title: Significance of prostate-specific antigen--alpha(1)-antichymotrypsin complex for diagnosis and staging of prostate cancer.
abstract: OBJECTIVE
  To evaluate the clinical significance of measuring the prostate-specific antigen-alpha(1)-antichymotrypsin (PSA-ACT) for differentiating prostate cancer from benign prostate hypertrophy (BPH) and for the staging of prostate cancer.
  
  
  METHODS
  Before treatment, total PSA (tPSA) and PSA-ACT were measured in 120 patients with prostate cancer and in 150 patients with BPH using immunofluorometric techniques with different monoclonal antibodies against PSA and ACT. Furthermore, the tPSA and PSA-ACT densities of the whole prostate (PSAD and ACTD, respectively) were calculated.
  
  
  RESULTS
  tPSA, PSAD, PSA-ACT and ACTD levels in patients with prostate cancer paralleled the clinical stage and were significantly higher than those in patients with BPH. Furthermore, these four values were significantly higher in patients with pathologically extraprostatic disease than those with organ-confined disease. Receiver operating characteristics analysis among patients with PSA values of 4.1-10 ng/ml revealed that the areas under the curve for tPSA and ACTD were similar to those for PSA-ACT and ACTD, respectively and that no significant differences in the differentiation between prostate cancer and BPH were observed among these parameters.
  
  
  CONCLUSIONS
  Measurement of PSA-ACT provides useful information for the clinical staging of prostate cancer and differential diagnosis between prostate cancer and BPH; however, compared with tPSA, PSA-ACT may not be significantly superior in the diagnosis and staging of prostate cancer.
authors.affiliation: Department of Urology, Kobe University School of Medicine, Kobe, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Hara
authors.forename: H
authors.initials: H
authors.lastname: Miyake
authors.forename: S
authors.initials: S
authors.lastname: Hara
authors.forename: Y
authors.initials: Y
authors.lastname: Yamada
authors.forename: Y
authors.initials: Y
authors.lastname: Takechi
authors.forename: M
authors.initials: M
authors.lastname: Fujisawa
authors.forename: H
authors.initials: H
authors.lastname: Okada
authors.forename: S
authors.initials: S
authors.lastname: Arakawa
authors.forename: S
authors.initials: S
authors.lastname: Kamidono
mesh_terms: D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D009367:Neoplasm Staging; D017430:Prostate-Specific Antigen / Q000097:blood*; D011470:Prostatic Hyperplasia / Q000175:diagnosis; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology; D012680:Sensitivity and Specificity; D000514:alpha 1-Antichymotrypsin / Q000097:blood*
chemical_list: D000514:alpha 1-Antichymotrypsin; D017430:Prostate-Specific Antigen