Diagnostic Accuracy of Urinary PCA3 for Prostate Cancer in Thai Patients With PSA Levels of 3 to 10 ng/ml Undergoing an Initial Prostate Biopsy

Purpose: To examine the diagnostic accuracy of the urinary prostate cancer gene 3 score for prostate cancer in Thai patients with prostate-specific antigen levels of 3 to 10 ng/ml undergoing an initial prostate biopsy. Materials and methods: In this prospective, single-center study, urine samples were collected after prostate massage. Urinary prostate cancer gene 3 mRNA levels were measured by real-time quantitative polymerase chain reaction. Data, including age, biopsy results, preoperative prostate-specific antigen levels, prostate-specific antigen density, prostate-specific antigen velocity, prostate volume, and prostate imaging findings, were collected between June 1, 2020, and May 15, 2021. Results: The median prostate-specific antigen level of the 70 included patients was 6.31 ng/ml. Sixteen patients had positive biopsy results (22.9%). The prostate cancer gene 3 score (695.09 vs 268.79, P < .01), prostate-specific antigen density (0.19 vs 0.13, P < .01), and prostate-specific antigen velocity (2.68 vs 0.44, P < .01) significantly differed between the positive and negative biopsy groups. The predictive power of the prostate cancer gene 3 score was evaluated using receiver operating characteristic curves. At a prostate cancer gene 3 score threshold of 366.02, the sensitivity and specificity were 78.57% and 79.25%, respectively. Meanwhile, the areas under the curve of the prostate cancer gene 3 score, prostate-specific antigen velocity, and prostate-specific antigen density were better than that of prostate-specific antigen for predicting a positive biopsy. Conclusion: Our study confirmed the diagnostic accuracy of prostate cancer gene 3 for predicting a positive biopsy in Thai men with prostate-specific antigen levels of 3 to 10 ng/mL. Combining the prostate cancer gene 3 score and prostate-specific antigen derivatives might be helpful for identifying patients who can avoid unnecessary biopsies and subsequent complications.