OBJECTIVE: To establish and verify the utility of measuring urine prostate cancer antigen 3 (PCA3) mRNA levels in the diagnosis of prostate cancer among Hong Kong Chinese patients.
DESIGN: Cross-sectional study.
SETTING: Urology Unit of a regional hospital in Hong Kong.
PATIENTS: This study was carried out in two parts. In the first part, 102 post-prostatic massage urine samples were collected from patients with known prostate cancer (38 patients) and controls (64 patients, with normal digital rectal examination and serum prostate-specific antigen < 4 ng/mL). The urine levels of PCA3 and prostate-specific antigen mRNA were measured and the best cut-off point for differentiating cancer was determined. In the second part of the study, post-prostatic massage urine samples from 47 patients with clinically suspected prostate cancer were collected prior to prostate biopsy. The performance of PCA3 as a diagnostic aid for cancer was then assessed using the aforementioned cut-off value.
RESULTS: In the first part of the study, the best cut-off for the PCA3 ratio (defined as the ratio of the Ct value of PCA3/PSA mRNA) was 1.127. Applying this cut-off to the 47 patients with clinically suspected prostate cancer and no history of previous prostate biopsy, the sensitivity and specificity of PCA3 for diagnosing prostate cancer were 71% and 92%, respectively.
CONCLUSION: The post-prostatic massage urine PCA3 level shows utility for diagnosing prostate cancer in patients with elevated prostate-specific antigen levels that could facilitate decisions to undertake prostate biopsy and avoid unnecessary biopsies.
Written by:
Ng CF, Yeung R, Chiu PK, Lam NY, Chow J, Chan B. Are you the author?
Division of Urology, Department of Surgery, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong.
Reference: Hong Kong Med J. 2012 Dec;18(6):459-65.
PubMed Abstract
PMID: 23223645
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