Japanese Journal of Clinical Oncology 31:506-509 (2001)
© 2001 Foundation for Promotion of Cancer Research
Significance of Prostate-specific Antigen
1-Antichymotrypsin Complex for Diagnosis and Staging of Prostate Cancer

1Department of Urology, Kobe University School of Medicine, Kobe and 2 Department of Urology, Hyogo Perceptual Awaji Hospital, Sumoto, Japan
Objective: To evaluate the clinical significance of measuring the prostate-specific antigen
1-antichymotrypsin (PSAACT) for differentiating prostate cancer from benign prostate hypertrophy (BPH) and for the staging of prostate cancer.
Methods: Before treatment, total PSA (tPSA) and PSAACT 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 PSAACT densities of the whole prostate (PSAD and ACTD, respectively) were calculated.
Results: tPSA, PSAD, PSAACT 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 4.110 ng/ml revealed that the areas under the curve for tPSA and ACTD were similar to those for PSAACT and ACTD, respectively and that no significant differences in the differentiation between prostate cancer and BPH were observed among these parameters.
Conclusions: Measurement of PSAACT provides useful information for the clinical staging of prostate cancer and differential diagnosis between prostate cancer and BPH; however, compared with tPSA, PSAACT may not be significantly superior in the diagnosis and staging of prostate cancer.
+ For reprints and all correspondence: Isao Hara, Department of Urology, Kobe University School of Medicine, 751 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan
Abbreviations: PSA, prostate-specific antigen; ACT,
1-antichymotrypsin; tPSA, total PSA; PSAD, PSA density; ACTD, PSAACT density; DRE, digital rectal examination; TRUS, transrectal ultrasound; AP, anteroposterior; TR, transverse; SI, superiorinferior; ROC, receiver operating characteristic; AUC, area under the curve; BPH, benign prostatic hypertrophy