P = 0.04), and a positive margin (P = 0.038). The specificity of the assay for Stage pT3 cancer detection was 84.6%, with a positive predictive value of 60%.
  
  
  CONCLUSIONS
  Although RT-PCR assay may have a role in preoperative local staging, this study demonstrated the absence of tissue and tumor specificity of PSA-positive circulating cells, accounting for the weak positive predictive value of this technique.
authors.affiliation: Clinique Urologique, Hôpital Cochin, Université Paris V, France.
authors.forename: N
authors.initials: N
authors.lastname: Thiounn
authors.forename: F
authors.initials: F
authors.lastname: Saporta
authors.forename: T A
authors.initials: TA
authors.lastname: Flam
authors.forename: F
authors.initials: F
authors.lastname: Pages
authors.forename: M
authors.initials: M
authors.lastname: Zerbib
authors.forename: A
authors.initials: A
authors.lastname: Vieillefond
authors.forename: E
authors.initials: E
authors.lastname: Martin
authors.forename: B
authors.initials: B
authors.lastname: Debré
authors.forename: S
authors.initials: S
authors.lastname: Chevillard
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009360:Neoplastic Cells, Circulating / Q000737:chemistry*; D016133:Polymerase Chain Reaction / Q000379:methods; D011237:Predictive Value of Tests; D017430:Prostate-Specific Antigen / Q000032:analysis* / Q000235:genetics; D011470:Prostatic Hyperplasia / Q000097:blood / Q000473:pathology; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology*; D012333:RNA, Messenger / Q000032:analysis; D012680:Sensitivity and Specificity
chemical_list: D012333:RNA, Messenger; D017430:Prostate-Specific Antigen