Prospective Multicentre Evaluation of PCA3 and TMPRSS2-ERG Gene Fusions as Diagnostic and Prognostic Urinary Biomarkers for Prostate Cancer

Background

Prostate cancer antigen 3 (PCA3) and v-ets erythroblastosis virus E26 oncogene homolog (TMPRSS2-ERG) gene fusions are promising prostate cancer (PCa) specific biomarkers that can be measured in urine.

Objective

To evaluate the diagnostic and prognostic value of Progensa PCA3 and TMPRSS2-ERG gene fusions (as individual biomarkers and as a panel) for PCa in a prospective multicentre setting.

Design, setting, and participants

At six centres, post–digital rectal examination first-catch urine specimens prior to prostate biopsies were prospectively collected from 497 men. We assessed the predictive value of Progensa PCA3 and TMPRSS2-ERG (quantitative nucleic acid amplification assay to detect TMPRSS2-ERG messenger RNA [mRNA]) for PCa, Gleason score, clinical tumour stage, and PCa significance (individually and as a marker panel). This was compared with serum prostate-specific antigen and the European Randomised Study of Screening for Prostate Cancer (ERSPC) risk calculator. In a subgroup (n = 61) we evaluated biomarker association with prostatectomy outcome.

Outcome measurements and statistical analysis

Univariate and multivariate logistic regression analysis and receiver operating curves were used.

Results and limitations

Urine samples of 443 men contained sufficient mRNA for marker analysis. PCa was diagnosed in 196 of 443 men. Both PCA3 and TMPRSS2-ERG had significant additional predictive value to the ERSPC risk calculator parameters in multivariate analysis (p < 0.001 and resp. p = 0.002). The area under the curve (AUC) increased from 0.799 (ERSPC risk calculator), to 0.833 (ERSPC risk calculator plus PCA3), to 0.842 (ERSPC risk calculator plus PCA3 plus TMPRSS2-ERG) to predict PCa. Sensitivity of PCA3 increased from 68% to 76% when combined with TMPRSS2-ERG. TMPRSS2-ERG added significant predictive value to the ERSPC risk calculator to predict biopsy Gleason score (p < 0.001) and clinical tumour stage (p = 0.023), whereas PCA3 did not.

Conclusions

TMPRSS2-ERG had independent additional predictive value to PCA3 and the ERSPC risk calculator parameters for predicting PCa. TMPRSS2-ERG had prognostic value, whereas PCA3 did not. Implementing the novel urinary biomarker panel PCA3 and TMPRSS2-ERG into clinical practice would lead to a considerable reduction of the number of prostate biopsies.     

Potential Impact of Adding Genetic Markers to Clinical Parameters in Predicting Prostate Biopsy Outcomes in Men Following an Initial Negative Biopsy: Findings from the REDUCE Trial

Background

Several germline single nucleotide polymorphisms (SNPs) have been consistently associated with prostate cancer (PCa) risk.

Objective

To determine whether there is an improvement in PCa risk prediction by adding these SNPs to existing predictors of PCa.

Design, setting, and participants

Subjects included men in the placebo arm of the randomized Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial in whom germline DNA was available. All men had an initial negative prostate biopsy and underwent study-mandated biopsies at 2 yr and 4 yr. Predictive performance of baseline clinical parameters and/or a genetic score based on 33 established PCa risk-associated SNPs was evaluated.

Outcome measurements and statistical analysis

Area under the receiver operating characteristic curves (AUC) were used to compare different models with different predictors. Net reclassification improvement (NRI) and decision curve analysis (DCA) were used to assess changes in risk prediction by adding genetic markers.

Results and limitations

Among 1654 men, genetic score was a significant predictor of positive biopsy, even after adjusting for known clinical variables and family history (p = 3.41 × 10⁻⁸). The AUC for the genetic score exceeded that of any other PCa predictor at 0.59. Adding the genetic score to the best clinical model improved the AUC from 0.62 to 0.66 (p < 0.001), reclassified PCa risk in 33% of men (NRI: 0.10; p = 0.002), resulted in higher net benefit from DCA, and decreased the number of biopsies needed to detect the same number of PCa instances. The benefit of adding the genetic score was greatest among men at intermediate risk (25th percentile to 75th percentile). Similar results were found for high-grade (Gleason score ≥7) PCa. A major limitation of this study was its focus on white patients only.

Conclusions

Adding genetic markers to current clinical parameters may improve PCa risk prediction. The improvement is modest but may be helpful for better determining the need for repeat prostate biopsy. The clinical impact of these results requires further study.     

Alcohol Intake Increases High-grade Prostate Cancer Risk Among Men Taking Dutasteride in the REDUCE Trial

Background

Although most studies found no association between alcohol intake and prostate cancer (PCa) risk, an analysis of the Prostate Cancer Prevention Trial found that high alcohol intake significantly increased PCa risk among men randomized to the 5α-reductase inhibitor (5-ARI) finasteride.

Objective

Determine whether alcohol affects PCa risk among men taking the 5-ARI dutasteride.

Design, settings, and participants

Reduction by Dutasteride of Prostate Cancer Events was a 4-yr, multicenter, randomized, double-blind, placebo-controlled trial to compare PCa after dutasteride administration (0.5 mg/d) with placebo. Participants had a baseline prostate-specific antigen between 2.5 and 10.0 ng/ml and a recent negative prostate biopsy. Alcohol intake was determined by baseline questionnaire, and participants underwent a prostate biopsy to determine PCa status at 2 yr and 4 yr of follow-up.

Outcome measurements and statistical analysis

Multivariable logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between alcohol intake and low-grade (Gleason <7) and high-grade (Gleason >7) PCa.

Results and limitations

Of 6374 participants in our analysis, approximately 25% reported no alcohol consumption, 49% were moderate drinkers (one to seven drinks per week), and 26% were heavy drinkers (more than seven drinks per week). Alcohol intake was not associated with low- or high-grade PCa in the placebo arm and was not associated with low-grade PCa among men taking dutasteride. In contrast, men randomized to dutasteride and reporting more than seven drinks per week were 86% more likely to be diagnosed with high-grade PCa (p = 0.01). Among alcohol abstainers, dutasteride was associated with significantly reduced risk of high-grade PCa (OR: 0.59; 95% CI, 0.38–0.90), but dutasteride was no longer associated with reduced high-grade PCa among men reporting high alcohol intake (OR: 0.99; 95% CI, 0.67–1.45).

Conclusions

Alcohol consumption negated a protective association between dutasteride and high-grade PCa.

Patient summary

We confirmed a prior study that alcohol affects PCa prevention in patients taking 5-ARIs. Patients taking 5-ARIs may wish to eliminate alcohol intake if they are concerned about PCa.     

Serum Isoform [−2]proPSA Derivatives Significantly Improve Prediction of Prostate Cancer at Initial Biopsy in a Total PSA Range of 2–10 ng/ml: A Multicentric European Study

Background

Strategies to reduce prostate-specific antigen (PSA)–driven prostate cancer (PCa) overdiagnosis and overtreatment seem to be necessary.

Objective

To test the accuracy of serum isoform [−2]proPSA (p2PSA) and its derivatives, percentage of p2PSA to free PSA (fPSA; %p2PSA) and the Prostate Health Index (PHI)—called index tests—in discriminating between patients with and without PCa.

Design, setting, and participants

This was an observational, prospective cohort study of patients from five European urologic centers with a total PSA (tPSA) range of 2–10 ng/ml who were subjected to initial prostate biopsy for suspected PCa.

Outcome measurements and statistical analysis

The primary end point was to evaluate the specificity, sensitivity, and diagnostic accuracy of index tests in determining the presence of PCa at prostate biopsy in comparison to tPSA, fPSA, and percentage of fPSA to tPSA (%fPSA) (standard tests) and the number of prostate biopsies that could be spared using these tests. Multivariable logistic regression models were complemented by predictive accuracy analysis and decision curve analysis.

Results and limitations

Of >646 patients, PCa was diagnosed in 264 (40.1%). Median tPSA (5.7 vs 5.8 ng/ml; p = 0.942) and p2PSA (15.0 vs 14.7 pg/ml) did not differ between groups; conversely, median fPSA (0.7 vs 1 ng/ml; p < 0.001), %fPSA (0.14 vs 0.17; p < 0.001), %p2PSA (2.1 vs 1.6; p < 0.001), and PHI (48.2 vs 38; p < 0.001) did differ significantly between men with and without PCa. In multivariable logistic regression models, p2PSA, %p2PSA, and PHI significantly increased the accuracy of the base multivariable model by 6.4%, 5.6%, and 6.4%, respectively (all p < 0.001). At a PHI cut-off of 27.6, a total of 100 (15.5%) biopsies could have been avoided. The main limitation is that cases were selected on the basis of their initial tPSA values.

Conclusions

In patients with a tPSA range of 2–10 ng/ml, %p2PSA and PHI are the strongest predictors of PCa at initial biopsy and are significantly more accurate than tPSA and %fPSA.

Trial registration

The study is registered at http://www.controlled-trials.com, ref. ISRCTN04707454.     

Performance of the Prostate Cancer Antigen 3 (PCA3) Gene and Prostate-Specific Antigen in Prescreened Men: Exploring the Value of PCA3 for a First-line Diagnostic Test

Background

The performance characteristics of serum prostate-specific antigen (PSA) as a diagnostic test for prostate cancer (PCa) are poor. The performance of the PCa antigen 3 (PCA3) gene as a primary diagnostic is unknown.

Objective

Assess the value of PCA3 as a first-line diagnostic test.

Design, setting and participants

Participants included men aged 63–75 who were invited for rescreening in the period from September 2007 to February 2009 within the European Randomised Study of Screening for Prostate Cancer, Rotterdam section.

Interventions

Lateral sextant biopsies were performed if the serum PSA value was ≥3.0 ng/ml and/or the PCA3 score was ≥10.

Measurements

Measurements included distribution and correlation of PSA value and PCA3 score and their relation to the number of cases and the characteristics of PCa detected. Additional value of PCA3 was included in men with previous negative biopsy and/or PSA <3.0 ng/ml.

Results and limitations

In 721 men, all biopsied, 122 PCa cases (16.9%) were detected. Correlation between PSA and PCA3 is poor (Spearman rank correlation: ρ = 0.14; p < 0.0001). A PSA ≥3.0 ng/ml misses 64.7% of the total PCa that can be detected with the sextant biopsy technique and 57.9% of serious PCa (T2a or higher and/or Gleason grade ≥4, n = 19), and 68.2% of biopsies could have been avoided; the respective data for PCA3 ≥35 are 32%, 26.3%, and 51.7%. Performance of PCA3 in men with low PSA (area under the curve [AUC]: 0.63) and/or previous negative biopsy (AUC: 0.68) is unclear but has limited reliability due to small numbers.

Conclusions

PCA3 as a first-line screening test shows improvement of the performance characteristics and identification of serious disease compared with PSA in this prescreened population.     

Initial Prostate Biopsy: Development and Internal Validation of a Biopsy-specific Nomogram Based on the Prostate Cancer Antigen 3 Assay

Background

Urinary prostate cancer antigen 3 (PCA3) assay in combination with established clinical risk factors improves the identification of men at risk of harboring prostate cancer (PCa) at initial biopsy (IBX).

Objective

To develop and validate internally the first IBX-specific PCA3-based nomogram that allows an individual assessment of a man's risk of harboring any PCa and high-grade PCa (HGPCa).

Design, setting, and participants

Clinical and biopsy data including urinary PCA3 score of 692 referred IBX men at risk of PCa were collected within two prospective multi-institutional studies.

Intervention

IBX (≥10 biopsy cores) with standard risk factor assessment including prebiopsy urinary PCA3 measurement.

Outcome measurements and statistical analysis

PCA3 assay cut-off thresholds were investigated. Regression coefficients of logistic risk factor analyses were used to construct specific sets of PCA3-based nomograms to predict any PCa and HGPCa at IBX. Accuracy estimates for the presence of any PCa and HGPCa were quantified using area under the curve of the receiver operator characteristic analysis and compared with a clinical model. Bootstrap resamples were used for internal validation. Decision curve analyses quantified the clinical net benefit related to the novel PCA3-based IBX nomogram versus the clinical model.

Results and limitations

Any PCa and HGPCa were diagnosed in 46% (n = 318) and 20% (n = 137), respectively. Age, prostate-specific antigen, digital rectal examination, prostate volume, and PCA3 were independent predictors of PCa at IBX (all p < 0.001). The PCA3-based IBX nomograms significantly outperformed the clinical models without PCA3 (all p < 0.001). Accuracy was increased by 4.5–7.1% related to PCA3 inclusion. When applying nomogram-derived PCa probability thresholds ≤30%, only a few patients with HGPCa (≤2%) will be missed while avoiding up to 55% of unnecessary biopsies. External validation of the PCA3-based IBX-specific nomogram is warranted.

Conclusions

The internally validated PCA3-based IBX-specific nomogram outperforms a clinical prediction model without PCA3 for the prediction of any PCa, leading to the avoidance of unnecessary biopsies while missing only a few cases of HGPCa. Our findings support the concepts of a combination of novel markers with established clinical risk factors and the superiority of decision tools that are specific to a clinical scenario.     

Multicenter European External Validation of a Prostate Health Index–based Nomogram for Predicting Prostate Cancer at Extended Biopsy

Background

External validation of a prediction tool is mandatory to assess the tool's accuracy and generalizability within different patient cohorts.

Objective

To externally validate a previously developed Prostate Health Index (PHI)–based nomogram for predicting the presence of prostate cancer (PCa) at biopsy.

Design, setting, and participants

The study population consisted of 883 patients who were scheduled for a prostate biopsy at one of five European tertiary care centers. Total prostate-specific antigen (tPSA), free prostate-specific antigen (fPSA), and [−2]pro–prostate-specific antigen (p2PSA) levels were determined. The fPSA-to-tPSA ratio (%fPSA), p2PSA, and PHI ([p2PSA / fPSA] × √tPSA) were calculated.

Intervention

Extended initial and repeat prostate biopsy.

Outcome measurements and statistical analysis

Logistic regression models were fitted to test the predictors of PCa and to determine their predictive accuracy. A calibration plot was used to evaluate the extent of overestimation or underestimation between nomogram predictions and observed PCa rate. Decision curve analysis (DCA) provided an estimate of the net benefit obtained by using the PHI-based nomogram.

Results and limitations

Of 833 patients, 365 (41.3%) were diagnosed with PCa at extended prostate biopsy. In accuracy analyses, PHI was the most informative predictor of PCa (0.68), outperforming tPSA (0.51) and %fPSA (0.64). The predictive accuracy of the previously developed nomogram was 75.2% (95% confidence interval, 71.4–78.1). Calibration of the nomogram was good in patients at a low to intermediate predicted probability of PCa, while calibration was suboptimal, with a tendency to overestimate the presence of PCa, in high-risk patients. Finally, DCA demonstrated that the use of the PHI-based nomogram resulted in the highest net benefit. The main limitation of the study is the fact that only Caucasian patients were included.

Conclusions

At external validation, the previously developed PHI-based nomogram confirmed its ability to determine the presence of PCa at biopsy. These findings provide further evidence supporting the potential role of the nomogram in the biopsy decision pathway for European men with suspected PCa.

Patient summary

In the current study, we externally validated a Prostate Health Index–based nomogram to predict the presence of prostate cancer (PCa) at biopsy. This tool may help clinicians determine the need for a prostate biopsy in European patients with suspected PCa.     

Is an Initial Saturation Prostate Biopsy Scheme Better than an Extended Scheme for Detection of Prostate Cancer? A Systematic Review and Meta-analysis

Context

The optimal initial prostate biopsy core number is still an issue with many unanswered questions and significant controversy.

Objective

To compare diagnostic values of initial saturation prostate biopsy scheme and extended scheme with respect to prostate-specific antigen (PSA) levels, prostate volume (PV), and PSA density (PSAD).

Evidence acquisition

Electronic databases including Medline, Web of Knowledge, and the Cochrane Library were searched through November 1, 2012. Experts were consulted, and references from relevant articles were scanned. The meta-analysis was conducted with RevMan 5.1, according to the PRISMA guidelines. Mantel-Haenszel estimates were calculated and pooled under a fixed or random effect model, with data expressed as risk difference (RD) and 95% confidence interval (CI).

Evidence synthesis

We analyzed eight trials with a total of 11 997 participants who underwent transrectal ultrasound guided prostate biopsies for the first time and met inclusion criteria. Studies consisted of one paired design study, two randomized clinical trials, and five nonrandomized studies. Saturation biopsy scheme showed a significant advantage in prostate cancer (PCa) detection over an extended scheme (RD: 0.04; 95% CI, 0.01–0.08; p = 0.02). In addition, subgroup analyses found a saturation protocol to be superior to an extended protocol in the detection of PCa in men with PSA <10 ng/ml (RD: 0.04; 95% CI, 0.01–0.07; p = 0.002), PV >40 ml (RD: 0.05; 95%CI, 0.01–0.09; p = 0.02), or PSAD <0.25 ng/ml per gram (RD: 0.04; 95% CI, 0.00–0.09; p = 0.04).

Conclusions

The existing evidence indicates that an initial saturation biopsy scheme is more efficient than an extended scheme for PCa detection, especially for those men with lower PSA levels, higher PV, or lower PSAD, without increasing complications and the amount of insignificant cancer.     

The Effect of Benign Lower Urinary Tract Symptoms on Subsequent Prostate Cancer Testing and Diagnosis

Background

Lower urinary tract symptoms (LUTS) are common and have been associated with the subsequent diagnosis of prostate cancer (PCa) in population cohorts.

Objective

To determine whether the association between LUTS and PCa is due to the intensity of PCa testing after LUTS diagnosis.

Design, setting, and participants

We prospectively followed a representative, population-based cohort of 1922 men, aged 40–79 yr, from 1990 until 2010 with interviews, questionnaires, and abstracting of medical records for prostate outcomes. Men were excluded if they had a previous prostate biopsy or PCa diagnosis. Self-reported LUTS was defined as an American Urological Association symptom index score >7 (n = 621). Men treated for LUTS (n = 168) were identified from review of medical records and/or self report. Median follow-up was 11.8 yr (interquartile range: 10.7–12.3).

Outcome measurements and statistical analysis

Associations between self-reported LUTS, or treatment for LUTS, and risk of subsequent prostate biopsy and PCa were estimated using Cox proportional hazard models.

Results and limitations

Fifty-five percent of eligible men enrolled in the study. Men treated for LUTS were more likely to undergo a prostate biopsy (hazard ratio [HR]: 2.4; 95% confidence interval [CI], 1.7–3.3). Men younger than 65 yr who were treated for LUTS were more likely to be diagnosed with PCa (HR: 2.3, 95% CI, 1.5–3.5), while men aged >65 yr were not (HR: 0.89, 95% CI, 0.35–1.9). Men with self-reported LUTS were not more likely to be biopsied or diagnosed with PCa. Neither definition of LUTS was associated with subsequent intermediate- to high-risk cancer. The study is limited by lack of histologic or prostate-specific antigen level data for the cohort.

Conclusions

These results indicate that a possible cause of the association between LUTS and PCa is increased diagnostic intensity among men whose LUTS come to the attention of physicians. Increased symptoms themselves were not associated with intensity of testing or diagnosis.     

Thromboembolic Events Following Surgery for Prostate Cancer

Background

Prostate cancer (PCa) and surgery are both associated with increased risk of thromboembolic diseases (TED).

Objective

We assessed risk of TED among men undergoing different types of urologic surgery.

Design, setting, and participants

Using the Prostate Cancer Database Sweden (PCBaSe) Sweden, we identified all men (n = 45 065) undergoing pelvic lymph node dissection (PLND), radical prostatectomy (RP) with or without PLND, orchiectomy due to PCa, or a transurethral resection of the prostate (TURP). We identified a comparison cohort from the population.

Outcome measurements and statistical analysis

Main outcomes were deep venous thrombosis (DVT) and pulmonary embolism (PE) as primary diagnoses in the National Patient Register or Cause of Death Register (2002–2010). We calculated hazard ratios (HR) and 95% confidence intervals (CI) using multivariable Cox proportional hazards models.

Results and limitations

All surgical procedures were associated with increased risk of TED; laparoscopic and open RP with a PLND were the most strongly associated with TED (HR for PE: 8.1 [95% CI, 2.9–23.0] and 7.8 [95% CI, 4.9–13], respectively). For surgery including a PLND, the risk increased during the second half of the first postoperative month. The HR for PE after TURP in men with PCa was 3.0 (95% CI, 1.8–5.1). Patients with a history of TED had a strongly increased risk of TED (HR for DVT: 4.5; 95% CI, 2.6–8.0). A limitation is lack of information on TED prophylaxis, but its use was standardized during the study period for RP and PLND. Other limitations are lack of information on extent of PLND and lifestyle factors.

Conclusions

Surgeries for PCa, including TURP, are associated with hospitalization for TED. Patients with a history of TED and patients undergoing a PLND were at highest risk. The largest risk was observed from days 14 to 28 postoperatively. Thus, our results suggest that prophylactic measures may be beneficial during the first 4 wk in these patients.     

Biochemical Recurrence Following Robot-Assisted Radical Prostatectomy: Analysis of 1384 Patients with a Median 5-year Follow-up

Background

There is a paucity of data on long-term oncologic outcomes for patients undergoing robot-assisted radical prostatectomy (RARP) for prostate cancer (PCa).

Objective

To evaluate oncologic outcomes in patients undergoing RARP at a high-volume tertiary center, with a focus on 5-yr biochemical recurrence–free survival (BCRFS).

Design, setting, and participants

The study cohort consisted of 1384 consecutive patients with localized PCa who underwent RARP between September 2001 and May 2005 and had a median follow-up of 60.2 mo. No patient had secondary therapy until documented biochemical recurrence (BCR). BCR was defined as a serum prostate-specific antigen ≥0.2 ng/ml with a confirmatory value. BCRFS was estimated using the Kaplan-Meier method. Event–time distributions for the time to failure were compared using the log-rank test. Univariable and multivariable Cox proportional hazards regression models were used to determine variables predictive of BCR.

Intervention

All patients underwent RARP.

Measurements

BCRFS rates were measured.

Results and limitations

This cohort of patients had moderately aggressive PCa: 49.0% were D’Amico intermediate or high risk on biopsy; however, 60.9% had Gleason 7–10 disease, and 25.5% had ≥T3 disease on final pathology. There were 189 incidences of BCR (31 per 1,000 person years of follow-up) at a median follow-up of 60.2 mo (interquartile range [IQR]: 37.2–69.7). The actuarial BCRFS was 95.1%, 90.6%, 86.6%, and 81.0% at 1, 3, 5, and 7 yr, respectively. In the patients who recurred, median time to BCR was 20.4 mo; 65% of BCR incidences occurred within 3 yr and 86.2% within 5 yr. On multivariable analysis, the strongest predictors of BCR were pathologic Gleason grade 8–10 (hazard ratio [HR]: 5.37; 95% confidence interval [CI], 2.99–9.65; p < 0.0001) and pathologic stage T3b/T4 (HR: 2.71; 95% CI, 1.67–4.40; p < 0.0001).

Conclusions

In a contemporary cohort of patients with localized PCa, RARP confers effective 5-yr biochemical control.     

Prognostic Parameters,Complications, and Oncologic and Functional Outcome of Salvage Radical Prostatectomy for Locally Recurrent Prostate Cancer after 21st-Century Radiotherapy

Background

Salvage radical prostatectomy (SRP) for radiorecurrent prostate cancer (PCa) is a second local treatment with curative intent in patients with true organ-confined recurrent PCa.

Objective

We evaluated preoperative prognostic risk factors to predict organ-confined, locally recurrent PCa after primary radiotherapy (RT).

Design, setting, and participants

Fifty-five men with biopsy-proven, locally recurrent PCa underwent SRP and extended pelvic lymph node dissection (ePLND) after external-beam radiotherapy (EBRT) or low- or high-dose brachytherapy.

Measurements

Prostate-specific antigen (PSA), clinical stage, biopsy Gleason score prior to RT and SRP, PSA nadir, time to recurrence, PSA doubling time (PSA DT), PSA prior to surgery, and pathohistology of the SRP specimen were analysed to predict organ-confined recurrent disease. Uni- and multivariate statistical analysis was performed.

Results and limitations

Forty (72.7%) and 15 (27.3%) patients demonstrated organ-confined and locally advanced PCa, respectively. Eleven patients (20%) and seven patients (12.7%) had lymph node metastases and positive surgical margins (PSM), respectively. On multivariate analysis, biopsy Gleason score prior to SRP (p = 0.02), <50% positive biopsy cores (p = 0.001), PSA DT >12 mo (p = 0.001), and low-dose brachytherapy (p = 0.001) were significant predictors of organ-confined PCa with negative surgical margins (NSM). Limitations of the study are its retrospective nature and the relatively low number of patients.

Conclusions

SRP is a surgically challenging but effective secondary local treatment of radiorecurrent PCa with curative intent. The identified predictive parameters will help to select patients most suitable for SRP with long-term cure and good functional outcome.     

Neoadjuvant Hormonal Therapy Use and the Risk of Death in Men with Prostate Cancer Treated with Brachytherapy Who Have No or at Least a Single Risk Factor for Coronary Artery Disease

Background

Neoadjuvant hormone therapy (NHT) use is associated with an increased risk of all-cause mortality (ACM) in men with a history of coronary artery disease (CAD)–induced congestive heart failure (CHF) or myocardial infarction (MI). However, its effect in men with no or at least a single risk factor for CAD stratified by prostate cancer (PCa) aggressiveness is unknown.

Objective

To assess whether NHT use affects the risk of ACM in men with low-, intermediate-, and high-risk PCa treated with brachytherapy who have no or at least a single risk factor for CAD.

Design, setting, and participants

This retrospective study cohort consisted of 5411 men with low-risk PCa (prostate-specific antigen [PSA] <10 ng/ml, Gleason score 6, and clinical stage T1–T2a); 4365 men with intermediate-risk PCa (PSA 10–20 ng/ml or Gleason score <8 or clinical stage <T3); and 1360 men with localized or locally advanced, high-risk PCa consecutively treated in a community-based, multi-institutional setting between 1991 and 2006. CAD risk factors included at least a history of diabetes mellitus, hypercholesterolemia, or hypertension. The median follow-up for men with low-, intermediate-, and high-risk PCa were 4.1, 4.4, and 4.6 yr, respectively.

Interventions

Men were treated with or without a median duration of 4 mo of NHT followed by brachytherapy with or without supplemental external-beam radiation therapy (EBRT).

Outcome measurements and statistical analysis

Cox regression multivariable analyses were performed to assess whether NHT use affected the risk of ACM in men with low-, intermediate-, and high-risk PCa, adjusting for age; year of brachytherapy; supplemental EBRT use; the presence of CAD risk factors; treatment propensity score; and known PCa prognostic factors, including pretreatment PSA level, biopsy Gleason score, and clinical stage.

Results and limitations

NHT use was associated with a significantly increased risk of ACM in men with low-risk PCa (adjusted hazard ratio [HR]: 1.27; 95% confidence interval [CI], 1.07–1.51; p < 0.01) but not in men with intermediate-risk (adjusted HR: 1.13; 95% CI, 0.96–1.35; p = 0.15) or high-risk PCa (adjusted HR: 0.86; 95% CI, 0.66–1.13; p = 0.28). Using an interaction model for the low-risk group, NHT use was associated with a significantly increased risk of ACM in the subgroup of men with at least a single CAD risk factor (adjusted HR: 1.36; 95% CI, 1.07–1.74; p = 0.01) but not for men with no CAD risk factors (adjusted HR: 1.19; 95% CI, 0.95–1.51; p = 0.13).

Conclusions

For men with no or at least a single risk factor for CAD, NHT use is associated with an increased risk of ACM in the setting of low-risk but not intermediate- or high-risk PCa. This effect is driven by the subgroup of men with at least a single risk factor for CAD. These results warrant prospective validation given the widespread use of NHT for prostate downsizing prior to brachytherapy.     

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.     

A Genetic Score Can Identify Men at High Risk for Prostate Cancer Among Men With Prostate-Specific Antigen of 1–3 ng/ml

Background

The diagnostic performance of a genetic score based on single nucleotide polymorphisms (SNPs) is unknown in the prostate-specific antigen (PSA) range of 1–3 ng/ml. A substantial proportion of men in this PSA span have prostate cancer (PCa), but biomarkers to determine who should undergo a prostate biopsy are lacking.

Objective

To evaluate whether a genetic risk score identifies men in the PSA range of 1–3 ng/ml who are at higher risk for PCa.

Design, setting, and participants

Men aged 50–69 yr with PSA 1–3 ng/ml and without a previous prostate biopsy were selected from the STHLM2 cohort. Of 2696 men, 49 SNPs were genotyped, and a polygenic risk score was calculated. Of these men, 860 were invited according to risk score, and 172 underwent biopsy.

Outcome measurements and statistical analysis

The risk of PCa was assessed using univariate and multivariate logistic regression analysis.

Results and limitations

PCa was diagnosed in 47 of 172 participants (27%), with Gleason sum 6 in 36 of 47 men (77%) and Gleason sum ≥7 in 10 of 47 men (21%); one man had intraductal cancer. The genetic score was a significant predictor of a positive biopsy (p = 0.028), even after adjusting for PSA, ratio of free to total PSA, prostate volume, age, and family history. There was an increase in the odds ratio of 1.60 (95% confidence interval, 1.05–2.45) with increasing genetic risk score. The absolute risk difference of positive biopsy was 19 percentage points, comparing the high and low genetic risk group (37% vs 18%).

Conclusions

A risk score based on SNPs predicts biopsy outcome in previously unbiopsied men with PSA 1–3 ng/ml. Introducing a genetic-based risk stratification tool can increase the proportion of men being classified in line with their true risk of PCa.     

A New Risk Classification System for Therapeutic Decision Making with Intermediate-risk Prostate Cancer Patients Undergoing Dose-escalated External-beam Radiation Therapy

Background

The management of intermediate-risk prostate cancer (PCa) is controversial, in part due to the heterogeneous nature of patients falling within this classification.

Objective

We propose a new risk stratification system for intermediate-risk PCa to aid in prognosis and therapeutic decision making.

Design, setting, and participants

Between 1992 and 2007, 1024 patients with National Comprehensive Cancer Network intermediate-risk PCa and complete biopsy information were treated with definitive external-beam radiation therapy (EBRT) utilizing doses ≥81 Gy. Unfavorable intermediate-risk (UIR) PCa was defined as any intermediate-risk patient with a primary Gleason pattern of 4, percentage of positive biopsy cores (PPBC) ≥50%, or multiple intermediate-risk factors (IRFs; cT2b–c, prostate-specific antigen [PSA] 10–20, or Gleason score 7).

Intervention

All patients received EBRT with ≥81 Gy with or without neoadjuvant and concurrent androgen-deprivation therapy (ADT).

Outcome measurements and statistical analysis

Univariate and multivariate analyses were performed using a Cox proportional hazards model for PSA recurrence-free survival (PSA-RFS) and distant metastasis (DM). PCa-specific mortality (PCSM) was analyzed using a competing-risk method.

Results and limitations

Median follow-up was 71 mo. Primary Gleason pattern 4 (hazard ratio [HR]: 3.26; p < 0.0001), PPBC ≥50% (HR: 2.72; p = 0.0007), and multiple IRFs (HR: 2.20; p = 0.008) all were significant predictors of increased DM in multivariate analyses. Primary Gleason pattern 4 (HR: 5.23; p < 0.0001) and PPBC ≥50% (HR: 4.08; p = 0.002) but not multiple IRFs (HR: 1.74; p = 0.21) independently predicted for increased PCSM. Patients with UIR disease had inferior PSA-RFS (HR: 2.37; p < 0.0001), DM (HR: 4.34; p = 0.0003), and PCSM (HR: 7.39; p = 0.007) compared with those with favorable intermediate-risk disease, despite being more likely to receive neoadjuvant ADT. Short follow-up and retrospective study design are the primary limitations.

Conclusions

Intermediate-risk PCa is a heterogeneous collection of diseases that can be separated into favorable and unfavorable subsets. These groups likely will benefit from divergent therapeutic paradigms.     

The Added Value of Percentage of Free to Total Prostate-specific Antigen,PCA3, and a Kallikrein Panel to the ERSPC Risk Calculator for Prostate Cancer in Prescreened Men

Background

Prostate-specific antigen (PSA) testing has limited accuracy for the early detection of prostate cancer (PCa).

Objective

To assess the value added by percentage of free to total PSA (%fPSA), prostate cancer antigen 3 (PCA3), and a kallikrein panel (4k-panel) to the European Randomised Study of Screening for Prostate Cancer (ERSPC) multivariable prediction models: risk calculator (RC) 4, including transrectal ultrasound, and RC 4 plus digital rectal examination (4+DRE) for prescreened men.

Design, setting, and participants

Participants were invited for rescreening between October 2007 and February 2009 within the Dutch part of the ERSPC study. Biopsies were taken in men with a PSA level ≥3.0 ng/ml or a PCA3 score ≥10. Additional analyses of the 4k-panel were done on serum samples.

Outcome measurements and statistical analysis

Outcome was defined as PCa detectable by sextant biopsy. Receiver operating characteristic curve and decision curve analyses were performed to compare the predictive capabilities of %fPSA, PCA3, 4k-panel, the ERSPC RCs, and their combinations in logistic regression models.

Results and limitations

PCa was detected in 119 of 708 men. The %fPSA did not perform better univariately or added to the RCs compared with the RCs alone. In 202 men with an elevated PSA, the 4k-panel discriminated better than PCA3 when modelled univariately (area under the curve [AUC]: 0.78 vs 0.62; p = 0.01). The multivariable models with PCA3 or the 4k-panel were equivalent (AUC: 0.80 for RC 4+DRE). In the total population, PCA3 discriminated better than the 4k-panel (univariate AUC: 0.63 vs 0.56; p = 0.05). There was no statistically significant difference between the multivariable model with PCA3 (AUC: 0.73) versus the model with the 4k-panel (AUC: 0.71; p = 0.18). The multivariable model with PCA3 performed better than the reference model (0.73 vs 0.70; p = 0.02). Decision curves confirmed these patterns, although numbers were small.

Conclusions

Both PCA3 and, to a lesser extent, a 4k-panel have added value to the DRE-based ERSPC RC in detecting PCa in prescreened men.

Patient summary

We studied the added value of novel biomarkers to previously developed risk prediction models for prostate cancer. We found that inclusion of these biomarkers resulted in an increase in predictive ability.     

Long-Term Follow-up of Patients with Prostate Cancer and Nodal Metastases Treated by Pelvic Lymphadenectomy and Radical Prostatectomy: The Positive Impact of Adjuvant Radiotherapy

Background

Recent large, prospective, randomised studies have demonstrated that adjuvant radiotherapy (RT) is a safe and effective procedure for preventing disease recurrence in locally advanced prostate cancer (PCa) patients. However, no study has ever tested the role of adjuvant RT in node-positive patients after radical prostatectomy (RP).

Objective

We hypothesised that adjuvant RT with early hormone therapy (HT) might improve long-term outcomes of patients with PCa and nodal metastases treated with RP and extended pelvic lymph node dissection (ePLND).

Design, setting, and participants

This retrospective study included 250 consecutive patients with pathologic lymph node invasion. We assessed factors predicting long-term biochemical recurrence (BCR)–free and cancer-specific survival (CSS) in node-positive PCa patients treated with RP, ePLND, and adjuvant treatments between 1988 and 2002 in a tertiary academic centre.

Intervention

All patients received adjuvant treatments according to the treating physician after detailed patient information: 129 patients (51.6%) were treated with a combination of RT and HT, while 121 patients (48.4%) received adjuvant HT alone.

Measurements

BCR-free survival and CSS in patients with node-positive PCa.

Results and limitations

Mean follow-up was 95.9 mo (median: 91.2). BCR-free survival and CSS rates at 5, 8, and 10 yr were 72%, 61%, 53% and 89%, 83%, 80%, respectively. In multivariable Cox regression models, adjuvant RT and the number of positive nodes were independent predictors of BCR-free survival (p = 0.002 and p = 0.003, respectively) as well as of CSS (p = 0.009 and p = 0.01, respectively). Moreover, there was significant gain in predictive accuracy when adjuvant RT was included in multivariable models predicting BCR-free survival and CSS (gain: 3.3% and 3%, respectively; all p < 0.001).

Conclusions

Our data showed excellent long-term outcome for node-positive PCa patients treated with radical surgery plus adjuvant treatments. This study is the first to report a significant protective role for adjuvant RT in BCR-free survival and CSS of node-positive patients.     

External Validation of Urinary PCA3-Based Nomograms to Individually Predict Prostate Biopsy Outcome

Background

Prior to safely adopting risk stratification tools, their performance must be tested in an external patient cohort.

Objective

To assess accuracy and generalizability of previously reported, internally validated, prebiopsy prostate cancer antigen 3 (PCA3) gene-based nomograms when applied to a large, external, European cohort of men at risk of prostate cancer (PCa).

Design, setting, and participants

Biopsy data, including urinary PCA3 score, were available for 621 men at risk of PCa who were participating in a European multi-institutional study.

Intervention

All patients underwent a ≥10-core prostate biopsy. Biopsy indication was based on suspicious digital rectal examination, persistently elevated prostate-specific antigen level (2.5–10 ng/ml) and/or suspicious histology (atypical small acinar proliferation of the prostate, >/= two cores affected by high-grade prostatic intraepithelial neoplasia in first set of biopsies).

Measurements

PCA3 scores were assessed using the Progensa assay (Gen-Probe Inc, San Diego, CA, USA). According to the previously reported nomograms, different PCA3 score codings were used. The probability of a positive biopsy was calculated using previously published logistic regression coefficients. Predicted outcomes were compared to the actual biopsy results. Accuracy was calculated using the area under the curve as a measure of discrimination; calibration was explored graphically.

Results and limitations

Biopsy-confirmed PCa was detected in 255 (41.1%) men. Median PCA3 score of biopsy-negative versus biopsy-positive men was 20 versus 48 in the total cohort, 17 versus 47 at initial biopsy, and 37 versus 53 at repeat biopsy (all p ≤ 0.002). External validation of all four previously reported PCA3-based nomograms demonstrated equally high accuracy (0.73–0.75) and excellent calibration. The main limitations of the study reside in its early detection setting, referral scenario, and participation of only tertiary-care centers.

Conclusions

In accordance with the original publication, previously developed PCA3-based nomograms achieved high accuracy and sufficient calibration. These novel nomograms represent robust tools and are thus generalizable to European men at risk of harboring PCa. Consequently, in presence of a PCA3 score, these nomograms may be safely used to assist clinicians when prostate biopsy is contemplated.     

Prospective Evaluation of an Extended 21-Core Biopsy Scheme as Initial Prostate Cancer Diagnostic Strategy

Background

The debate on the optimal number of prostate biopsy core samples that should be taken as an initial strategy is open.

Objective

To prospectively evaluate the diagnostic yield of a 21-core biopsy protocol as an initial strategy for prostate cancer (PCa) detection.

Design, setting, and participants

During 10 yr, 2753 consecutive patients underwent a 21-core biopsy scheme for their first set of biopsy specimens.

Intervention

All patients underwent a standardized 21-core protocol with cores mapped for location.

Outcome measurements and statistical analysis

The PCa detection rate of each biopsy scheme (6, 12, or 21 cores) was compared using a McNemar test. Predictive factors of the diagnostic yield achieved by a 21-core scheme were studied using logistic regression analyses.

Results and limitations

PCa detection rates using 6 sextant biopsies, 12 cores, and 21 cores were 32.5%, 40.4%, and 43.3%, respectively. The 12-core procedure improved the cancer detection rate by 19.4% (p = 0.004), and the 21-biopsy scheme improved the rate by 6.7% overall (p < 0.001). The six far lateral cores were the most efficient in terms of detection rate. The diagnostic yield of the 21-core protocol was >10% in prostates with volume >70 ml, in men with a prostate-specific antigen level < 4 ng/ml, with a prostate-specific antigen density (PSAD) <0.20 ng/ml per gram. A PSAD <0.20 ng/ml per gram was the strongest independent predictive factor of the diagnostic yield offered by the 21-core scheme (p < 0.001). The 21-core protocol significantly increased the rate of PCa eligible for active surveillance (62.5% vs 48.4%; p = 0.036) than those detected by a 12-core scheme without statistically increasing the rate of insignificant PCa (p = 0.503).

Conclusions

A 21-core biopsy scheme improves significantly the PCa detection rate compared with a 12-core protocol. We identified a cut-off PSAD (0.20 ng/ml per gram) below which an extended 21-core scheme might be systematically proposed to significantly improve the overall detection rate without increasing the rate of detected insignificant PCa.