A Calculator for Prostate Cancer Risk 4 Years After an Initially Negative Screen: Findings from ERSPC Rotterdam

Background

Inconclusive test results often occur after prostate-specific antigen (PSA)–based screening for prostate cancer (PCa), leading to uncertainty on whether, how, and when to repeat testing.

Objective

To develop and validate a prediction tool for the risk of PCa 4 yr after an initially negative screen.

Design, setting, and participants

We analyzed data from 15 791 screen-negative men aged 55–70 yr at the initial screening round of the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer.

Outcome measurements and statistical analysis

Follow-up and repeat screening at 4 yr showed either no PCa, low-risk PCa, or potentially high-risk PCa (defined as clinical stage >T2b and/or biopsy Gleason score ≥7 and/or PSA ≥10.0 ng/ml). A multinomial logistic regression analysis included initial screening data on age, PSA, digital rectal examination (DRE), family history, prostate volume, and having had a previous negative biopsy. The 4-yr risk predictions were validated with additional follow-up data up to 8 yr after initial screening.

Results and limitations

Positive family history and, especially, PSA level predicted PCa, whereas a previous negative biopsy or a large prostate volume reduced the likelihood of future PCa. The risk of having PCa 4 yr after an initially negative screen was 3.6% (interquartile range: 1.0–4.7%). Additional 8-yr follow-up data confirmed these predictions. Although data were based on sextant biopsies and a strict protocol-based biopsy indication, we suggest that men with a low predicted 4-yr risk (eg, ≤1.0%) could be rescreened at longer intervals or not at all, depending on competing risks, while men with an elevated 4-yr risk (eg, ≥5%) might benefit from immediate retesting. These findings need to be validated externally.

Conclusions

This 4-yr future risk calculator, based on age, PSA, DRE, family history, prostate volume, and previous biopsy status, may be a promising tool for reducing uncertainty, unnecessary testing, and overdiagnosis of PCa.     

Prostate cancer detection and dutasteride: utility and limitations of prostate-specific antigen in men with previous negative biopsies

Context

We addressed the question whether the change of serum prostate-specific antigen (PSA) in men who use 5α-reductase inhibitor (5-ARI) dutasteride is sensitive for the detection of aggressive prostate cancer (PCa).

Objective

The case of a man using dutasteride diagnosed with Gleason 7 transition zone cancer at biopsy indicated by a rising PSA is described. The following issues are discussed: (1) Is a rise of PSA in patients using dutasteride predictive of aggressive PCa in men with prior negative biopsies? (2) Is it safe not to biopsy men using dutasteride who do not show a rising PSA? (3) How can we avoid potentially unnecessary biopsies in men using dutasteride without a rising PSA?

Evidence acquisition

We reviewed the recent literature addressing our objective that relates to two studies: the Prostate Cancer Prevention Trial and the Reduction by Dutasteride of Prostate Cancer Events trial.

Evidence synthesis

In men using dutasteride, the positive predictive value/detection rate of Gleason 7–10 PCa is 13.2% and 4.0% for men with and without a rising PSA, respectively. However, a substantial proportion of Gleason 7–10 cases (42.9%) would be missed if a rising PSA was used as the only biopsy indication. Currently available data do not provide selective mechanisms to diagnose these cancers.

Conclusions

A rising PSA for a patient using dutasteride should be an indication for prostate biopsies. Currently, in the case of stable PSA a biopsy may still be considered. Options for a selective approach are therefore suggested in this review to avoid unnecessary biopsies and to achieve a more selective PCa detection in men on 5-ARI treatment.     

A Risk-Based Strategy Improves Prostate-Specific Antigen–Driven Detection of Prostate Cancer

Background

Screening for prostate cancer (PC) is controversial due to uncertainties about its efficiency.

Objective

We aimed to develop strategies to reduce the number of unnecessary biopsies while still detecting most clinically important PC cases.

Design, setting, and participants

In 1850 men initially screened and biopsied (prostate-specific antigen [PSA] value ≥3.0 ng/ml) in the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer, we calculated both the probability of having a positive lateralized sextant biopsy [P(biop+)] and the probability of having an indolent cancer [P(ind)] if PC was detected at biopsy (n = 541). Analyses of repeat screening included 225 cancers in 1201 men.

Interventions

The P(biop+) was based on applying a logistic regression model that included ultrasound volume, digital rectal exam, and transrectal ultrasound in addition to the PSA value. The P(ind) was based on a recently validated nomogram.

Measurements and limitations

At initial screening the fraction of positive biopsies was 29% (541 of 1850). Applying an additional P(biop+) cut-off of 12.5% implied that 613 of the 1850 men (33%) would not have been biopsied. This would result in an increase in the positive predictive value (PPV) to 38% (468 of 1237). At repeat screening a similar P(biop+) cut-off would result in an increase in the PPV from 19% (225 of 1201) to 25% (188 of 760). Thirteen percent of PC cases would not have been diagnosed, of which 70% (initial screening) and 81% (repeat screening) could be considered as potentially indolent. None of the deadly PC cases would have been missed. A PSA cut-off of ≥4.0 ng/ml resulted in similar numbers of biopsied cases saved but considerably higher numbers of missed diagnoses.

Conclusions

An individualized screening algorithm using other available prebiopsy information in addition to PSA level can result in a considerable reduction of unnecessary biopsies. Very few important PC cases, for which diagnosis at a subsequent screening visit might be too late for treatment with curative intent, would be missed.     

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.     

A panel of TMPRSS2:ERG fusion transcript markers for urine-based prostate cancer detection with high specificity and sensitivity

Background

The TMPRSS2:ERG fusion is both prevalent and unique to prostate cancer (PCa) and has great potential for noninvasive diagnosis of PCa in bodily fluids.

Objectives

To evaluate the specificity and sensitivity of the TMPRSS2:ERG fusion in urine from diverse clinical contexts and to explore potential clinical applications.

Design, setting, and participants

A total of 101 subjects were enrolled in 2008 from urologic oncology clinics to form three study groups: 44 PCa free, 46 confirmed PCa, and 11 negative prostate biopsies. The PCa-free group included females, healthy young men, and post–radical prostatectomy (RP) patients. The confirmed PCa group was composed of patients under active surveillance, scheduled for treatment, or with metastatic disease.

Measurements

Urine was collected after attentive digital rectal exam (DRE) and coded to blind group allocation for laboratory test. RNA from urine sediments was analyzed using a panel of four TMPRSS2:ERG fusion markers with quantitative polymerase chain reaction (qPCR).

Results and limitations

Our fusion markers demonstrated very high technical specificity and sensitivity for detecting a single fusion-positive cancer cell (VCaP) in the presence of at least 3000 cells in urine sediments. In clinical analysis, there were no fusion-positive samples in the PCa-free group (0 of 44 samples), while there were 16 of 46 (34.8%) fusion-positive samples in the confirmed PCa group. The fusion incidence varied significantly among the three PCa subgroups. The clinical sensitivity increased to 45.4% in cancer patients prior to treatments. The fusion markers were detected in 2 of 11 (18.2%) biopsy-negative patients, suggesting potentially false negative biopsies. This study is not prospective and is limited in sample sizes.

Conclusions

Our novel panel of TMPRSS2:ERG fusion markers provided a very specific and sensitive tool for urine-based detection of PCa. Theses markers can potentially be used to diagnose patients with PCa who have negative biopsies.     

Sarcosine in Urine after Digital Rectal Examination Fails as a Marker in Prostate Cancer Detection and Identification of Aggressive Tumours

Background

Sarcosine in urine was recently suggested to be a promising tool in prostate cancer (PCa) diagnostics.

Objective

To reevaluate sarcosine as a potential biomarker for early PCa detection and for prediction of tumour aggressiveness.

Design, setting, and participants

Sarcosine was measured in urine samples from 106 PCa patients and 33 patients with no evidence of malignancy (NEM), confirmed by 8–12 core prostate biopsies, after standardised digital rectal examination, as well as from 12 healthy men and women. The results were related to the clinicopathologic data on prostate volume, tumour stage, Gleason score, and prostate specific antigen (PSA).

Measurements

Sarcosine in urine was determined by gas chromatography-mass spectrometry using a commercial amino acid assay and was normalised to urine creatinine. Nonparametric statistical tests and receiver operating characteristics (ROC) analyses were performed to assess the diagnostic performance.

Results and limitations

The median sarcosine-creatinine ratio in urine was 13% lower in PCa than in NEM patients. Sarcosine values were not associated with tumour stage (pT2 vs pT3) or grade (Gleason score <7 vs ≥7). ROC analyses proved that the discrimination between PCa and NEM patients was not improved by sarcosine in comparison with total PSA, but it was significantly worse than the percent free PSA. The higher proportion of PCa than NEM patients can be considered a limitation of this study.

Conclusions

Sarcosine in urine after rectal digital examination cannot be considered as a suitable marker to differentiate between patients with and without PCa.     

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.     

Age-Specific Risk of Incident Prostate Cancer and Risk of Death from Prostate Cancer Defined by the Number of Affected Family Members

Background

The thorough assessment of familial prostate cancer (PCa) risk is as important as ever to provide a basis for clinical counselling and screening recommendations.

Objective

Our aim was to determine the age-specific risks of PCa and the risk of death from PCa according to the number and the age of affected first-degree relatives.

Design, setting, and participants

The nationwide Swedish Family-Cancer Database includes a record of >11.8 million individuals and their cancers from 1958 to 2006. All men from the database with identified parents (>3.9 million individuals) were followed between 1961 and 2006. The study included 26 651 PCa patients, of whom 5623 were familial.

Measurements

The age-specific hazard ratios (HRs) of PCa and the HRs of death from PCa were calculated according to the number and age of affected fathers and brothers.

Results and limitations

The HRs of PCa diagnosis increased with the number of affected relatives and decreased with increasing age. The highest HRs were observed for men <65 yr of age with three affected brothers (HR: approximately 23) and the lowest for men between 65 and 74 yr of age with an affected father (HR: approximately 1.8). The HRs increased with decreasing paternal or fraternal diagnostic age. The pattern of the risk of death from familial PCa was similar to the incidence data.

Conclusions

The present results should guide clinical counselling and demonstrate the vast increases in risk when multiple first-degree relatives are affected.     

Prospective Study of Diagnostic Accuracy Comparing Prostate Cancer Detection by Transrectal Ultrasound–Guided Biopsy Versus Magnetic Resonance (MR) Imaging with Subsequent MR-guided Biopsy in Men Without Previous Prostate Biopsies

Background

The current diagnosis of prostate cancer (PCa) uses transrectal ultrasound–guided biopsy (TRUSGB). TRUSGB leads to sampling errors causing delayed diagnosis, overdetection of indolent PCa, and misclassification. Advances in multiparametric magnetic resonance imaging (mpMRI) suggest that imaging and selective magnetic resonance (MR)–guided biopsy (MRGB) may be superior to TRUSGB.

Objective

To compare the diagnostic efficacy of the magnetic resonance imaging (MRI) pathway with TRUSGB.

Design, setting, and participants

A total of 223 consecutive biopsy-naive men referred to a urologist with elevated prostate-specific antigen participated in a single-institution, prospective, investigator-blinded, diagnostic study from July 2012 through January 2013.

Intervention

All participants had mpMRI and TRUSGB. Men with equivocal or suspicious lesions on mpMRI also underwent MRGB.

Outcome measurements and statistical analysis

The primary outcome was PCa detection. Secondary outcomes were histopathologic details of biopsy and radical prostatectomy specimens, adverse events, and MRI reader performance. Sensitivity, specificity, negative predictive values (NPVs), and positive predictive values were estimated and basic statistics presented by number (percentage) or median (interquartile range).

Results and limitations

Of 223 men, 142 (63.7%) had PCa. TRUSGB detected 126 cases of PCa in 223 men (56.5%) including 47 (37.3%) classed as low risk. MRGB detected 99 cases of PCa in 142 men (69.7%) with equivocal or suspicious mpMRI, of which 6 (6.1%) were low risk. The MRGB pathway reduced the need for biopsy by 51%, decreased the diagnosis of low-risk PCa by 89.4%, and increased the detection of intermediate/high-risk PCa by 17.7%. The estimated NPVs of TRUSGB and MRGB for intermediate/high-risk disease were 71.9% and 96.9%, respectively. The main limitation is the lack of long follow-up.

Conclusions

We found that mpMRI/MRGB reduces the detection of low-risk PCa and reduces the number of men requiring biopsy while improving the overall rate of detection of intermediate/high-risk PCa.

Patient summary

We compared the results of standard prostate biopsies with a magnetic resonance (MR) image–based targeted biopsy diagnostic pathway in men with elevated prostate-specific antigen. Our results suggest patient benefits of the MR pathway. Follow-up of negative investigations is required.     

Effect of dutasteride on prostate biopsy rates and the diagnosis of prostate cancer in men with lower urinary tract symptoms and enlarged prostates in the Combination of Avodart and Tamsulosin trial

Background

A 23% relative risk reduction (RRR) in prostate cancer (PCa) was shown in men receiving dutasteride in the 4-yr Reduction by Dutasteride of Prostate Cancer Events study, in whom biopsies were protocol dependent.

Objective

Our aim was to explore PCa risk reduction in men with benign prostatic hyperplasia (BPH) from the Combination of Avodart and Tamsulosin (CombAT) study, in which biopsies were undertaken for cause.

Design, setting, and participants

CombAT was a 4-yr randomized double-blind parallel group study in 4844 men ≥50 yr of age with clinically diagnosed moderate to severe BPH, International Prostate Symptom Score ≥12, prostate volume ≥30 ml, and serum prostate-specific antigen (PSA) 1.5–10 ng/ml. Men underwent annual PSA measurement and digital rectal examination (DRE), and prostate biopsies were performed for cause.

Intervention

All patients took tamsulosin 0.4 mg/d, dutasteride 0.5 mg/d, or a combination of both.

Measurements

The primary end point was incidence of PCa. Secondary end points included postbaseline prostate biopsy rates and Gleason score of cancers.

Results and limitations

Dutasteride (alone or in combination with tamsulosin) was associated with a 40% RRR of PCa diagnosis compared with tamsulosin monotherapy (95% confidence interval, 16–57%; p = 0.002) and a 40% reduction in the likelihood of biopsy. There were similar reductions in low- and high-grade Gleason score cancers. The biopsy rate in the groups receiving dutasteride trended toward a higher diagnostic yield (combination: 29%, dutasteride: 28%, tamsulosin: 24%). One limitation was the lack of a standardized approach to PCa diagnosis and grading.

Conclusions

Dutasteride, alone or in combination with tamsulosin, significantly reduced the relative risk of PCa diagnosis in men with BPH undergoing annual DRE and PSA screening. Consistent with the increased usefulness of PSA for PCa detection, men receiving dutasteride had a numerically lower biopsy rate and higher yield of PCa on biopsy.

Trial registration

Clinicaltrials.gov identifier: NCT00090103 (http://www.clinicaltrials.gov/ct2/show/NCT00090103).     

Prostate Cancer Tumour Features on Template Prostate-mapping Biopsies: Implications for Focal Therapy

Background

Focal therapy is being offered as a viable alternative for men with localised prostate cancer (PCa), but it is unclear which men may be suitable.

Objective

To determine the proportion of men with localised PCa who are potentially suitable for focal therapy.

Design, setting, and participants

Our institutional transperineal template prostate-mapping (TTPM) biopsy registry of 377 men from 2006 to 2010 identified 291 consecutive men with no prior treatment.

Intervention

TTPM biopsies using a 5-mm sampling frame.

Outcome measurements and statistical analysis

Suitability for focal therapy required the cancer to be (1) unifocal, (2) unilateral, (3) bilateral/bifocal with at least one neurovascular bundle avoided, or (4) bilateral/multifocal with one dominant index lesion and secondary lesions with Gleason ≤3 + 3 and cancer core involvement ≤3 mm. Binary logistic regression modelling was used to determine variables predictive for focal therapy suitability.

Results and limitations

The median age was 61 yr, and the median prostate-specific antigen was 6.8 ng/ml. The median total was 29 cores, with a median of 8 positive cores. Of 239 of 291 men with cancer, 29% (70 men), 60% (144 men), and 8% (20 men) had low-, intermediate-, and high-risk PCa, respectively. Ninety-two percent (220 men) were suitable for one form of focal therapy: hemiablation (22%, 53 men), unifocal ablation (31%, 73 men), bilateral/bifocal ablation (14%, 33 men), and index lesion ablation (26%, 61 men). Binary logistic regression modelling incorporating transrectal biopsy parameters showed no statistically significant predictive variable. When incorporating TTPM parameters, only T stage was a significant negative predictor for suitability (p = 0.001) (odds ratio: 0.001 [95% confidence interval, 0.000–0.048]). Limitations of the study include potential selection bias caused by tertiary referral practise and lack of long-term results on focal therapy efficacy.

Conclusions

Focal therapy requires an accurate tool to localise individual cancer lesions. When such a test, TTPM biopsy, was applied to men with low- and intermediate-risk PCa, most of the men were suitable for a tissue preservation strategy.     

Incidence of Prostate Cancer After Termination of Screening in a Population-based Randomised Screening Trial

Background

In a previous publication from the Göteborg randomised screening trial from 2010, biennial prostate-specific antigen (PSA) screening for men ≤69 yr of age was shown to lower prostate cancer (PCa) mortality by 44%. The evidence of the optimal age to stop screening, however, is limited.

Objective

To examine the risk of PCa after the discontinuation of screening.

Design, setting, and participants

In December 1994, 20 000 men in Göteborg, Sweden, between the ages of 50 and 65 yr were randomised to a screening arm (invited biennially to PSA testing) and a control arm (not invited). At the upper age limit (average: 69 yr), a total of 13 423 men (6449 and 6974 in the screening and control arms, respectively) were still alive without PCa. The incidence of PCa hereafter was established by matching with the Western Swedish Cancer Register. Participants were followed until a diagnosis of PCa, death, or final follow-up on June 30, 2012, or for a maximum of 12 yr after the last invitation.

Outcome measurements and statistical analysis

Incidence rates and disease-free survival were calculated with life table models and Kaplan-Meier estimates. A competing risk model was also applied.

Results and limitations

Postscreening, 173 cases of PCa were diagnosed in the screening arm (median follow-up: 4.8 yr) and 371 in the control arm (median follow-up: 4.9 yr). Up to 9 yr postscreening, all risk groups were more commonly diagnosed in the control arm, but after 9 yr the rates in the screening arm caught up, other than those for the low-risk group. PCa mortality also caught up after 9 yr.

Conclusions

Nine years after the termination of PSA testing, the incidence of potentially lethal cancers equals that of nonscreened men. Considering the high PCa mortality rate in men >80 yr of age, a general age of 70 yr to discontinue screening might be too low. Instead, a flexible age to discontinue based on individual risk stratification should be recommended.     

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.     

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.     

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.     

High incidence of prostate cancer detected by saturation biopsy after previous negative biopsy series

Objectives

We explored the yield of saturation biopsy and developed a nomogram predicting the probability of prostate cancer (PCa) on the basis of saturation biopsy.

Materials and methods

Between 2001 and 2004, saturation biopsies (average of 24 cores) were performed in 161 men with persistently elevated prostate specific antigen (PSA) level (median, 9 ng/ml). All had at least two previously negative, eight-core biopsy sessions. PCa predictors on saturation biopsy were integrated within multivariate nomograms.

Results

PCa detection was 41% (n = 66 of 161). PSA density and transition zone volume were the most significant predictors of PCa on saturation biopsy. The accuracy of the nomogram with the best performance characteristics was 72%.

Conclusions

Saturation biopsy may be indicated in men with a persistent suspicion of PCa. High-risk individuals can be identified accurately with our nomogram.     

A New Era of Testosterone and Prostate Cancer: From Physiology to Clinical Implications

Context

Decades-old beliefs regarding androgens and prostate cancer (PCa) have undergone dramatic shifts in light of modern evidence and new theoretical constructs, but considerable confusion remains on this topic, particularly with regard to the use of testosterone therapy in men with any history of PCa.

Objective

To review current literature regarding the relationship of serum testosterone on PCa and in particular the effect of testosterone therapy on PCa progression and recurrence.

Evidence acquisition

A Medline search was conducted to identify all original and review articles assessing the effect of androgens on the prostate and the use of testosterone in men with a history of treated and untreated PCa.

Evidence synthesis

Contrary to traditional teaching, high endogenous serum testosterone does not increase the risk of developing PCa, and low serum testosterone does not protect against PCa. Although limited in size and duration, current studies similarly fail to indicate any increased risk of PCa in men receiving testosterone therapy. These results indicate a finite ability of androgens to stimulate PCa growth (the saturation model). A majority of studies demonstrate an association between low serum testosterone and poor prognostic features of PCa, including high-grade disease, advanced pathologic stage, and increased risk of biochemical recurrence following radical prostatectomy. The prostate-specific antigen-to-testosterone ratio predicted PCa risk in several biopsy studies. Multiple reports of testosterone therapy in men after treatment for localized PCa have shown low or absent recurrence rates. Some men with untreated PCa have received testosterone therapy without evidence for PCa progression.

Conclusions

The long-held belief that PCa risk is related to high serum androgen concentrations can no longer be supported. Current evidence indicates that maximal androgen-stimulated PCa growth is achieved at relatively low serum testosterone concentrations. It may therefore be reasonable to consider testosterone therapy in selected men with PCa and symptomatic hypogonadism.     

Long-term Prostate-specific Antigen Velocity in Improved Classification of Prostate Cancer Risk and Mortality

Background

It remains unclear whether adding long-term prostate-specific antigen velocity (PSAV) to baseline PSA values improves classification of prostate cancer (PCa) risk and mortality in the general population.

Objective

To determine whether long-term PSAV improves classification of PCa risk and mortality in the general population.

Design, setting, and participants

We studied 503 men aged 30–80 yr, with and without PCa, who had repeated PSA measurements over 20 yr and up to 28 yr before PCa diagnosis. These were selected from among 7455 men in the Copenhagen City Heart Study, a prospective, general population study with follow-up from 1981 through 2010. Results were subsequently applied to all 1 351 441 men aged 40–80 yr living in Denmark from 1997 through 2006.

Outcome measurements and statistical analysis

PCa risk and mortality were assessed using Cox regression. Improvement in risk classification was assessed using the net reclassification index (NRI).

Results

Age-adjusted hazard ratios for PCa risk and mortality were 2.7–5.3 and 2.3–3.4, respectively, for long-term PSAV when added to models already including baseline PSA values. For PCa risk and mortality, adding long-term PSAV to models already including baseline PSA values and age yielded continuous NRIs of 98–99% and 56–106%, respectively. Used on a nationwide scale (eg, for men aged 60–64 yr), long-term PSAV >0.35 versus ≤0.35 ng/ml per year appropriately reclassified 128 of 10 000 men with PCa and 8095 of 10 000 men with no PCa. Correspondingly, inappropriately reclassified were 49 of 10 000 men with PCa and 1658 of 10 000 men with no PCa.

Conclusions

Long-term PSAV in addition to baseline PSA value improves classification of PCa risk and mortality. Applying long-term PSAV nationwide, the ratio of appropriately to inappropriately classified men would typically be 5:1.     

Performance of prostate cancer antigen 3 (PCA3) and prostate-specific antigen in Prescreened men: reproducibility and detection characteristics for prostate cancer patients with high PCA3 scores (≥ 100)

Background

Prostate cancer antigen 3 (PCA3) is considered to be prostate cancer (PCa) specific and highly overexpressed in cancer. Therefore a high PCA3 score should result in a high positive predictive value (PPV) and specificity for a positive biopsy.

Objective

Our aim was to reevaluate, retest PCA3, and rebiopsy men with an initial PCA3 ≥100 and no PCa detected and compare the results with a random cohort of men with an initial PCA3 < 100.

Design, setting, and participants

We invited men 63–75 yr of age with a PCA3 ≥100 for retesting and a control group with an initial PCA3 < 100 to participate in the European Randomized Study of Screening for Prostate Cancer, section Rotterdam.

Interventions

Blood and urine sampling were used to determine prostate-specific antigen (PSA) and PCA3. Prostate biopsies were performed if the PSA was ≥2.5 ng/ml and/or the PCA3 score was ≥35.

Measurements

We correlated the initial and reevaluated PCA3 scores. Our assessment of the PPV after rebiopsy was based on the newly determined PCA3 score.

Results and limitations

After a mean study period of 19 mo, more cases of PCa were detected in rebiopsied men with initial PCA3 scores ≥100 than in the controls with PCA3 scores <100 (30.0% vs 18.8%). Combining initial and rebiopsy data resulted in a PPV of 52.2% in men with PCA3 ≥100. Over time, changes in PSA and PCA3 levels were quite different.

Conclusions

In spite of our rescreened population, PPV and specificity were comparable with all reported studies of men with PCA3 scores ≥100. These findings do not explain why these PCA3 scores were excessively high in spite of the absence of biopsy-detectable PCa.     

Tumour Grade,Treatment, and Relative Survival in a Population-based Cohort of Men with Potentially Curable Prostate Cancer

Background

There is insufficient information regarding the benefit of treatment with curative intent for men with localised poorly differentiated prostate cancer (PCa).

Objective

To evaluate relative survival in men with potentially curable PCa in relation to Gleason score (GS) and treatment as practiced in the community at large.

Design, setting, and participants

A population-based study including all men with localised PCa registered in Sweden's National Prostate Cancer Register.

Interventions

Hormonal therapy, watchful waiting, and treatment with curative intent.

Measurements

The ratio of observed deaths to expected deaths, determined from survival in the general male population of the same age, was assessed using Poisson regression analysis, with GS and treatment as covariates. Interaction between GS and treatment was tested in a multivariate Cox proportional hazard analysis.

Results and limitations

A total of 31 903 men with potentially curable tumour (T1–T3, N0/NX, M0/MX, age <75 yr, and prostate-specific antigen [PSA] <20 ng/ml) were identified. GS was recorded for 28 454 of these men. Some 19 606 men (60.8%) were treated with curative intent, and 12 645 men (39.2%) were given either hormonal treatment or expectant management. The ratios between observed and expected survival gradually increased for men with GS 10, with GS to 3.3 for men treated conservatively and to 1.4 for men treated with curative intent. There was a significant interaction between GS and treatment, with a relatively greater benefit from treatment with curative intent for men with high-grade tumours. The results have to be interpreted with some caution, as there was no randomisation between the treatment groups.

Conclusions

Survival for men with well-differentiated tumours is close to that of the general population, regardless of treatment, but the outcome is dismal for men with poorly differentiated tumours, whichever treatment is applied. Nevertheless, men with poorly differentiated tumours benefit more from curative treatment than do men with well- differentiated tumours.