Cost-effectiveness of an urinary biomarker panel in combination with MRI for prostate cancer diagnosis.

PURPOSE: The health impact and cost-effectiveness of the biomarker test SelectMDx were evaluated when used in combination with MRI, in two US populations: biopsy naïve men and men with a previous negative biopsy. METHODS: Using a decision model, the current MRI strategy was compared with two SelectMDx strategies: SelectMDx used before MRI to select men for MRI and SelectMDx used after a negative MRI to select men for biopsy. Parameters were informed by the literature most relevant for both populations. Differences in quality-adjusted life years (QALYs) and costs between the current strategy and the SelectMDx strategies were calculated using two different assumptions regarding PCa-specific mortality (SPCG-4 and PIVOT). RESULTS: In biopsy naïve men, the use of SelectMDx before MRI results in a gain of 0.004 QALY per patient under the SPCG-4 scenario, and a gain of 0.030 QALY under the PIVOT scenario. The cost savings are $1650 per patient. When used after MRI, SelectMDx results in a QALY gain per patient of 0.004 (SPCG-4), and 0.006 (PIVOT) with $262 in cost savings. In the previous negative population, SelectMDx before MRI results in a QALY gain of 0.006 (SPCG-4) and 0.022 (PIVOT), with $1281 in cost savings per patient. SelectMDx after MRI results in a QALY gain of 0.003 (SPCG-4) and 0.004 (PIVOT) with $193 in cost savings. CONCLUSION: Application of SelectMDx results in better health outcomes and cost savings. The value of SelectMDx was highest when used before MRI to select patients for MRI and subsequent biopsy.

Validation of a 2-gene mRNA urine test for the detection of ≥GG2 prostate cancer in an opportunistic screening population.

BACKGROUND: A 2-gene urine-based molecular test that targets messenger RNAs known to be overexpressed in aggressive prostate cancer (PCa) has been described as a helpful method for detecting clinically significant prostate cancer (grade group [GG] ≥2). We performed an external validation of this test in men undergoing initial prostate biopsy (Bx) within a Spanish opportunistic screening scenario. METHODS: We analyzed archived samples from 492 men who underwent prostate Bx in an opportunistic screening scenario, with prostate-specific antigen (PSA) 3 to 10 ng/mL and/or suspicious digital rectal exploration (DRE) and without previous multi-parametric magnetic resonance imaging (mpMRI). Urinary biomarker measurements were combined with clinical risk factors to determine a risk score, and accuracy for GG ≥ 2 PCa detection was compared with PCA3, European randomized screening in prostate cancer (ERSPC), and prostate biopsy collaborative group (PBCG) risk calculators in a validation workup that included calibration, discrimination, and clinical utility analysis. RESULTS: In our cohort, the detection rates for GG1 and GG ≥ 2 PCa were 20.3% and 14.0%, respectively. The median PSA level was 3.9 ng/mL and 13.4% of subjects had suspicious DRE findings. The median risk score for men with GG ≥ 2 PCa was 21 (interquartile range: 14-28), significantly higher than benign+GG1 PCa (10, 6-18), P < .001, achieving the highest area under the curve among the models tested, 0.749 (95% confidence interval: 0.690-0.807). The urine test was well-calibrated, while ERSPC showed a slight underestimation and PBCG a slight overestimation of risk. Assuming a GG2 non-detection rate of 11% without using mpMRI, use of the urinary biomarker-based clinical model could have helped avoid 37.2% of excess biopsies while delaying the diagnosis of eight patients (1.6% of the entire cohort) with GG ≥ 2 PCa. CONCLUSIONS: In this first evaluation in an opportunistic screening population, the urinary biomarker-based test improved the detection of clinically significant PCa. Facing men with elevated PSA and/or suspicious DRE, it could be a useful tool to help avoid excess initial Bx and to identify patients most likely to benefit from Bx.

Multicenter Optimization and Validation of a 2-Gene mRNA Urine Test for Detection of Clinically Significant Prostate Cancer before Initial Prostate Biopsy.

PURPOSE: A 2-gene, urine based molecular test that combines mRNA biomarkers with clinical factors can risk stratify patients for clinically significant prostate cancer. To ensure the generalizability of assay results we optimized and validated the clinical model for men with serum prostate specific antigen less than 10 ng/ml who were undergoing initial prostate biopsy. MATERIALS AND METHODS: Urine samples were collected from 1,955 men from The Netherlands, France and Germany prior to an initial prostate biopsy and study subjects were divided into training and validation cohorts. Urinary HOXC6 and DLX1 mRNA levels were quantified and RNA results were then combined with other risk factors in a clinical model optimized to detect ISUP (International Society of Urological Pathology) Grade Group 2 or greater prostate cancer in men with prostate specific antigen less than 10 ng/ml. Results in the validation cohort were compared with the PCPTRC (Prostate Cancer Prevention Trial Risk Calculator), version 2.0. RESULTS: The optimal clinical model included urinary HOXC6 and DLX1 mRNA levels, patient age, digital rectal examination and prostate specific antigen density (serum prostate specific antigen/prostate volume). In the 715 validation cohort subjects with prostate specific antigen less than 10 ng/ml the AUC was 0.82 with 89% sensitivity, 53% specificity and 95% negative predictive value. The PCPTRC AUC was 0.70. The full validation cohort of 916 men including all prostate specific antigen levels yielded an AUC of 0.85 with 93% sensitivity, 47% specificity and 95% negative predictive value. The PCPTRC AUC was 0.76. CONCLUSIONS: The 2-gene based urine assay, which is optimized for biopsy naïve patients with serum prostate specific antigen less than 10 ng/ml, demonstrated high sensitivity and negative predictive value to detect clinically significant prostate cancer. These data support using the test to help guide initial prostate biopsy decisions.

Epigenetic risk score improves prostate cancer risk assessment.

BACKGROUND: Early detection of aggressive prostate cancer (PCa) remains crucial for effective treatment of patients. However, PCa screening remains controversial due to a high rate of overdiagnosis and overtreatment. To better reconcile both objectives, more effective methods for assessing disease severity at the time of diagnosis are needed. METHODS: The relationship between DNA-methylation and high-grade PCa was examined in a cohort of 102 prospectively enrolled men who received standard 12-core prostate biopsies. EpiScore, an algorithm that quantifies the relative DNA methylation intensities of GSTP1, RASSF1, and APC in prostate biopsy tissue, was evaluated as a method to compensate for biopsy under-sampling and improve risk stratification at the time of diagnosis. RESULTS: DNA-methylation intensities of GSTP1, RASSF1, and APC were higher in biopsy cores from men diagnosed with GS ≥ 7 cancer compared to men with diagnosed GS 6 disease. This was confirmed by EpiScore, which was significantly higher for subjects with high-grade biopsies and higher NCCN risk categories (both P < 0.001). In patients diagnosed with GS ≥ 7, increased levels of DNA-methylation were present, not only in the high-grade biopsy cores, but also in other cores with no or low-grade disease (P < 0.001). By combining EpiScore with traditional clinical risk factors into a logistic regression model, the prediction of high GS reached an AUC of 0.82 (95%CI: 0.73-0.91) with EpiScore, DRE, and atypical histological findings as most important contributors. CONCLUSIONS: In men diagnosed with PCa, DNA-methylation profiling can detect under-sampled high-risk PCa in prostate biopsy specimens through a field effect. Predictive accuracy increased when EpiScore was combined with other clinical risk factors. These results suggest that EpiScore could aid in the detection of occult high-grade disease at the time of diagnosis, thereby improving the selection of candidates for Active Surveillance.

Phase II study of cytarabine in men with docetaxel-refractory, castration-resistant prostate cancer with evaluation of TMPRSS2-ERG and SPINK1 as serum biomarkers.

UNLABELLED: What's known on the subject? and What does the study add? To date, there has been limited impetus to examine the use of cytarabine in prostate cancer. We presented preliminary laboratory data to suggest its utility in the castration refractory prostate cancer (CRPC) population which, combined with a previous case report, suggested it may have hitherto unrecognized utility in this setting. Embedded in this study was peripheral blood sampling for TMPRSS2-ERG and SPINK1, two genes that are believed to define prostate cancer genotypes, to assess their utility as biomarkers This study suggests that at the delivered doses, cytarabine has limited efficacy and significant myelotoxicity suggesting, it does not have a role in the treatment of docetaxel-refractory CRPC. The presence of serum TMPRSS2-ERG and SPINK1 mRNA biomarkers recovered from blood suggest that their analysis is worthy of further study. OBJECTIVES: To run a phase II clinical trial of cytarabine in men with docetaxel-refractory, castration-resistant prostate cancer (CRPC), based on evidence that cytarabine might be effective in men with abnormalities of ERG oncogenes. To measure mRNA levels of prostate cancer-related genes in blood as biomarkers. PATIENTS AND METHODS: Ten of a planned maximum of 30 men received i.v. cytarabine at doses of 0.25-1g/m(2) at 21-day intervals. The primary endpoint was prostate-specific antigen (PSA) response. Archival tumour samples were assessed by fluorescence in-situ hybridization for TMPRSS2:ERG translocation, and by immunohistochemistry for serine peptidase inhibitor Kazal type 1 (SPINK1). Blood was processed for mRNA quantification of TMPRSS2:ERG (exon1:exon4), SPINK1 and PSA. RESULTS: A PSA response was not observed in any patient. The trial was stopped at the end of stage 1 of a modified Flemming design. The median number of cycles administered was 3. Grade 3-4 haematological toxicity was common. Five patients were subsequently excluded from the study for toxicity, and five for disease progression. Analysis of whole blood mRNA for T1:E4 translocation in TMPRSS2:ERG was consistent with that in the tumour in 8/9 evaluable cases (one was concordantly positive, seven were concordantly negative), SPINK1 results were concordant in 9/10 cases (two were concordantly positive, seven were concordantly negative [P = 0.047 for the predictive value]). There was no correlation between PSA or SPINK protein and their respective mRNA copy levels in blood. CONCLUSIONS: Cytarabine at the doses used is ineffective for men with CRPC. Blood mRNA levels of prostate cancer genes may represent a novel aspect of monitoring prostate cancer and have implications for the understanding of tumour-derived mRNA.

Association of Urinary MyProstateScore, Age, and Prostate Volume in a Longitudinal Cohort of Healthy Men: Long-term Findings from the Olmsted County Study.

BACKGROUND: Serum prostate-specific antigen (PSA), used in prostate cancer screening, is nonspecific for cancer and is affected by age and prostate volume. More specific biomarkers could be more accurate for early detection of prostate cancer and reduce unnecessary prostate biopsies. OBJECTIVE: To evaluate the association of age and prostate volume with urinary MyProstateScore (MPS) in a screened, longitudinal cohort without evidence of prostate cancer. DESIGN SETTING AND PARTICIPANTS: The Olmsted County Study included men aged 40-79 yr who underwent biennial prostate cancer screening. PSA ≥4.0 ng/ml or abnormal rectal examination triggered prostate biopsy, and patients with cancer were excluded. The remaining men submitted urinary specimens for PCA3 and TMPRSS2:ERG testing. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: MPS was calculated using the validated, locked model for grade group ≥2 cancer that includes serum PSA, urinary PCA3, and urinary TMPRSS2:ERG. The associations of age and volume with biomarkers were assessed in multivariable regression models. The t statistic was used to quantify the strength of associations independent of the unit of measurement, and R 2 values were used to estimate the proportion of biomarker variance explained by each factor. RESULTS AND LIMITATIONS: The study included 314 screened men without evidence of cancer. In multivariable models including age and volume, PCA3 score was significantly associated with age (t = 7.51; p < 0.001), while T2:ERG score was not associated with age or volume. MPS was significantly associated with both age (t = 7.45; p < 0.001) and volume (t = 3.56; p < 0.001), but accounting for age alone explained the variability observed (R 2 = 0.29) in a similar way to the model including age and volume (R 2 = 0.31). The variability of PCA3, T2:ERG, and MPS was less dependent on age and volume than the variability for PSA (R 2 = 0.45). CONCLUSIONS: In a cohort of longitudinally screened men without evidence of cancer, we found that MPS demonstrated less variability with noncancer factors (age, prostate volume) than PSA did. These findings support the biology of these markers as more cancer-specific than PSA and highlight their promise in reducing the morbidity associated with PSA-based screening. PATIENT SUMMARY: In a group of men with no evidence of prostate cancer, we found that each of three urine-based markers of cancer-PCA3, T2:ERG, and the commercially available MyProstateScore test-showed less variability with noncancer factors (age and prostate volume) than serum PSA (prostate-specific antigen) did. These findings support their proposed use as noninvasive markers of prostate cancer that could improve the accuracy of early detection.

Molecular assays for the detection of prostate tumor derived nucleic acids in peripheral blood.

BACKGROUND: Prostate cancer is the second leading cause of cancer mortality in American men. Although serum PSA testing is widely used for early detection, more specific prognostic tests are needed to guide treatment decisions. Recently, the enumeration of circulating prostate epithelial cells has been shown to correlate with disease recurrence and metastasis following definitive treatment. The purpose of our study was to investigate an immunomagnetic fractionation procedure to enrich circulating prostate tumor cells (CTCs) from peripheral blood specimens, and to apply amplified molecular assays for the detection of prostate-specific markers (PSA, PCA3 and TMPRSS2:ERG gene fusion mRNAs). RESULTS: As few as five prostate cancer cells were detected per 5 mL of whole blood in model system experiments using anti-EpCAM magnetic particles alone or in combination with anti-PSMA magnetic particles. In our experiments, anti-EpCAM magnetic particles alone exhibited equivalent or better analytical performance with patient samples compared to a combination of anti-EpCAM + anti-PSMA magnetic particles. Up to 39% of men with advanced prostate cancer tested positive with one or more of the molecular assays tested, whereas control samples from men with benign prostate hyperplasia gave consistently negative results as expected. Interestingly, for the vast majority of men who tested positive for PSA mRNA following CTC enrichment, their matched plasma samples also tested positive, although CTC enrichment gave higher overall mRNA copy numbers. CONCLUSION: CTCs were successfully enriched and detected in men with advanced prostate cancer using an immunomagnetic enrichment procedure coupled with amplified molecular assays for PSA, PCA3, and TMPRSS2:ERG gene fusion mRNAs. Our results indicate that men who test positive following CTC enrichment also exhibit higher detectable levels of non-cellular, circulating prostate-specific mRNAs.

PCA3 molecular urine test for predicting repeat prostate biopsy outcome in populations at risk: validation in the placebo arm of the dutasteride REDUCE trial.

PURPOSE: We determined the performance of PCA3 alone and in the presence of other covariates as an indicator of contemporaneous and future prostate biopsy results in a population with previous negative biopsy and increased serum prostate specific antigen. MATERIALS AND METHODS: Urine PCA3 scores were determined before year 2 and year 4 biopsies from patients in the placebo arm of the REDUCE trial, a prostate cancer risk reduction study evaluating men with moderately increased serum prostate specific antigen results and negative biopsy at baseline. PCA3, serum prostate specific antigen and percent free prostate specific antigen results were correlated with biopsy outcome via univariate logistic regression and ROC analyses. Multivariate logistic regression was also performed including these biomarkers together with prostate volume, age and family history. RESULTS: PCA3 scores were measurable from 1,072 of 1,140 subjects (94% informative rate). PCA3 scores were associated with positive biopsy rate (p <0.0001) and correlated with biopsy Gleason score (p = 0.0017). PCA3 AUC of 0.693 was greater than serum prostate specific antigen (0.612, p = 0.0077 vs PCA3). The multivariate logistic regression model yielded an AUC of 0.753 and exclusion of PCA3 from the model decreased AUC to 0.717 (p = 0.0009). PCA3 at year 2 was a significant predictor of year 4 biopsy outcome (AUC 0.634, p = 0.0002), whereas serum prostate specific antigen and free prostate specific antigen were not predictive (p = 0.3281 and 0.6782, respectively). CONCLUSIONS: PCA3 clinical performance was validated in the largest repeat biopsy study to date. Increased PCA3 scores indicated increased risk of contemporaneous cancers and predicted future biopsy outcomes. Use of PCA3 in combination with serum prostate specific antigen and other risk factors significantly increased diagnostic accuracy.

Urinary Molecular Biomarker Test Impacts Prostate Biopsy Decision Making in Clinical Practice.

INTRODUCTION: There is an unmet need for noninvasive methods to better identify patients at increased risk for clinically significant prostate cancer. SelectMDx® is a molecular urine test validated for the detection of Gleason score 7 and higher cancers (ISUP [International Society of Urological Pathology] Grade Group 2-5). In this multicenter trial we evaluated the test's impact on prostate biopsy decision making in clinical practice. METHODS: The study involved 5 U.S. community urology practices which sequentially enrolled 418 patients who received a SelectMDx test between May 2016 and April 2017 while undergoing evaluation for initial prostate biopsy. All tests were ordered by the urologist for patient management. We determined biopsy and prostate cancer detection rates in patients with SelectMDx positive versus SelectMDx negative results. RESULTS: Of the 418 subjects evaluated with SelectMDx 253 (61%) had negative results and 165 (39%) had positive results. Subsequent biopsy rates for SelectMDx positive and negative cases were 60% (99) and 12% (32), respectively (p <0.001). Time from SelectMDx result to biopsy was shorter for those with positive vs negative results (median 2 vs 5 months, p=0.001). Of patients who underwent biopsy within 3 months of testing 71 (43%) with positive results underwent biopsy and 27 had cancers identified, including 10 greater than Grade Group 2. Of 9 patients with SelectMDx negative results (3.6%) who underwent biopsy 4 were diagnosed with cancer, all Grade Group 2 or less. CONCLUSIONS: SelectMDx had a significant impact on initial prostate biopsy decision making. Biopsy rates in SelectMDx positive cases were fivefold higher than in SelectMDx negative cases. These results describe the clinical utility of SelectMDx in real-world community urology practice.

Evaluation of an Epigenetic Assay for Predicting Repeat Prostate Biopsy Outcome in African American Men.

OBJECTIVE: To evaluate an epigenetic assay performed on tissue from negative prostate biopsies in a group of African American (AA) men undergoing repeat biopsy, and to compare accuracy for predicting repeat biopsy outcome to prior studies conducted in predominantly Caucasian populations. MATERIALS AND METHODS: The study population consisted of 211 AA men from 7 urology centers across the United States; all of whom were undergoing 12-core transrectal ultrasound-guided repeat biopsy within 30 months from a negative index biopsy. All biopsy cores from the negative index biopsy were profiled for the epigenetic biomarkers GSTP1, APC, and RASSF1 using ConfirmMDx for Prostate Cancer (MDxHealth, Irvine, CA). RESULTS: Upon repeat biopsy, 130 of 211 subjects (62%) had no prostate cancer (PCa) detected and 81 of 211 (38%) were diagnosed with PCa. Of the subjects with PCa, 54 (67%) were diagnosed with Gleason score (GS) ≤6 PCa and 27 (33%) with GS ≥7 disease. For detection of PCa at repeat biopsy, ConfirmMDx sensitivity was 74.1% and specificity was 60.0%, equivalent to prior studies (P = .235 and .697, respectively). For detection of GS ≥7 PCa, sensitivity was 78% and specificity was 53%. The negative predictive values for detection of all PCa and GS ≥7 PCa were 78.8% and 94.2%, respectively. CONCLUSION: In this group of AA men, we successfully validated an epigenetic assay to assess the need for repeat biopsy. Results were consistent with previous studies from predominantly Caucasian populations. Therefore, the ConfirmMDx assay is a useful tool for risk stratification of AA men who had an initial negative biopsy.

PCA3 molecular urine assay correlates with prostate cancer tumor volume: implication in selecting candidates for active surveillance.

PURPOSE: Prostate cancer gene 3 (PCA3) has shown promise as a molecular marker in prostate cancer detection. We assessed the association of urinary PCA3 score with prostatectomy tumor volume and other clinical and pathological features. MATERIALS AND METHODS: Urine specimens were collected after digital rectal examination from 59 men scheduled for prostate biopsy and 83 men scheduled for radical prostatectomy. Prostatectomy findings were evaluable for 96 men. PCA3 and prostate specific antigen mRNAs were quantified with Gen-Probe DTS 400 System. The PCA3 score was defined as the ratio of PCA3 mRNA/prostate specific antigen mRNA x10(3). RESULTS: The PCA3 score in men with negative biopsies (30) and positive biopsies (29) were significantly different (median 21.1 and 31.0, respectively, p = 0.029). The PCA3 score was significantly correlated with total tumor volume in prostatectomy specimens (r = 0.269, p = 0.008), and was also associated with prostatectomy Gleason score (6 vs 7 or greater, p = 0.005) but not with other clinical and pathological features. The PCA3 score was significantly different when comparing low volume/low grade cancer (dominant tumor volume less than 0.5 cc, Gleason score 6) and significant cancer (p = 0.007). On multivariate analysis PCA3 was the best predictor of total tumor volume in prostatectomy (p = 0.001). Receiver operating characteristic curve analysis showed that the PCA3 score could discriminate low volume cancer (total tumor volume less than 0.5 cc) well with area under the curve of 0.757. CONCLUSIONS: The PCA3 score appears to stratify men based on prostatectomy tumor volume and Gleason score, and may have clinical applicability in selecting men who have low volume/low grade cancer.

Predicting prostate cancer risk through incorporation of prostate cancer gene 3.

PURPOSE: The online Prostate Cancer Prevention Trial risk calculator combines prostate specific antigen, digital rectal examination, family and biopsy history, age and race to determine the risk of prostate cancer. In this report we incorporate the biomarker prostate cancer gene 3 into the Prostate Cancer Prevention Trial risk calculator. MATERIALS AND METHODS: Methodology was developed to incorporate new markers for prostate cancer into the Prostate Cancer Prevention Trial risk calculator based on likelihood ratios calculated from separate case control or cohort studies. The methodology was applied to incorporate the marker prostate cancer gene 3 into the risk calculator based on a cohort of 521 men who underwent prostate biopsy with measurements of urinary prostate cancer gene 3, serum prostate specific antigen, digital rectal examination and biopsy history. External validation of the updated risk calculator was performed on a cohort of 443 European patients, and compared to Prostate Cancer Prevention Trial risks, prostate specific antigen and prostate cancer gene 3 by area underneath the receiver operating characteristic curve, sensitivity and specificity. RESULTS: The AUC of posterior risks (AUC 0.696, 95% CI 0.641-0.750) was higher than that of prostate specific antigen (AUC 0.607, 95% CI 0.546-0.668, p = 0.001) and Prostate Cancer Prevention Trial risks (AUC 0.653, 95% CI 0.593-0.714, p <0.05). Although it was higher it was not statistically significantly different from that of prostate cancer gene 3 (AUC 0.665, 95% CI 0.610-0.721, p >0.05). Sensitivities of posterior risks were higher than those of prostate cancer gene 3, prostate specific antigen and Prostate Cancer Prevention Trial risks. CONCLUSIONS: New markers for prostate cancer can be incorporated into the Prostate Cancer Prevention Trial risk calculator by a novel approach. Incorporation of prostate cancer gene 3 improved the diagnostic accuracy of the Prostate Cancer Prevention Trial risk calculator.

PCA3: a molecular urine assay for predicting prostate biopsy outcome.

PURPOSE: A urinary assay for PCA3, an mRNA that is highly over expressed in prostate cancer cells, has shown usefulness as a diagnostic test for this common malignancy. We further characterized PCA3 performance in different groups of men and determined whether the PCA3 score could synergize with other clinical information to predict biopsy outcome. MATERIALS AND METHODS: Prospectively urine was collected following standardized digital rectal examination in 570 men immediately before prostate biopsy. Urinary PCA3 mRNA levels were quantified and then normalized to the amount of prostate derived RNA to generate a PCA3 score. RESULTS: The percent of biopsy positive men identified increased directly with the PCA3 score. PCA3 assay performance was equivalent in the first vs previous negative biopsy groups with an area under the ROC curve of 0.70 and 0.68, respectively. Unlike serum prostate specific antigen the PCA3 score did not increase with prostate volume. PCA3 assay sensitivity and specificity were equivalent at serum prostate specific antigen less than 4, 4 to 10 and more than 10 ng/ml. A logistic regression algorithm using PCA3, serum prostate specific antigen, prostate volume and digital rectal examination result increased the AUC from 0.69 for PCA3 alone to 0.75 (p = 0.0002). CONCLUSIONS: PCA3 is independent of prostate volume, serum prostate specific antigen level and the number of prior biopsies. The quantitative PCA3 score correlated with the probability of positive biopsy. Logistic regression results suggest that the PCA3 score could be incorporated into a nomogram for improved prediction of biopsy outcome. The results of this study provide further evidence that PCA3 is a useful adjunct to current methods for prostate cancer diagnosis.

PCA3 score before radical prostatectomy predicts extracapsular extension and tumor volume.

PURPOSE: PCA3 is a prostate specific, nonprotein coding RNA that is over expressed in prostate cancer. Recent studies showed the diagnostic potential of a urine based PCA3 for predicting biopsy outcome. We assessed the relationship between urine PCA3 and pathological features in whole mount radical prostatectomy specimens. MATERIALS AND METHODS: Post-digital rectal examination urine specimens were obtained from 72 men with prostate cancer before radical prostatectomy. PCA3 and PSA mRNA were measured. The ratio of PCA3 to PSA mRNA was recorded as a PCA3 score and correlated with data on each prostate specimen. RESULTS: Patients with extracapsular extension had a significantly higher median PCA3 score than patients without extracapsular extension (48.8 vs 18.7, p = 0.02). PCA3 score significantly correlated with total tumor volume (r = 0.38, p <0.01). On multivariate analysis PCA3 score was an independent predictor of extracapsular extension (p = 0.01) and total tumor volume less than 0.5 cc (p = 0.04). At a cutoff PCA3 score of 47 extracapsular extension was predicted with 94% specificity and an 80% positive predictive value. When combined with serum PSA and biopsy Gleason score, the ROC AUC for predicting extracapsular extension was 0.90. CONCLUSIONS: PCA3 detected in the post-digital rectal examination urine of patients with prostate cancer correlated with pathological findings. Therefore, it could provide prognostic information. To our knowledge this is the first report of a molecular urine assay that predicts extracapsular extension.

A multicenter evaluation of the PCA3 molecular urine test: pre-analytical effects, analytical performance, and diagnostic accuracy.

BACKGROUND: Measurement of prostate cancer gene 3 (PCA3) mRNA normalized to prostate-specific antigen (PSA) mRNA in urine has been proposed as a marker for prostate cancer. METHODS: We investigated pre-analytical effects, analytical performance, and diagnostic accuracy of a quantitative assay for PCA3. RESULTS: Urine specimens collected without prostate manipulation demonstrated low informative rates. However, specimens collected following digital rectal examinations of 3 or 8 strokes per prostate lobe demonstrated informative rates >94%. Across all urine specimen types, median PCA3 results did not show statistically significant differences (P>0.8). Measurements of controls of known mRNA content demonstrated percent recoveries of 100+/-15% for both PCA3 and PSA mRNAs. PCA3 mRNA total, intra-assay, inter-assay, and inter-site CVs were < or =17.1%, < or =14.0%, < or =9.9%, and < or =3.2%, respectively. Corresponding CVs for PSA mRNA assay were < or =11.5%, < or =8.6%, < or =7.9%, and < or =8.3%. Blinded assay of urines from 72 men with known prostate biopsy outcomes yielded areas under the curve from receiver-operating characteristic analysis of 0.7 at both research sites. Deming regression of individual PCA3 results between sites yielded slope=0.94, intercept=0.48, R=0.9677 (P<0.0001). CONCLUSIONS: The PCA3 assay is insensitive to pre-analytical factors, performs well analytically and correctly classifies a high percent of subjects with known prostate cancer status across research sites.

Molecular markers for prostate cancer.

Serum PSA testing has been used for over 20 years as an aid in the diagnosis and management of prostate cancer. Although highly sensitive, it suffers from a lack of specificity, showing elevated serum levels in a variety of other conditions including prostatitis, benign prostate hyperplasia, and non-cancerous neoplasia. During this period, numerous serum protein analytes have been investigated as alternative and/or supplemental tests for PSA, however in general these analytes have likewise suffered from a lack of specificity, often showing serum elevations in other clinical presentations. More recently, molecular assays targeting prostate disease at the DNA or RNA level have been investigated for potential diagnostic and prognostic utility. With the aid of modern genomics technologies, a variety of molecular biomarkers have been discovered that show potential for specific correlation with prostate cancer. Much of this discovery has been retrospective, using microdissected tissue from prostatectomy. The goal of current research is to apply genomic assays to noninvasive specimens such as blood and urine. Progress in this area is the subject of this review.

Association Between Combined TMPRSS2:ERG and PCA3 RNA Urinary Testing and Detection of Aggressive Prostate Cancer.

IMPORTANCE: Potential survival benefits from treating aggressive (Gleason score, ≥7) early-stage prostate cancer are undermined by harms from unnecessary prostate biopsy and overdiagnosis of indolent disease. OBJECTIVE: To evaluate the a priori primary hypothesis that combined measurement of PCA3 and TMPRSS2:ERG (T2:ERG) RNA in the urine after digital rectal examination would improve specificity over measurement of prostate-specific antigen alone for detecting cancer with Gleason score of 7 or higher. As a secondary objective, to evaluate the potential effect of such urine RNA testing on health care costs. DESIGN, SETTING, AND PARTICIPANTS: Prospective, multicenter diagnostic evaluation and validation in academic and community-based ambulatory urology clinics. Participants were a referred sample of men presenting for first-time prostate biopsy without preexisting prostate cancer: 516 eligible participants from among 748 prospective cohort participants in the developmental cohort and 561 eligible participants from 928 in the validation cohort. INTERVENTIONS/EXPOSURES: Urinary PCA3 and T2:ERG RNA measurement before prostate biopsy. MAIN OUTCOMES AND MEASURES: Presence of prostate cancer having Gleason score of 7 or higher on prostate biopsy. Pathology testing was blinded to urine assay results. In the developmental cohort, a multiplex decision algorithm was constructed using urine RNA assays to optimize specificity while maintaining 95% sensitivity for predicting aggressive prostate cancer at initial biopsy. Findings were validated in a separate multicenter cohort via prespecified analysis, blinded per prospective-specimen-collection, retrospective-blinded-evaluation (PRoBE) criteria. Cost effects of the urinary testing strategy were evaluated by modeling observed biopsy results and previously reported treatment outcomes. RESULTS: Among the 516 men in the developmental cohort (mean age, 62 years; range, 33-85 years) combining testing of urinary T2:ERG and PCA3 at thresholds that preserved 95% sensitivity for detecting aggressive prostate cancer improved specificity from 18% to 39%. Among the 561 men in the validation cohort (mean age, 62 years; range, 27-86 years), analysis confirmed improvement in specificity (from 17% to 33%; lower bound of 1-sided 95% CI, 0.73%; prespecified 1-sided P = .04), while high sensitivity (93%) was preserved for aggressive prostate cancer detection. Forty-two percent of unnecessary prostate biopsies would have been averted by using the urine assay results to select men for biopsy. Cost analysis suggested that this urinary testing algorithm to restrict prostate biopsy has greater potential cost-benefit in younger men. CONCLUSIONS AND RELEVANCE: Combined urinary testing for T2:ERG and PCA3 can avert unnecessary biopsy while retaining robust sensitivity for detecting aggressive prostate cancer with consequent potential health care cost savings.

Urine TMPRSS2:ERG Plus PCA3 for Individualized Prostate Cancer Risk Assessment.

BACKGROUND: TMPRSS2:ERG (T2:ERG) and prostate cancer antigen 3 (PCA3) are the most advanced urine-based prostate cancer (PCa) early detection biomarkers. OBJECTIVE: Validate logistic regression models, termed Mi-Prostate Score (MiPS), that incorporate serum prostate-specific antigen (PSA; or the multivariate Prostate Cancer Prevention Trial risk calculator version 1.0 [PCPTrc]) and urine T2:ERG and PCA3 scores for predicting PCa and high-grade PCa on biopsy. DESIGN, SETTING, AND PARTICIPANTS: T2:ERG and PCA3 scores were generated using clinical-grade transcription-mediated amplification assays. Pretrained MiPS models were applied to a validation cohort of whole urine samples prospectively collected after digital rectal examination from 1244 men presenting for biopsy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Area under the curve (AUC) was used to compare the performance of serum PSA (or the PCPTrc) alone and MiPS models. Decision curve analysis (DCA) was used to assess clinical benefit. RESULTS AND LIMITATIONS: Among informative validation cohort samples (n=1225 [98%], 80% from patients presenting for initial biopsy), models incorporating T2:ERG had significantly greater AUC than PSA (or PCPTrc) for predicting PCa (PSA: 0.693 vs 0.585; PCPTrc: 0.718 vs 0.639; both p<0.001) or high-grade (Gleason score >6) PCa on biopsy (PSA: 0.729 vs 0.651, p<0.001; PCPTrc: 0.754 vs 0.707, p=0.006). MiPS models incorporating T2:ERG score had significantly greater AUC (all p<0.001) than models incorporating only PCA3 plus PSA (or PCPTrc or high-grade cancer PCPTrc [PCPThg]). DCA demonstrated net benefit of the MiPS_PCPTrc (or MiPS_PCPThg) model compared with the PCPTrc (or PCPThg) across relevant threshold probabilities. CONCLUSIONS: Incorporating urine T2:ERG and PCA3 scores improves the performance of serum PSA (or PCPTrc) for predicting PCa and high-grade PCa on biopsy. PATIENT SUMMARY: Incorporation of two prostate cancer (PCa)-specific biomarkers (TMPRSS2:ERG and PCA3) measured in the urine improved on serum prostate-specific antigen (or a multivariate risk calculator) for predicting the presence of PCa and high-grade PCa on biopsy. A combined test, Mi-Prostate Score, uses models validated in this study and is clinically available to provide individualized risk estimates.

A comparative study of ERG status assessment on DNA, mRNA, and protein levels using unique samples from a Swedish biopsy cohort.

The ERG rearrangement is identified in approximately 50% of prostate cancer screened cohorts and is known to be highly specific. This genetic aberration, most commonly leading to the TMPRSS2-ERG fusion, but also SLC45A3-ERG or NDRG1-ERG fusions, all leading to an overexpression of a truncated ERG protein. Most studies have applied in situ hybridization (FISH) methods or mRNA-based assays to investigate the ERG status. Recently, studies showed that ERG protein levels assessed by ERG antibodies can be used as a surrogate marker for ERG rearrangement. In the current study, we investigate ERG status on a series of diagnostic biopsies using DNA-based, mRNA-based, and protein-based assays. We formally compared 3 assay results (ie, FISH, fusion mRNA, and immunohistochemistry) to identify which method could be most appropriate to use when having limited amount of tissue. ERG rearrangement was found in 56% of the cases. Comparing ERG rearrangement status by FISH with ERG overexpression and TMPRSS2-ERG fusion transcript we found 95.1% (154/162, Fisher exact test 9.50E-36) and 85.2% (138/162, Fisher exact test 7.26E-22) concordance, respectively. We show that the ERG antibody highly correlates with the ERG rearrangement with high sensitivity and specificity. We also identified the most common TMPRSS2-ERG isoform in the majority of ERG rearranged cases. These results provide compelling evidence that the ERG antibody can be used to further investigate the role of ERG in prostate cancer.