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Objective: To evaluate measurement of percentage of free prostate-specific antigen (PSA) in serum to improve the specificity of prostate cancer screening in men with serum PSA levels between 4.1 and 10.0 ng/mL.Design: Retrospective, nonrandomized analysis using a research assay for measuring free PSA in frozen serum from men with a spectrum of prostate sizes and digital rectal examination results.Setting: General community outpatient prostate cancer screening program at a university center.Patients: One hundred thirteen men aged 50 years or older, 99% of whom were white, with serum PSA concentrations of 4.1 to 10.0 ng/mL, including 63 men with histologically confirmed benign prostatic hyperplasia, 30 with prostate cancer with an enlarged gland, and 20 with cancer with a normal-sized gland. All study volunteers had undergone prostatic ultrasonography and biopsy.Main Outcome Measures: Percentage of free PSA in serum and percentage of free PSA cutoff that maintained at least 90% sensitivity for prostate cancer detection.Results: Median percentage of free PSA was 9.2% in men with cancer and a normal-sized gland, 15.9% in men with cancer and an enlarged gland, and 18.8% in men with benign prostatic hyperplasia (P < .001). The percentage of free PSA cutoff was higher in men with an enlarged gland and in those with a palpably benign gland. In men with an enlarged, palpably benign gland, a free PSA cutoff of 23.4% or lower detected at least 90% of cancers and would have eliminated 31.3% of negative biopsies.Conclusions: Measurement of percentage of free serum PSA improves specificity of prostate cancer screening in selected men with elevated total serum PSA levels and can reduce unnecessary prostate biopsies with minimal effects on the cancer detection rate; however, further studies are needed to define optimal cutoffs. Final evaluation of PSA screening also must consider the ability of current treatments to improve the prognosis of screen-detected prostate cancer. [ABSTRACT FROM AUTHOR]

Abstract 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.

Prostate cancer is a common malignancy in men and the worldwide burden of this disease is rising. Lifestyle modifications such as smoking cessation, exercise, and weight control offer opportunities to reduce the risk of developing prostate cancer. Early detection of prostate cancer by prostate-specific antigen (PSA) screening is controversial, but changes in the PSA threshold, frequency of screening, and the use of other biomarkers have the potential to minimise the overdiagnosis associated with PSA screening. Several new biomarkers for individuals with raised PSA concentrations or those diagnosed with prostate cancer are likely to identify individuals who can be spared aggressive treatment. Several pharmacological agents such as 5α-reductase inhibitors and aspirin could prevent development of prostate cancer. In this Review, we discuss the present evidence and research questions regarding prevention, early detection of prostate cancer, and management of men either at high risk of prostate cancer or diagnosed with low-grade prostate cancer., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

PSA screening reduces PCa-mortality but the disadvantages overdiagnosis and overtreatment require multivariable risk-prediction tools to select appropriate treatment or active surveillance. This review explains the differences between the two largest screening trials and discusses the drawbacks of screening and its meta-analysisxs. The current American and European screening strategies are described. Nonetheless, PSA is one of the most widely used tumor markers and strongly correlates with the risk of harboring PCa. However, while PSA has limitations for PCa detection with its low specificity there are several potential biomarkers presented in this review with utility for PCa currently being studied. There is an urgent need for new biomarkers especially to detect clinically significant and aggressive PCa. From all PSA-based markers, the FDA-approved prostate health index (phi) shows improved specificity over percent free and total PSA. Another kallikrein panel, 4K, which includes KLK2 has recently shown promise in clinical research studies but has not yet undergone formal validation studies. In urine, prostate cancer gene 3 (PCA3) has also been validated and approved by the FDA for its utility to detect PCa. The potential correlation of PCA3 with cancer aggressiveness requires more clinical studies. The detection of the fusion of androgen-regulated genes with genes of the regulatory transcription factors in tissue of (~)50% of all PCa-patients is a milestone in PCa research. A combination of the urinary assays for TMPRSS2:ERG gene fusion and PCA3 shows an improved accuracy for PCa detection. Overall, the field of PCa biomarker discovery is very exciting and prospective.

More than 1,000,000 men undergo prostate biopsy each year in the United States, most for "elevated" serum prostate-specific antigen (PSA). Given the lack of specificity and unclear mortality benefit of PSA testing, methods to individualize management of elevated PSA are needed. Greater than 50% of PSA-screened prostate cancers harbor fusions between the transmembrane protease, serine 2 (TMPRSS2) and v-ets erythroblastosis virus E26 oncogene homolog (avian) (ERG) genes. Here, we report a clinical-grade, transcription-mediated amplification assay to risk stratify and detect prostate cancer noninvasively in urine. The TMPRSS2:ERG fusion transcript was quantitatively measured in prospectively collected whole urine from 1312 men at multiple centers. Urine TMPRSS2:ERG was associated with indicators of clinically significant cancer at biopsy and prostatectomy, including tumor size, high Gleason score at prostatectomy, and upgrading of Gleason grade at prostatectomy. TMPRSS2:ERG, in combination with urine prostate cancer antigen 3 (PCA3), improved the performance of the multivariate Prostate Cancer Prevention Trial risk calculator in predicting cancer on biopsy. In the biopsy cohorts, men in the highest and lowest of three TMPRSS2:ERG+PCA3 score groups had markedly different rates of cancer, clinically significant cancer by Epstein criteria, and high-grade cancer on biopsy. Our results demonstrate that urine TMPRSS2:ERG, in combination with urine PCA3, enhances the utility of serum PSA for predicting prostate cancer risk and clinically relevant cancer on biopsy.

Objectives: To examine the ability of the urinary prostate cancer gene 3 (PCA3) assay to predict biopsy-detected cancers in men receiving dutasteride in the Reduction by Dutasteride of Prostate Cancer Events (REDUCE) study cohort., Methods: Urine and serum samples from 930 men in the active arm were acquired at years 2 and 4 of the biopsy visits. In addition to univariate logistic regression and receiver operating characteristic analysis, multivariate analysis for association with biopsy outcome was performed for PCA3 score in the presence of serum prostate-specific antigen (PSA), age, prostate volume, and family history of prostate cancer., Results: At year 2, the univariate PCA3 score area under the receiver operating characteristic curve (AUC) was 0.668 versus 0.603 for PSA. At year 4, the PCA3 assay significantly predicted the biopsy outcome (AUC 0.628, 95% confidence interval 0.556-0.700), and the PSA level was not predictive (AUC 0.556, 95% confidence interval 0.469-0.642). The year 2 multivariate model yielded an AUC of 0.712. Removing the PCA3 score decreased the AUC to 0.660 (P = .0166 vs the full model). The median PCA3 scores in the dutasteride arm were not different from those in the 1072 men in the placebo arm (16.2 and 17.2 at year 2, P = .1755; and 18.8 and 18.1 at year 4, P = .2340, respectively). However, the PSA values were reduced >50% in the dutasteride arm at both visits (both P < .0001 vs placebo). At a PCA3 score cutoff of 35, the sensitivity and specificity were equivalent between the 2 arms., Conclusions: In the present study, the PCA3 assay outperformed PSA for cancer detection in men undergoing dutasteride treatment and improved the diagnostic accuracy when combined with the PSA level and other clinical variables. In addition, no adjustment in PCA3 score was needed to yield equivalent clinical performance between the dutasteride and placebo arms. These findings are particularly important in light of the potential role of dutasteride for prostate cancer chemoprevention., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Prostate cancer is the second leading cause of cancer deaths in men in the United States. Use of the serum prostate specific antigen (PSA) test to screen men for prostate cancer since the late 1980s has improved the early detection of prostate cancer, however low specificity of the test translates to numerous false positive results and many unnecessary biopsies. New biomarkers to aid in prostate cancer diagnosis are emerging and prostate cancer gene 3 (PCA3) is one such marker. PCA3 is a noncoding RNA that is highly over-expressed in prostate cancer tissue compared to benign tissue. A non-invasive test for PCA3 was developed using whole urine collected after a digital rectal exam (DRE). Numerous clinical studies have demonstrated the utility of PCA3 for the diagnosis of prostate cancer and some studies suggest that PCA3 may also have prognostic value. The use of PCA3 in combination with serum PSA and other clinical information enhances the diagnostic accuracy of prostate cancer detection and will enable physicians to make more informed decisions with patients at risk for prostate cancer., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

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., (Copyright © 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: Prevalent gene fusions in prostate cancer involve androgen-regulated promoters (primarily TMPRSS2) and ETS transcription factors (predominantly ETS-regulated gene (ERG)], which result in tumor selective overexpression of ERG in two thirds of patients. Because diverse genomic fusion events lead to ERG overexpression in prostate cancer, we reasoned that it may be more practical to capture such alterations using an assay targeting ERG sequences retained in such gene fusions. This study evaluates the potential of an assay quantitating ERG mRNA in post-digital rectal exam (DRE) urine for improving prostate cancer detection., Experimental Design: Patients scheduled to undergo transrectal ultrasound-guided needle biopsy of the prostate were prospectively enrolled. On the day of biopsy, patients provided a urine sample immediately following a DRE. Urine ERG mRNA was measured and normalized to urine prostate-specific antigen (PSA) mRNA using the DTS 400 system. Demographic traits, clinical characteristics and biopsy results were analyzed for association with urine ERG score., Results: The study was conducted on 237 patients. Prostate cancer was shown on biopsy in 40.9% of study subjects. A higher urine ERG score associated significantly with malignancy on biopsy (P = 0.0145), but not with clinical stage or Gleason score. Urine ERG score performed best in Caucasians and in men with a PSA of

The specificity of PSA has been enhanced by using molecular forms of PSA and free PSA (fPSA) such as percent free PSA (%fPSA), proPSA, intact PSA or BPHA and / or new serum markers. Most of these promising new serum markers like EPCA2 or ANXA3 still lack confirmation of the outstanding initial results or show only marginally enhanced specificity at high sensitivity levels. PCA3, TMPRSS2-ERG, and other analytes in urine collected after digital rectal examination with application of mild digital pressure have the potential to preferentially detect aggressive PCa and to decrease the number of unnecessary repeat biopsies. The combination of these new urinary markers with new and established serum markers seems to be most promising to further increase specificity of tPSA. Multivariate models, e. g., artificial neural networks (ANN) or logistic regression (LR) based nomograms have recently been performed by incorporating these new markers in several studies. There is generally an advantage to include the new markers and clinical data as additional parameters to PSA and %fPSA within ANN and LR models. Results of these studies and also unexpected pitfalls are discussed in this review.

Specificity of PSA has been enhanced by using molecular forms of PSA and free PSA (fPSA) such as percent free PSA (% fPSA), proPSA, intact PSA or BPHA and/or new serum markers. Most of these promising new serum markers like EPCA2 or ANXA3 still lack confirmation of outstanding initial results or show only marginal enhanced specificity at high sensitivity levels. PCA3, TMPRSS2-ERG, and other analytes in urine collected after digital rectal examination with application of mild digital pressure have potential to preferentially detect aggressive PCa and to decrease the rate of unnecessary repeat biopsies. The combination of these new urinary markers with new and established serum markers seems to be most promising to further increase specificity of tPSA. Multivariate models e.g. artificial neural networks (ANN) or logistic regression (LR)-based nomograms have been recently developed by incorporating these new markers in several studies. There is generally an advantage to including new markers and clinical data as additional parameters to PSA and % fPSA within ANN and LR models. The results and unexpected pitfalls of these studies are shown.

Background: Updated National Academy of Clinical Biochemistry (NACB) Laboratory Medicine Practice Guidelines for the use of tumor markers in the clinic have been developed., Methods: Published reports relevant to use of tumor markers for 5 cancer sites--testicular, prostate, colorectal, breast, and ovarian--were critically reviewed., Results: For testicular cancer, alpha-fetoprotein, human chorionic gonadotropin, and lactate dehydrogenase are recommended for diagnosis/case finding, staging, prognosis determination, recurrence detection, and therapy monitoring. alpha-Fetoprotein is also recommended for differential diagnosis of nonseminomatous and seminomatous germ cell tumors. Prostate-specific antigen (PSA) is not recommended for prostate cancer screening, but may be used for detecting disease recurrence and monitoring therapy. Free PSA measurement data are useful for distinguishing malignant from benign prostatic disease when total PSA is <10 microg/L. In colorectal cancer, carcinoembryonic antigen is recommended (with some caveats) for prognosis determination, postoperative surveillance, and therapy monitoring in advanced disease. Fecal occult blood testing may be used for screening asymptomatic adults 50 years or older. For breast cancer, estrogen and progesterone receptors are mandatory for predicting response to hormone therapy, human epidermal growth factor receptor-2 measurement is mandatory for predicting response to trastuzumab, and urokinase plasminogen activator/plasminogen activator inhibitor 1 may be used for determining prognosis in lymph node-negative patients. CA15-3/BR27-29 or carcinoembryonic antigen may be used for therapy monitoring in advanced disease. CA125 is recommended (with transvaginal ultrasound) for early detection of ovarian cancer in women at high risk for this disease. CA125 is also recommended for differential diagnosis of suspicious pelvic masses in postmenopausal women, as well as for detection of recurrence, monitoring of therapy, and determination of prognosis in women with ovarian cancer., Conclusions: Implementation of these recommendations should encourage optimal use of tumor markers.

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.