The prostate cancer gene 3 (PCA3) urine test in men with previous negative biopsies: does free-to-total prostate-specific antigen ratio influence the performance of the PCA3 score in predicting positive biopsies?

OBJECTIVE: to determine the performance characteristics of the prostate cancer gene 3 (PCA3) score on the outcome of biopsy relative to different ranges of free-to-total prostate-specific antigen (PSA) ratio (f/tPSA) in men with a previous negative biopsy and a PSA level of 2.5-10 ng/mL, as urine tests like PCA3 are currently under investigation in order to improve prostate cancer diagnosis and to decrease the rate of unnecessary rebiopsies. PATIENTS AND METHODS: data from the previous prospective European multicentre study were reviewed. Only patients with a PSA level of 2.5-10 ng/mL were included in the present study. In all, 301 patients had complete data. The diagnostic accuracy of the PCA3 score for predicting a positive biopsy outcome was studied using sensitivity, specificity, negative and positive predictive values. The PCA3 performance was evaluated relative to three different subgroups of f/tPSA, as follows: >20% (group 1), 10-20% (group 2) and <10% (group 3). RESULTS: the prostate cancer detection rates were 18.8%, 23.9% and 34.8% in groups 1, 2 and 3, respectively. The area under the receiver operating characteristic curve of the PCA3 score, total PSA and f/tPSA was 0.688, 0.553 and 0.571, respectively. The percentage of men with positive biopsies was 30.6%, 37.0% and 44.4% in those with a PCA3 score of >30, vs 10.3%, 15.5% and 28.6% when the PCA3 score was <30, in groups 1, 2 and 3, respectively. The difference was significant only in groups 1 and 2. In men with a f/tPSA of ≤ 10% the difference in detection rates relative to the PCA3 score was not statistically significant regardless of which PCA3 threshold was used. A high PCA3 score was significantly associated with age, clinical T2 stage and positive biopsy (P < 0.001, 0.013 and <0.001, respectively). In bivariate analysis accounting for the PCA3 score and the f/tPSA, a PCA3 score of >30 was a significant independent predictor of positive biopsies (odds ratio 3.01; 95% confidence interval 1.74-5.23; P < 0.001). CONCLUSIONS: PCA3 remained a better predictor of prostate cancer than f/tPSA. In men with a f/tPSA of >10%, the use of the PCA3 score was highly correlated with the risk of having cancer on re-biopsy, and could prevent unnecessary prostate biopsies if the value is low.

Predictive value of PCA3 in urinary sediments in determining clinico-pathological characteristics of prostate cancer.

PURPOSE: PCA3 urine tests have shown to improve the specificity in prostate cancer (PCa) diagnosis, and have thus the potential to reduce the number of unnecessary prostate biopsies and to predict repeat biopsy outcomes. In this study, PCA3 was correlated with clinical stage, biopsy Gleason score (GS), radical prostatectomy GS, tumor volume, and pathological stage to assess its potential as predictor of PCa aggressiveness. METHODS: In this study, 351 men admitted for prostate biopsies based on serum PSA levels >3 ng/ml, an abnormal DRE, and/or a family history of PCa were included. Post-DRE urinary sediments from 336 men were tested using a transcription-mediated amplification-based PCA3 test, and assay results were correlated with clinical stage and biopsy GS. In a sub-cohort of 70 men who underwent radical prostatectomy, the PCA3 values were correlated to their radical prostatectomy GS, tumor volume, and pathological stage. RESULTS: In this patient cohort we could not find a correlation between clinical stage, biopsy GS, radical prostatectomy GS, tumor volume, and pathological stage. CONCLUSIONS: The predictive value of PCA3 for PCa aggressiveness features as reported in earlier studies cannot be confirmed in our study. Experimental differences (urine sediments vs. whole urine) and cohort may explain this. The exact place of PCA3 as prognostic test for PCa remains the subject of investigation.

Preliminary evaluation of the effect of dutasteride on PCA3 in post-DRE urine sediments: a randomized, open-label, parallel-group pilot study.

BACKGROUND: Dutasteride is commonly used in patients that are also at risk for prostate cancer (PCa). Therefore, the influence of dutasteride on PCa markers has to be studied. To date, only the effect of dutasteride on serum prostate-specific antigen (PSA) has been studied. This was the first study to investigate the effect of dutasteride on the new PCa marker PCA3, longitudinally and in a dose dependent manner. METHODS: From April 25, 2005 to October 31, 2006, 16 subjects with benign prostatic hyperplasia (BPH) and 9 subjects with clinically localized PCa were enrolled at the urological outpatient clinics of one university hospital and one community hospital. Eight subjects with BPH and five with PCa received 0.5 mg dutasteride once daily for 3 months, eight with BPH and four with PCa received 3.5 mg. No subjects were withdrawn because of adverse effects. RESULTS: In all four groups both 0.5 and 3.5 mg dutasteride had a variable effect on the PCA3 score. In contrast, its other effects were consistent as it rapidly reduced serum DHT by >or=90%, over time increased serum T by 20-30%, over time halved serum PSA and decreased prostate volume by 10-16%. CONCLUSIONS: In this exploratory/pilot study the effect of dutasteride on the PCA3 score was variable. This should be taken into account while using PCA3 in diagnostics. As this study was exploratory, the influence of androgen-deprivation therapy on the PCA3 score should be analyzed further.

Prostate cancer gene 3 (PCA3): development and internal validation of a novel biopsy nomogram.

BACKGROUND: Urinary prostate cancer gene 3 (PCA3) represents a promising novel marker of prostate cancer detection. OBJECTIVE: To test whether urinary PCA3 assay improves prostate cancer (PCa) risk assessment and to construct a decision-making aid in a multi-institutional cohort with pre-prostate biopsy data. DESIGN, SETTING, AND PARTICIPANTS: PCA3 assay cut-off threshold analyses were followed by logistic regression models which used established predictors to assess PCa-risk at biopsy in a large multi-institutional data set of 809 men at risk of harboring PCa. MEASUREMENTS: Regression coefficients were used to construct four sets of nomograms. Predictive accuracy (PA) estimates of biopsy outcome predictions were quantified using the area under the curve of the receiver operator characteristic analysis in models with and without PCA3. Bootstrap resamples were used for internal validation and to reduce overfit bias. The extent of overestimation or underestimation of the observed PCa rate at biopsy was explored graphically using nonparametric loss-calibration plots. Differences in PA were tested using the Mantel-Haenszel test. Finally, nomogram-derived probability cut-offs were tested to assess the ability to identify patients with or without PCa. RESULTS AND LIMITATIONS: PCA3 was identified as a statistically independent risk factor of PCa at biopsy. Addition of a PCA3 assay improved bootstrap-corrected multivariate PA of the base model between 2% and 5%. The highest increment in PA resulted from a PCA3 assay cut-off threshold of 17, where a 5% gain in PA (from 0.68 to 0.73, p=0.04) was recorded. Nomogram probability-derived risk cut-off analyses further corroborate the superiority of the PCA3 nomogram over the base model. CONCLUSIONS: PCA3 fulfills the criteria for a novel marker capable of increasing PA of multivariate biopsy models. This novel PCA3-based nomogram better identifies men at risk of harboring PCa and assists in deciding whether further evaluation is necessary.

Clinical utility of the PCA3 urine assay in European men scheduled for repeat biopsy.

BACKGROUND: The Prostate CAncer gene 3 (PCA3) assay has shown promise as an aid in prostate cancer (pCA) diagnosis in identifying men with a high probability of a positive (repeat) biopsy. OBJECTIVE: This study evaluated the clinical utility of the PROGENSA PCA3 assay. DESIGN, SETTING, AND PARTICIPANTS: This European prospective, multicentre study enrolled men with one or two negative biopsies scheduled for repeat biopsy. MEASUREMENTS: After digital rectal examination (DRE), first-catch urine was collected to measure PCA3 mRNA concentration and to calculate the PCA3 score. The PCA3 score was compared to biopsy outcome. The diagnostic accuracy of the PCA3 assay was compared to percent of free prostate-specific antigen (%fPSA). RESULTS AND LIMITATIONS: In 463 men, the positive repeat biopsy rate was 28%. The higher the PCA3 score, the greater the probability of a positive repeat biopsy. The PCA3 score (cut-off of 35) had a greater diagnostic accuracy than %fPSA (cut-off of 25%). The PCA3 score was independent of the number of previous biopsies, age, prostate volume, and total prostate-specific antigen (PSA) level. Moreover, the PCA3 score was significantly higher in men with high-grade prostate intraepithelial neoplasia (HGPIN) versus those without HGPIN, clinical stage T2 versus T1, Gleason score >or=7 versus <7, and "significant" versus "indolent" (clinical stage T1c, PSA density [PSAD] <0.15ng/ml, Gleason score in biopsy

Detailed analysis of histopathological parameters in radical prostatectomy specimens and PCA3 urine test results.

BACKGROUND: Due to the drawbacks of serum prostate-specific antigen, there is an ongoing search for new diagnostic and prognostic prostate cancer (PCa) markers. PCA3 has proven to be of value in the diagnosis of PCa. However, so far few attempts have been made to investigate the prognostic value of PCA3. Our objective was to further investigate the prognostic value of PCA3. METHODS: In this study we correlated the PCA3 score in urinary sediments after digital rectal examination in 62 men with the classical prognostic parameters assessed in radical prostatectomy specimens (i.e. Gleason score, pathological tumor stage and total tumor volume) and moreover, with the expression of three immunohistochemical markers for PCa biological aggressiveness (i.e. E-cadherin, alpha-catenin and EZH2). The results from this study serve as a reflection on and a valuable adjunct to recently published results. RESULTS: We did not find a significant correlation of the PCA3 score with the classical prognostic parameters assessed in radical prostatectomy specimens or the expression of the immunohistochemical markers for PCa biological aggressiveness. However, we did observe a trend for a higher PCA3 score in significant PCa versus insignificant PCa, aberrant E-cadherin staining versus normal E-cadherin staining and increased EZH2 staining versus normal EZH2 staining. CONCLUSIONS: In this study we could not prove the prognostic value of PCA3. Further research with large numbers of men and adequate follow-up is needed to provide a definitive answer to the question if PCA3 is not only a diagnostic but also a prognostic PCa marker.

Molecular PCA3 diagnostics on prostatic fluid.

BACKGROUND: The PCA3 test on urine can improve specificity in prostate cancer (PCa) diagnosis and could prevent unnecessary prostate biopsies. In this study, we evaluated the PCA3 test on prostatic fluid and compared this with the PCA3 test on urine in a clinical research setting. METHODS: Prostatic fluid and urine samples from 67 men were collected following digital rectal examination (DRE). The sediments were analyzed using the quantitative APTIMA PCA3 test. The results were compared with prostate biopsy results. RESULTS: Using a PCA3 score of 66 as a cut-off value, the test on prostatic fluid had 65% sensitivity for the detection of PCa, 82% specificity and a negative predictive value of 82%. At a cut-off value of 43, the test on urine had 61% sensitivity, 80% specificity and a negative predictive value of 80%. CONCLUSIONS: The PCA3 test can be performed on both urine and prostatic fluid in the diagnosis of PCa with comparable results.

The time-resolved fluorescence-based PCA3 test on urinary sediments after digital rectal examination; a Dutch multicenter validation of the diagnostic performance.

PURPOSE: To improve the specificity in prostate cancer diagnosis and to prevent unnecessary prostate biopsies, especially in the serum prostate-specific antigen (PSA) "gray zone" between 3 and 15 ng/mL, the implementation of prostate cancer-specific markers is urgently needed. The recently discovered prostate cancer antigen 3 (PCA3) is such a promising prostate cancer marker. In a previous single institution study, the PCA3 urine test clearly proved to be of diagnostic value. Therefore, the diagnostic performance of the PCA3 urine test was validated in a multicenter study. EXPERIMENTAL DESIGN: The first voided urine after digital rectal examination was collected from a total of 583 men with serum PSA levels between 3 and 15 ng/mL who were to undergo prostate biopsies. We determined the PCA3 score in these samples and correlated the results with the results of the prostate biopsies. RESULTS: A total of 534 men (92%) had an informative sample. The area under the receiver-operating characteristic curve, a measure of the diagnostic accuracy of a test, was 0.66 for the PCA3 urine test and 0.57 for serum PSA. The sensitivity for the PCA3 urine test was 65%, the specificity was 66% (versus 47% for serum PSA), and the negative predictive value was 80%. CONCLUSIONS: In this multicenter study, we validated the diagnostic performance of the PCA3 urine test in the largest group studied thus far using a PCA3 gene-based test. This study shows that the PCA3 urine test, when used as a reflex test, can improve the specificity in prostate cancer diagnosis and could prevent many unnecessary prostate biopsies.