Exploring ethnic differences in the distribution of blood test results in healthy adult populations to inform earlier cancer detection: a systematic review.

BACKGROUND: In primary care, health professionals use blood tests to investigate nonspecific presentations to inform referral decisions. Reference ranges for the commonly used blood tests in western countries were developed in predominately White populations, and so may perform differently when applied to non-White populations. Knowledge of ethnic variation in blood test results in healthy/general populations could help address ethnic inequalities in cancer referral for diagnosis and outcomes. OBJECTIVE: This systematic review explored evidence of ethnic differences in the distribution of selected blood test results among healthy/general populations to inform future research aimed at addressing inequalities in cancer diagnosis. METHODS: We searched PubMed and EMBASE to identify studies reporting measures of haemoglobin, MCV, calcium, albumin, platelet count, and CRP in nondiseased adults from at least 2 different ethnic groups. Two reviewers independently screened studies, completed data extraction and quality assessment using an adapted Newcastle-Ottawa scale. Participants were stratified into White, Black, Asian, Mixed, and Other groups. Data were synthesised narratively and meta-analyses were conducted where possible. RESULTS: A total of 47 papers were included. Black men and women have lower average values of haemoglobin, MCV, and albumin, and higher average values of CRP relative to their White counterparts. Additionally, Black men have lower average haemoglobin than Asian men, whereas Asian women have lower average CRP values when compared with White women. CONCLUSIONS: There is evidence of ethnic differences in average values of haemoglobin, MCV, CRP, and albumin in healthy/general populations. Further research is needed to explore the reasons for these differences. Systematic review registration: CRD42021274580.

Association between patient ethnicity and prostate cancer diagnosis following a prostate-specific antigen test: a cohort study of 730,000 men in primary care in the UK.

BACKGROUND: Black men have higher prostate-specific antigen (PSA) levels and higher prostate cancer incidence and mortality than White men, while Asian men tend to have lower prostate cancer incidence and mortality than White men. Much of the evidence comes from the USA, and information from UK populations is limited. METHODS: This retrospective cohort study used data on patients registered at general practices in England contributing to the Clinical Practice Research Datalink (CPRD) Aurum dataset. Those eligible were men aged 40 and over with a record of ethnicity and a PSA test result recorded between 2010 and 2017 with no prior cancer diagnosis. The aim was to assess the incidence of prostate cancer following a raised PSA test result in men from different ethnic groups. Additionally, incidence of advanced prostate cancer was investigated. Cancer incidence was estimated from multi-level logistic regression models adjusting for potential confounding factors. RESULTS: 730,515 men with a PSA test were included (88.9% White). Black men and men with mixed ethnicity had higher PSA values, particularly for those aged above 60 years. In the year following a raised PSA result (using age-specific thresholds), Black men had the highest prostate cancer incidence at 24.7% (95% CI 23.3%, 26.2%); Asian men had the lowest at 13.4% (12.2%, 14.7%); incidence for White men was 19.8% (19.4%, 20.2%). The peak incidence of prostate cancer for all groups was in men aged 70-79. Incidence of prostate cancer diagnosed at an advanced stage was similar between Black and White men. CONCLUSIONS: More prostate cancer was diagnosed in Black men with a raised PSA result, but rates of advanced prostate cancer were not higher in this group. In this large primary care-based cohort, the incidence of prostate cancer in men with elevated PSA levels increases with increasing age, even when using age-adjusted thresholds, with Black men significantly more likely to be diagnosed compared to White or Asian men. The incidence of advanced stage prostate cancer at diagnosis was similar for Black and White men with a raised PSA result, but lower for Asian men.

Ethnic differences in prostate-specific antigen levels in men without prostate cancer: a systematic review.

INTRODUCTION: Black men are twice as likely to be diagnosed with prostate cancer than White men. Raised prostate-specific antigen (PSA) levels can indicate an increased risk of prostate cancer, however it is not known whether PSA levels differ for men of different ethnic groups. METHODS: PubMed and Embase were searched to identify studies that reported levels of PSA for men of at least two ethnic groups without a prostate cancer diagnosis or symptoms suggestive of prostate cancer. An adaptation of the Newcastle-Ottawa scale was used to assess risk of bias and study quality. Findings were stratified into the following broad ethnic groups: White, Black, Asian, Hispanic, and Other. Data were analysed in a narrative synthesis due to the heterogeneity of reported PSA measures and methods in the included studies. RESULTS: A total of 654 197 males from 13 studies were included. By ethnicity, this included 536 201 White (82%), 38 287 Black (6%), 38 232 Asian (6%), 18 029 Pacific Island (3%), 13 614 Maori (2%), 8 885 Hispanic (1%), and 949 Other (<1%) men aged ≥40 years old. Black men had higher PSA levels than White men, and Hispanic men had similar levels to White men and lower levels than Black men. CONCLUSIONS: Black men without prostate cancer have higher PSA levels than White or Hispanic men, which reflects the higher rates of prostate cancer diagnosis in Black men. Despite that, the diagnostic accuracy of PSA for prostate cancer for men of different ethnic groups is unknown, and current guidance for PSA test interpretation does not account for ethnicity. Future research needs to determine whether Black men are diagnosed with similar rates of clinically significant prostate cancer to White men, or whether raised PSA levels are contributing to overdiagnosis of prostate cancer in Black men.

ProDiet: A Phase II Randomized Placebo-controlled Trial of Green Tea Catechins and Lycopene in Men at Increased Risk of Prostate Cancer.

Epidemiologic studies suggest that diet can alter prostate cancer risk. This study aimed to establish the feasibility and acceptability of dietary modification in men at increased risk of prostate cancer. Men were invited with a PSA level of 2.0-2.95 ng/mL or 3.0-19.95 ng/mL with negative prostate biopsies. Randomization (3 × 3 factorial design) to daily green tea and lycopene: green tea drink (3 cups, unblinded) or capsules [blinded, 600 mg flavan-3-ol ()-epigallocatechin-3-gallate (EGCG) or placebo] and lycopene-rich foods (unblinded) or capsules (blinded, 15 mg lycopene or placebo) for 6 months. Primary endpoints were randomization rates and intervention adherence (blinded assessment of metabolites) at 6 months with secondary endpoints of acceptability (from interviews), safety, weight, blood pressure, and PSA. A total of 133 of 469 (28.4%) men approached agreed to be randomized and 132 were followed-up (99.2%). Mean lycopene was 1.28 [95% confidence intervals (CI), 1.09-1.50, P = 0.003] times higher in the lycopene capsule group and 1.42 (95% CI, 1.21-1.66; P < 0.001) times higher in the lycopene-enriched diet group compared with placebo capsules. Median EGCG was 10.7 nmol/L (95% CI, 7.0-32.0) higher in in the active capsule group and 20.0 nmol/L (95% CI, 0.0-19.0) higher in the green tea drink group compared with placebo capsules (both P < 0.001). All interventions were acceptable and well tolerated although men preferred the capsules. Dietary prevention is acceptable to men at risk of prostate cancer. This intervention trial demonstrates that a chemoprevention clinical trial is feasible. Cancer Prev Res; 11(11); 687-96. ©2018 AACR.

Patient-reported outcomes in the ProtecT randomized trial of clinically localized prostate cancer treatments: study design, and baseline urinary, bowel and sexual function and quality of life.

OBJECTIVES: To present the baseline patient-reported outcome measures (PROMs) in the Prostate Testing for Cancer and Treatment (ProtecT) randomized trial comparing active monitoring, radical prostatectomy and external-beam conformal radiotherapy for localized prostate cancer and to compare results with other populations. MATERIALS AND METHODS: A total of 1643 randomized men, aged 50-69 years and diagnosed with clinically localized disease identified by prostate-specific antigen (PSA) testing, in nine UK cities in the period 1999-2009 were included. Validated PROMs for disease-specific (urinary, bowel and sexual function) and condition-specific impact on quality of life (Expanded Prostate Index Composite [EPIC], 2005 onwards; International Consultation on Incontinence Questionnaire-Urinary Incontinence [ICIQ-UI], 2001 onwards; the International Continence Society short-form male survey [ICSmaleSF]; anxiety and depression (Hospital Anxiety and Depression Scale [HADS]), generic mental and physical health (12-item short-form health survey [SF-12]; EuroQol quality-of-life survey, the EQ-5D-3L) were assessed at prostate biopsy clinics before randomization. Descriptive statistics are presented by treatment allocation and by men's age at biopsy and PSA testing time points for selected measures. RESULTS: A total of 1438 participants completed biopsy questionnaires (88%) and 77-88% of these were analysed for individual PROMs. Fewer than 1% of participants were using pads daily (5/754). Storage lower urinary tract symptoms were frequent (e.g. nocturia 22%, 312/1423). Bowel symptoms were rare, except for loose stools (16%, 118/754). One third of participants reported erectile dysfunction (241/735) and for 16% (118/731) this was a moderate or large problem. Depression was infrequent (80/1399, 6%) but 20% of participants (278/1403) reported anxiety. Sexual function and bother were markedly worse in older men (65-70 years), whilst urinary bother and physical health were somewhat worse than in younger men (49-54 years, all P < 0.001). Bowel health, urinary function and depression were unaltered by age, whilst mental health and anxiety were better in older men (P < 0.001). Only minor differences existed in mental or physical health, anxiety and depression between PSA testing and biopsy assessments. CONCLUSION: The ProtecT trial baseline PROMs response rates were high. Symptom frequencies and generic quality of life were similar to those observed in populations screened for prostate cancer and control subjects without cancer.

Contemporary accuracy of death certificates for coding prostate cancer as a cause of death: Is reliance on death certification good enough? A comparison with blinded review by an independent cause of death evaluation committee.

BACKGROUND: Accurate cause of death assignment is crucial for prostate cancer epidemiology and trials reporting prostate cancer-specific mortality outcomes. METHODS: We compared death certificate information with independent cause of death evaluation by an expert committee within a prostate cancer trial (2002-2015). RESULTS: Of 1236 deaths assessed, expert committee evaluation attributed 523 (42%) to prostate cancer, agreeing with death certificate cause of death in 1134 cases (92%, 95% CI: 90%, 93%). The sensitivity of death certificates in identifying prostate cancer deaths as classified by the committee was 91% (95% CI: 89%, 94%); specificity was 92% (95% CI: 90%, 94%). Sensitivity and specificity were lower where death occurred within 1 year of diagnosis, and where there was another primary cancer diagnosis. CONCLUSIONS: UK death certificates accurately identify cause of death in men with prostate cancer, supporting their use in routine statistics. Possible differential misattribution by trial arm supports independent evaluation in randomised trials.

Validating the use of Hospital Episode Statistics data and comparison of costing methodologies for economic evaluation: an end-of-life case study from the Cluster randomised triAl of PSA testing for Prostate cancer (CAP).

OBJECTIVES: To evaluate the accuracy of routine data for costing inpatient resource use in a large clinical trial and to investigate costing methodologies. DESIGN: Final-year inpatient cost profiles were derived using (1) data extracted from medical records mapped to the National Health Service (NHS) reference costs via service codes and (2) Hospital Episode Statistics (HES) data using NHS reference costs. Trust finance departments were consulted to obtain costs for comparison purposes. SETTING: 7 UK secondary care centres. POPULATION: A subsample of 292 men identified as having died at least a year after being diagnosed with prostate cancer in Cluster randomised triAl of PSA testing for Prostate cancer (CAP), a long-running trial to evaluate the effectiveness and cost-effectiveness of prostate-specific antigen (PSA) testing. RESULTS: Both inpatient cost profiles showed a rise in costs in the months leading up to death, and were broadly similar. The difference in mean inpatient costs was £899, with HES data yielding ∼8% lower costs than medical record data (differences compatible with chance, p=0.3). Events were missing from both data sets. 11 men (3.8%) had events identified in HES that were all missing from medical record review, while 7 men (2.4%) had events identified in medical record review that were all missing from HES. The response from finance departments to requests for cost data was poor: only 3 of 7 departments returned adequate data sets within 6 months. CONCLUSIONS: Using HES routine data coupled with NHS reference costs resulted in mean annual inpatient costs that were very similar to those derived via medical record review; therefore, routinely available data can be used as the primary method of costing resource use in large clinical trials. Neither HES nor medical record review represent gold standards of data collection. Requesting cost data from finance departments is impractical for large clinical trials. TRIAL REGISTRATION NUMBER: ISRCTN92187251; Pre-results.

Active monitoring, radical prostatectomy, or radiotherapy for localised prostate cancer: study design and diagnostic and baseline results of the ProtecT randomised phase 3 trial.

BACKGROUND: Prostate cancer is a major public health problem with considerable uncertainties about the effectiveness of population screening and treatment options. We report the study design, participant sociodemographic and clinical characteristics, and the initial results of the testing and diagnostic phase of the Prostate testing for cancer and Treatment (ProtecT) trial, which aims to investigate the effectiveness of treatments for localised prostate cancer. METHODS: In this randomised phase 3 trial, men aged 50-69 years registered at 337 primary care centres in nine UK cities were invited to attend a specialist nurse appointment for a serum prostate-specific antigen (PSA) test. Prostate biopsies were offered to men with a PSA concentration of 3·0 µg/L or higher. Consenting participants with clinically localised prostate cancer were randomly assigned to active monitoring (surveillance strategy), radical prostatectomy, or three-dimensional conformal external-beam radiotherapy by a computer-generated allocation system. Randomisation was stratified by site (minimised for differences in participant age, PSA results, and Gleason score). The primary endpoint is prostate cancer mortality at a median 10-year follow-up, ascertained by an independent committee, which will be analysed by intention to treat in 2016. This trial is registered with ClinicalTrials.gov, number NCT02044172, and as an International Standard Randomised Controlled Trial, number ISRCTN20141297. FINDINGS: Between Oct 1, 2001, and Jan 20, 2009, 228,966 men were invited to attend an appointment with a specialist nurse. Of the invited men, 100,444 (44%) attended their initial appointment and 82,429 (82%) of attenders had a PSA test. PSA concentration was below the biopsy threshold in 73,538 (89%) men. Of the 8566 men with a PSA concentration of 3·0-19·9 µg/L, 7414 (87%) underwent biopsies. 2896 men were diagnosed with prostate cancer (4% of tested men and 39% of those who had a biopsy), of whom 2417 (83%) had clinically localised disease (mostly T1c, Gleason score 6). With the addition of 247 pilot study participants recruited between 1999 and 2001, 2664 men were eligible for the treatment trial and 1643 (62%) agreed to be randomly assigned (545 to active monitoring, 545 to radiotherapy, and 553 to radical prostatectomy). Clinical and sociodemographic characteristics of randomly assigned participants were balanced across treatment groups. INTERPRETATION: The ProtecT trial randomly assigned 1643 men with localised prostate cancer to active monitoring, radiotherapy, or surgery. Participant clinicopathological features are more consistent with contemporary patient characteristics than in previous prostate cancer treatment trials. FUNDING: UK National Institute for Health Research Health Technology Assessment Programme.

Men with prostate cancer make positive dietary changes following diagnosis and treatment.

PURPOSE: Few studies have measured dietary changes made among men diagnosed with prostate cancer (PC) without formal dietary interventions, yet they may offer insight into the needs of PC survivors. This study examined dietary changes in men before and after treatment for PC within the prostate testing for cancer and treatment randomized trial. METHODS: This was a prospective cohort study in community-based men aged 50-69 tested for PC in nine UK areas. 3,935 men completed food frequency questionnaires before diagnosis and 678 with localized PC repeated the questionnaire 1 year later (response 82.7 %). RESULTS: Men subsequently diagnosed with or without PC all consumed similar diets before diagnosis. Diagnosis of PC led to dietary changes, with 234 (34.7 %) men eating more fresh tomatoes (p < 0.0001) and 156 (23.5 %) more tomato products (p = 0.01). 271 (40.0 %) men consumed more protein (p < 0.0001) and 193 (28.6 %) more fruit/vegetable juice (p < 0.0001). Fewer macronutrients were obtained from dairy products (p < 0.01). Men undergoing active monitoring increased their fruit/vegetable juice intake after diagnosis (p = 0.0023) more than men who had surgery or radiotherapy. CONCLUSIONS: Around one-third of men spontaneously adopted a healthier diet and also consumed more 'prostate-healthy' foods following a diagnosis of PC. Dietary choices also differed by radical or monitoring treatments, indicating that men undergoing active surveillance may be more likely to pursue dietary changes as an adjunct therapy. PC survivors can adopt healthier diets, thus providing clinicians with opportunities to support PC survivorship by providing targeted advice beneficial to general and potentially prostate-specific health.

Seasonal variation in prostate-specific antigen levels: a large cross-sectional study of men in the UK.

OBJECTIVE: • To assess whether a seasonal change in prostate specific antigen (PSA) levels can be detected in men recruited to a large clinical trial. PATIENTS AND METHODS: • A total of 66 969 men aged 50-69 years were drawn from a large study conducted at general practices across the UK between 2002 and 2007. • Trigonometric algorithms and regression methods were used to assess the relationship between the time of year and serum PSA and blood pressure measurements. • We obtained local daily mean temperatures and hours of sunlight per day to assess whether these factors were potential mechanisms for seasonal variation in PSA levels or blood pressure. • The proportion of participants who would be considered clinically at risk according to their PSA or blood pressure measurement, by month, was also assessed. • The strength of associations between time of year and blood pressure were used to reinforce conclusions from the PSA models. RESULTS: • There was no relationship between time of year and PSA levels (P= 0.11) or between climate and PSA levels (P= 0.42). • No difference was found in the prevalence of clinically raised PSA content by month (P= 0.50). • This lack of an association with PSA content was despite our data being sufficient to provide clear evidence of an association between blood pressure and time of year (systolic P < 0.001; diastolic P < 0.001), and to show that this association was largely explained by climatic factors (temperature and sunlight). CONCLUSION: • There was no pattern in PSA levels by time of year, air temperature or levels of sunlight in this cohort, so there is no need to take these factors into account when reviewing PSA results.

A Peer Review Intervention for Monitoring and Evaluating sites (PRIME) that improved randomized controlled trial conduct and performance.

OBJECTIVE: Good clinical practice (GCP) guidelines emphasize trial site monitoring, although the implementation is unspecified and evidence for benefit is sparse. We aimed to develop a site monitoring process using peer reviewers to improve staff training, site performance, data collection, and GCP compliance. STUDY DESIGN AND SETTING: The Peer Review Intervention for Monitoring and Evaluating sites (PRIME) team observed and gave feedback on trial recruitment and follow-up appointments, held staff meetings, and examined documentation during annual 2-day site visits. The intervention was evaluated in the ProtecT trial, a UK randomized controlled trial of localized prostate cancer treatments (ISRCTN20141297). The ProtecT coordinator and senior nurses conducted three monitoring rounds at eight sites (2004-2007). The process evaluation used PRIME report findings, trial databases, resource use, and a site nurse survey. RESULTS: Adverse findings decreased across all sites from 44 in round 1 to 19 in round 3. Most findings related to protocol adherence or site organizational issues, including improvements in eligibility criteria application and data collection. Staff found site monitoring acceptable and made changes after reviews. CONCLUSION: The PRIME process used observation by peer reviewers to improve protocol adherence and train site staff, which increased trial performance and consistency.

Associations of aspirin, nonsteroidal anti-inflammatory drug and paracetamol use with PSA-detected prostate cancer: findings from a large, population-based, case-control study (the ProtecT study).

Evidence from laboratory studies suggests that chronic inflammation plays an important role in prostate cancer aetiology. This has resulted in speculation that nonsteroidal anti-inflammatory drugs may protect against prostate cancer development. We analysed data from a cross-sectional case-control study (n(cases) = 1,016; n(controls) = 5,043), nested within a UK-wide population-based study that used prostate specific antigen (PSA) testing for identification of asymptomatic prostate cancers, to investigate the relationship of aspirin, nonsteroidal anti-inflammatory drug (NSAID) and paracetamol use with prostate cancer. In conditional logistic regression models accounting for stratum matching on age (5-year age bands) and recruitment centre, use of non-aspirin NSAIDs [odds ratio (OR) = 1.32; 95% confidence interval (CI): 1.04-1.67] or all NSAIDs (OR = 1.25; 95% CI = 1.07-1.47) were positively associated with prostate cancer. There were weaker, not conventionally statistically significant, positive associations of aspirin (OR = 1.13; 95% CI = 0.94-1.36) and paracetamol (OR = 1.20; 95% CI = 0.90-1.60) with prostate cancer. Mutual adjustment for aspirin, non-aspirin NSAIDs or paracetamol made little difference to these results. There was no evidence of confounding by age, family history of prostate cancer, body mass index or self-reported diabetes. Aspirin, NSAID and paracetamol use were associated with reduced serum PSA concentrations amongst controls. Our findings do not support the hypothesis that NSAIDs reduce the risk of PSA-detected prostate cancer. Our conclusions are unlikely to be influenced by PSA detection bias because the inverse associations of aspirin, NSAID and paracetamol use with serum PSA would have attenuated (not generated) the observed positive associations.

Psychological distress and prostate specific antigen levels in men with and without prostate cancer.

The role of psychological distress in the onset and progression of prostate cancer is an under-researched area. We report results from a cohort study in which we have examined the relationship between indices of psychological distress and prostate specific antigen (PSA) levels (a glycoprotein associated with prostatic diseases including cancer) in men with and without prostate cancer and also the relationship between distress and the likelihood of receiving a diagnosis of prostate cancer. Data were obtained from 4886 men who attended PSA testing and biopsy as part of the ProtecT (Prostate testing for cancer and treatment) study (mean age 62years; 98.9% White). Men completed questionnaires measuring anxiety, depression and urinary symptoms at initial PSA testing and again at biopsy when PSA was re-measured. Regardless of the subsequent diagnosis, there was no association between psychological distress scores at initial PSA testing and PSA measured at biopsy. However, analyses pertaining to the relationship between distress and cancer diagnosis showed that men with 'possible' clinical depression at initial PSA testing (n=519/4886) were 23% more likely to have a diagnosis of prostate cancer. These analyses highlight the need for further investigations into the possible role of depressed mood in the onset of prostate cancer and, in particular, research examining the biological basis for these relationships.

Do the risk factors of age, family history of prostate cancer or a higher prostate specific antigen level raise anxiety at prostate biopsy?

To date, little is known of the impact knowledge of personal risk factors has on anxiety in men undergoing biopsy tests for prostate cancer. This analysis explores anxiety scores of men at higher risk due to age, family history of prostate cancer and a higher prostate specific antigen (PSA) level when proceeding from PSA test to prostate biopsy. A prospective cohort of 4198 men aged 50-69 years with a PSA result of >3ng/ml was studied, recruited for the Prostate testing for cancer and Treatment study (ProtecT). Anxiety scores at the time of biopsy were lower in older men (p<0.001). No age group showed an increase in anxiety as the men proceeded from PSA testing to biopsy, although older men did not show the same level of decrease in anxiety as younger men (p=0.035). There was no difference in anxiety scores at biopsy between men with or without a family history of prostate cancer (p=0.68), or between those with a raised PSA of 10-<20ng/ml compared to a PSA result of 3-<10ng/ml (p=0.46). Change in scores since the initial PSA test appeared unaffected by family history (p=0.995) or by PSA result (p=0.76). Within the context of a research study, the increased risk of prostate cancer through older age, having a family history of prostate cancer, or having a significantly elevated PSA level appears to have no detrimental effect on men's anxiety level when proceeding to biopsy.

Factors distinguishing general practitioners who more readily participated in a large randomized trial were identified.

OBJECTIVE: To investigate factors associated with the successful recruitment of general practices to a randomized controlled trial. STUDY DESIGN AND SETTING: Analysis of accrual of primary care centers to a randomized controlled trial in the UK. RESULTS: Those practices promptly agreeing to take part had better target achievement and a higher proportion of white British residents locally. Participating practices had a mean Quality and Outcomes Framework attainment of 92% of the points available, whereas nonparticipating practices achieved 88% (P=0.009). Participating practices were located in areas with a higher proportion of white British residents (mean 89%), in comparison to nonparticipating practices (mean 84%, P=0.004). Reasons given by practices to explain nonparticipation were primarily related to internal factors, with 38% of practices approached saying that they could not participate for such reasons. CONCLUSION: There are some small differences between participating practices and nonparticipants in achievement of government targets and in the local ethnic mix. The primary reason given by practices for nonparticipation was workload or time pressures, with over a third of practices reporting being prevented by issues relating to practice organization. It may be that practices with workload or organizational difficulties require additional support to participate in research.

Detection of prostate cancer in unselected young men: prospective cohort nested within a randomised controlled trial.

OBJECTIVE: To investigate the feasibility of testing for prostate cancer and the prevalence and characteristics of the disease in unselected young men. DESIGN: Prospective cohort nested within a randomised controlled trial, with two years of follow-up. SETTING: Eight general practices in a UK city. PARTICIPANTS: 1299 unselected men aged 45-49. INTERVENTION: Prostate biopsies for participants with a prostate specific antigen level of 1.5 ng/ml or more and the possibility of randomisation to three treatments for those with localised prostate cancer. MAIN OUTCOME MEASURES: Uptake of testing for prostate specific antigen; positive predictive value of prostate specific antigen; and prevalence of prostate cancer, TNM disease stage, and histological grade (Gleason score). RESULTS: 442 of 1299 men agreed to be tested for prostate specific antigen (34%) and 54 (12%) had a raised level. The positive predictive value for prostate specific antigen was 21.3%. Ten cases of prostate cancer were detected (2.3%) with eight having at least two positive results in biopsy cores and three showing perineural invasion. One tumour was of high volume (cT2c), Gleason score 7, with a positive result on digital rectal examination; nine tumours were cT1c, Gleason score 6, and eight had a negative result on digital rectal examination. Five of the nine eligible participants (55%) agreed to be randomised. No biochemical disease progression in the form of a rising prostate specific antigen level occurred in two years of follow-up. CONCLUSIONS: Men younger than 50 will accept testing for prostate cancer but at a much lower rate than older men. Using an age based threshold of 1.5 ng/ml, the prevalence of prostate cancer was similar to that in older men (3.0 ng/ml threshold) and some cancers of potential clinical significance were found. TRIAL REGISTRATION: Current Controlled Trials ISRCTN20141297.