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Training recruiters to randomized trials to facilitate recruitment and informed consent by exploring patients' treatment preferences.

BACKGROUND: Patients' treatment preferences are often cited as barriers to recruitment in randomized controlled trials (RCTs). We investigated how RCT recruiters reacted to patients' treatment preferences and identified key strategies to improve informed decision-making and trial recruitment. METHODS: Audio-recordings of 103 RCT recruitment appointments with 96 participants in three UK multicenter pragmatic RCTs were analyzed using content and thematic analysis. Recruiters' responses to expressed treatment preferences were assessed in one RCT (ProtecT - Prostate testing for cancer and Treatment) in which training on exploring preferences had been given, and compared with two other RCTs where this specific training had not been given. RESULTS: Recruiters elicited treatment preferences similarly in all RCTs but responses to expressed preferences differed substantially. In the ProtecT RCT, patients' preferences were not accepted at face value but were explored and discussed at length in three key ways: eliciting and acknowledging the preference rationale, balancing treatment views, and emphasizing the need to keep an open mind and consider all treatments. By exploring preferences, recruiters enabled participants to become clearer about whether their views were robust enough to be sustained or were sufficiently weak that participation in the RCT became possible. Conversely, in the other RCTs, treatment preferences were often readily accepted without further discussion or understanding the reasoning behind them, suggesting that patients were not given the opportunity to fully consider all treatments and trial participation. CONCLUSIONS: Recruiters can be trained to elicit and address patients' treatment preferences, enabling those who may not have considered trial participation to do so. Without specific guidance, some RCT recruiters are likely to accept initial preferences at face value, missing opportunities to promote more informed decision-making. Training interventions for recruiters that incorporate key strategies to manage treatment preferences, as in the ProtecT study, are required to facilitate recruitment and informed consent. TRIAL REGISTRATION: ProtecT RCT: Current Controlled Trials ISRCTN20141297. The other two trials are registered but have asked to be anonymized.

Associations between an obesity related genetic variant (FTO rs9939609) and prostate cancer risk.

UNLABELLED: Observational studies suggest that obese men have a lower risk of incident prostate cancer, but an increased risk of advanced and fatal cancers. These observations could be due to confounding, detection bias, or a biological effect of obesity. Genetic studies are less susceptible to confounding than observational epidemiology and can suggest how associations between phenotypes (such as obesity) and diseases arise. To determine whether the associations between obesity and prostate cancer are causal, we conducted a genetic association study of the relationship between a single nucleotide polymorphism known to be associated with obesity (FTO rs9939609) and prostate cancer. Data are from a population-based sample of 1550 screen-detected prostate cancers, 1815 age- and general practice matched controls with unrestricted prostate specific antigen (PSA) values and 1175 low-PSA controls (PSA <0.5 ng/ml). The rs9939609 A allele, which was associated with higher BMI in the sample, was inversely associated with overall (odds ratio (OR) versus all controls  = 0.93; 95% confidence interval (CI): 0.85-1.02 p = 0.12 per allele) and low-grade (OR = 0.90; 0.81-0.99 p = 0.03 per allele) prostate cancer risk, but positively associated with high-grade cancer among cases (OR high- versus low-grade cancer  = 1.16; 0.99-1.37 p = 0.07 per allele). Although evidence for these effects was weak, they are consistent with observational data based on BMI phenotypes and suggest that the observed association between obesity and prostate cancer is not due to confounding. Further research should confirm these findings, extend them to other BMI-related genetic variants and determine whether they are due to detection bias or obesity-related hormonal changes. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN20141297.

Stage shift in PSA-detected prostate cancers - effect modification by Gleason score.

OBJECTIVE: This paper aims to investigate whether the stage shift (where more cancers are detected at an earlier stage) in prostate-specific antigen (PSA)-detected cancers differs by Gleason score. METHODS: Between 2002 and 2005, 1514 men aged 50-69 years were identified with prostate cancer following community-based PSA testing as part of the ProtecT study. In the same period, 2021 men aged 50-69 years with clinically diagnosed prostate cancer were registered at a population-based cancer registry in the East of England. Using logistic regression analysis and controlling for age, the odds ratio (OR) for advanced stage (TNM stage T3 and above) prostate cancer among the PSA-detected group was compared with the clinically diagnosed tumours. The evidence that stage shift differs by Gleason score was assessed using the likelihood ratio test for interaction. RESULTS: Advanced stage disease among the PSA-detected cancers was less common than among the clinically detected cancers (OR = 0.47, 95% CI 0.39-0.56). PSA-detected tumours had a substantial shift to earlier-stage disease where the Gleason score was <7 (OR = 0.52; 95% CI 0.36-0.77, P < 0.001) but showed no such shift where the Gleason score was 7 or more (OR = 0.84; 95% CI 0.66-1.07, P = 0.1). There was evidence of interaction between detection mode and Gleason score (P = 0.03). CONCLUSION: The observed stage shift could be partially explained by length bias or overdiagnosis. These findings may have implications on understanding pathways of prostate cancer progression and on identifying potential targets for screening, pending further investigation of complexities of associations between PSA testing, Gleason score, and stage.

Prostate Testing for Cancer and Treatment (ProtecT) feasibility study.

Transrectal ultrasound guided needle electromyography of the urethral sphincter in males.

Needle electromyography (EMG) of the urethral sphincter in males is commonly performed using a transperineal approach. The technique involves transcutaneous insertion of an EMG needle into the sphincter guided by the investigator's finger placed in the rectum. We describe a new method of needle placement into the urethral sphincter in males using transrectal ultrasound (TRUS). With the patient in the left lateral position, the apex of the prostate gland is identified in the longitudinal plane. Using the TRUS biopsy channel, a specially designed long EMG needle is inserted into the sphincter commencing approximately 1.5-2 cm distal to the prostatic apex in an oblique fashion. This method allows precise identification of the site for needle insertion, reducing blind attempts at localization. The transrectal route is much less uncomfortable to patients, potentially improving patient compliance and overall effectiveness of the technique.

ADHERENCE TO DIETARY AND LIFESTYLE RECOMMENDATIONS AND PROSTATE CANCER RISK IN THE PROSTATE TESTING FOR CANCER AND TREATMENT (PROTECT) TRIAL

Validation of the Hospital Episode Statistics Outpatient Dataset in England.

OBJECTIVES: The Hospital Episode Statistics (HES) dataset is a source of administrative 'big data' with potential for costing purposes in economic evaluations alongside clinical trials. This study assesses the validity of coverage in the HES outpatient dataset. METHODS: Men who died of, or with, prostate cancer were selected from a prostate-cancer screening trial (CAP, Cluster randomised triAl of PSA testing for Prostate cancer). Details of visits that took place after 1/4/2003 to hospital outpatient departments for conditions related to prostate cancer were extracted from medical records (MR); these appointments were sought in the HES outpatient dataset based on date. The matching procedure was repeated for periods before and after 1/4/2008, when the HES outpatient dataset was accredited as a national statistic. RESULTS: 4922 outpatient appointments were extracted from MR for 370 men. 4088 appointments recorded in MR were identified in the HES outpatient dataset (83.1%; 95% confidence interval [CI] 82.0-84.1). For appointments occurring prior to 1/4/2008, 2195/2755 (79.7%; 95% CI 78.2-81.2) matches were observed, while 1893/2167 (87.4%; 95% CI 86.0-88.9) appointments occurring after 1/4/2008 were identified (p for difference <0.001). 215/370 men (58.1%) had at least one appointment in the MR review that was unmatched in HES, 155 men (41.9%) had all their appointments identified, and 20 men (5.4%) had no appointments identified in HES. CONCLUSIONS: The HES outpatient dataset appears reasonably valid for research, particularly following accreditation. The dataset may be a suitable alternative to collecting MR data from hospital notes within a trial, although caution should be exercised with data collected prior to accreditation.

The relation between adiposity throughout the life course and variation in IGFs and IGFBPs: evidence from the ProtecT (Prostate testing for cancer and Treatment) study.

OBJECTIVE: Adiposity is positively associated with advanced, metastatic, and fatal prostate cancer. Obesity-related variations in insulin-like growth factors (IGF-I and -II) and their binding proteins (IGFBPs) could underlie these associations. METHODS: We investigated associations of adiposity throughout the life course (determined retrospectively) with serum levels of IGF-I, IGF-II, IGFBP-2 and IGFBP-3 in a population-based study of 1,106 healthy men. RESULTS: IGF-I and IGF-II showed inverted U-shaped associations with adult body mass index (BMI) (p quadratic model = 0.04 and 0.06, respectively), although differences between quartiles with the highest and lowest IGF-I levels were small (no more than 5 ng/ml). IGFBP-2 was strongly inversely related to adult BMI (-22% change per SD increase in BMI; 95% confidence interval (CI) -24% to -19%) and waist circumference (-18% change per SD increase in waist circumference; 95% CI -20% to -15%) (p < 0.001). IGFBP-3 was positively related to BMI (63.5 ng/ml increase per SD increase in BMI; 95% CI -2.69 to 129.8, p = 0.06). IGFBP-2 and IGFBP-3 were strongly related to body shape change from childhood to adulthood, with men who gained the most weight having the lowest IGFBP-2 (9% lower per category body shape change; 95% CI -11% to -7%, p < 0.001) and the highest IGFBP-3 (50 ng/ml increase per category; 95% CI 8 to 92, p = 0.02). CONCLUSIONS: We provide evidence that adiposity and change in body shape through the life course are related to the IGF system, with the largest effect of adiposity being to lower IGFBP-2, a possible marker of insulin resistance. The results suggest that circulating IGF-I levels may not be important mediators of the association of adiposity with aggressive prostate cancer, but the role of IGFBP-2 deserves further investigation.

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.

Genetic variants in the vitamin d receptor are associated with advanced prostate cancer at diagnosis: findings from the prostate testing for cancer and treatment study and a systematic review.

Low levels of plasma vitamin D have been implicated as a possible risk factor for both prostate cancer incidence and advanced disease, and recent phase II trials suggest that vitamin D supplementation might delay progression of prostate cancer. Common polymorphisms in the vitamin D receptor (VDR) are associated with VDR activity and are therefore potentially useful proxies for assessing whether vitamin D is causally related to advanced prostate cancer. We genotyped five well-known VDR polymorphisms in 1,604 men with prostate cancer from the Prostate Testing for Cancer and Treatment study. Our aim was to examine the association between VDR polymorphisms and cancer stage (localized versus advanced) as well as cancer grade (Gleason score <7 versus >or=7). Moreover, we also carried out a systematic review and meta-analysis of 13 similar studies. As a result of our meta-analysis, we revealed three polymorphisms, BsmI, ApaI, and TaqI, associated with high Gleason score with an overall summary odds ratios (95% confidence intervals) of 1.12 (1.00-1.25; bb versus BB + Bb), 1.25 (1.02-1.53; aa versus AA + Aa), and 0.82 (0.69-0.98; Tt + tt versus TT), respectively. The haplotype analysis revealed that the BsmI (B)-ApaI (A)-TaqI (t) participants compared with BsmI (b)-ApaI (a)-TaqI (T) individuals were less likely to have high Gleason scores (odds ratio, 0.84; 95% confidence interval, 0.71-1.00; P(unadjusted) = 0.050; P(adjusted) = 0.014). Our finding provides some support for the hypothesis that low levels of vitamin D may increase the risk of prostate cancer progression.

Associations of lower urinary tract symptoms with prostate-specific antigen levels, and screen-detected localized and advanced prostate cancer: a case-control study nested within the UK population-based ProtecT (Prostate testing for cancer and Treatment) study.

OBJECTIVE: To determine associations of lower urinary tract symptoms (LUTS) with prostate-specific antigen (PSA) levels and screen-detected localized and advanced prostate cancer. SUBJECTS AND METHODS: A case-control study nested within the UK population-based ProtecT (Prostate testing for cancer and Treatment) study. Men aged 50-69 years were invited for PSA testing and those with a PSA level of >or=3.0 ng/mL were invited for biopsy. We determined whether LUTS were associated with a PSA level of >or=3.0 ng/mL and prostate cancer using logistic regression models adjusted for age, family history of prostate cancer and PSA level as appropriate. Areas under receiver operating characteristic curves (AUC) were compared between models with and without symptoms. RESULTS: In all, 65 871 men had a PSA test: 7251 had a PSA level of >or=3.0 ng/mL including 2467 subsequently diagnosed with prostate cancer (2119 localized, 348 advanced). LUTS were positively associated with a PSA level of >or=3.0 ng/mL: odds ratios (ORs) were 1.18 (95% confidence interval, CI 1.01-1.38), 1.69 (95% CI 1.32-2.16), and 1.60 (95% CI 1.33-1.93) for daytime urination frequency (hourly vs less frequent), urgency and hesitancy (most/all the time vs never), respectively. LUTS among men with a PSA level of >or=3 ng/mL were negatively associated with prostate cancer: ORs were 0.44 (95% CI 0.22-0.83), 0.74 (95% CI 0.63-0.87), and 0.83 (95% CI 0.73-0.94) for nocturia (4+ vs 0), leakage and hesitancy (occasionally/sometimes vs never), respectively. LUTS improved the prediction of a PSA level of >or=3.0 ng/mL (AUC 0.635 vs 0.606, P < 0.001) and prostate cancer (AUC 0.661 vs 0.638; P < 0.001). CONCLUSIONS: A history of LUTS before PSA testing marginally improves the prediction of an individual's risk for prostate cancer; men with a PSA level of >or=3 ng/mL and LUTS were more likely to be diagnosed with benign disease than prostate cancer.

Bone morphogenetic protein 6 in skeletal metastases from prostate cancer and other common human malignancies.

Prostatic adenocarcinoma commonly metastasizes to bone. Unlike most other bony secondaries, the majority of skeletal prostatic metastases are osteoblastic rather than osteolytic in nature. Several growth factors which are known to stimulate bone formation are expressed in benign and malignant prostate cells, but none has been specifically linked to osteosclerotic metastases. Bone morphogenetic proteins (BMPs) induce ectopic bone formation in vivo. We have reported previously that BMP-6 mRNA and protein are expressed in the majority of primary prostatic carcinomas with established skeletal metastases but rarely in clinically organ-confined tumours. This study examines the expression of BMP-6 mRNA in matched prostatic primary and secondary bony lesions and in isolated skeletal metastases from prostatic adenocarcinomas, as well as other common human malignancies, by in situ hybridization. BMP-6 mRNA was detected in 11 out of 13 bone metastases from prostate carcinoma and in three paired samples of primary prostate carcinoma and matching skeletal metastasis. Weak signals for BMP-6 were also present in 5 out of 17 skeletal deposits from non-prostatic malignancies. BMP-6 mRNA appears to be strongly expressed in prostatic adenocarcinomas, both in the primary tumour and in bone metastases. It is also expressed, though less frequently, in skeletal metastases from other human carcinomas. Our findings suggest that BMP-6 may hold potential as an attractive marker and possible mediator of skeletal metastases, particularly in prostate carcinoma.

Rapid microwave-stimulated fixation of entire prostatectomy specimens. Biomed-II MPC Study Group.

Conventional fixation of large solid surgical specimens is a slow process. Consequently, autolytic damage to tissues may occur if the fixative does not reach the central part of the specimen in time. However, as there is also a time relationship between formalin fixation and antigen masking, fixation for too long can also be detrimental. In seeking the optimum balance for fixation, microwave irradiation might be of assistance. This study set out to evaluate methods for fixing entire prostate glands within a brief period of time, using microwave-stimulated formalin fixation. The results show that entire prostates can be optimally fixed if formalin is present throughout the tissue as the temperature is increased by microwave irradiation. This is achieved by injecting the fixative into the prostate at multiple sites immediately following prostatectomy. The technique described ensures standardization of a critical step during tissue processing, leading to uniform microscopic results with both routine and immunohistochemical stains. It is a simple, rapid method, suitable for routine diagnostic use. Using this modified approach, DNA of much larger sizes can be extracted from paraffin-embedded material, which could expand the possibilities for molecular analysis.

A meta-analysis of 87,040 individuals identifies 23 new susceptibility loci for prostate cancer.

Genome-wide association studies (GWAS) have identified 76 variants associated with prostate cancer risk predominantly in populations of European ancestry. To identify additional susceptibility loci for this common cancer, we conducted a meta-analysis of > 10 million SNPs in 43,303 prostate cancer cases and 43,737 controls from studies in populations of European, African, Japanese and Latino ancestry. Twenty-three new susceptibility loci were identified at association P < 5 × 10(-8); 15 variants were identified among men of European ancestry, 7 were identified in multi-ancestry analyses and 1 was associated with early-onset prostate cancer. These 23 variants, in combination with known prostate cancer risk variants, explain 33% of the familial risk for this disease in European-ancestry populations. These findings provide new regions for investigation into the pathogenesis of prostate cancer and demonstrate the usefulness of combining ancestrally diverse populations to discover risk loci for disease.

Adherence to dietary and lifestyle recommendations and prostate cancer risk in the prostate testing for cancer and treatment (ProtecT) trial.

BACKGROUND: The World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR) published eight recommendations for cancer prevention, but they are not targeted at prostate cancer prevention. We investigated whether adherence to the WCRF/AICR recommendations and a prostate cancer dietary index is associated with prostate cancer risk. METHODS: We conducted a nested case-control study of 1,806 prostate-specific antigen (PSA)-detected prostate cancer cases and 12,005 controls in the ProtecT trial. We developed a prostate cancer dietary index by incorporating three dietary factors most strongly associated with prostate cancer. Scores were computed to quantify adherence to the WCRF/AICR recommendations and the prostate cancer dietary index separately. RESULTS: The prostate cancer dietary index score was associated with decreased risk of prostate cancer [OR per 1 score increment: 0.91; 95% confidence interval (CI): 0.84-0.99; Ptrend = 0.04] but the WCRF/AICR index score was not (OR: 0.99; 95% CI: 0.94-1.05; Ptrend = 0.71). There was no heterogeneity in association by prostate cancer stage (P = 0.81) or grade (P = 0.61). Greater adherence to recommendations to increase plant foods (OR per 0.25 index score increment: 0.94; 95% CI: 0.89-0.99; Ptrend = 0.02) and tomato products (OR adherence vs. nonadherence: 0.82; 95% CI: 0.70-0.97; P = 0.02) was inversely associated with overall prostate cancer risk. CONCLUSIONS: Adherence to the prostate cancer-specific dietary recommendations was associated with decreased risk of prostate cancer. High intake of plant foods and tomato products in particular may help protect against prostate cancer. IMPACT: Meeting the WCRF/AICR recommendations alone is insufficient for prostate cancer prevention. Additional dietary recommendations should be developed.

bcl-2 overexpression combined with p53 protein accumulation correlates with hormone-refractory prostate cancer.

Seventy-seven men with histologically proven and newly diagnosed prostate cancer we investigated for the presence of bcl-2 protein overexpression and p53 protein accumulation 1 immunohistochemistry. Forty-five men had evidence of locally advanced and metastatic disease and we treated by means of hormone manipulation. Twenty-eight patients either failed to respond to initial hormone manipulation or relapsed within 37 months from diagnosis (median 20 months). Of the 77 cancers, 37 (48% showed bcl-2 overexpression at diagnosis. Twenty-seven of those were treated with androgen ablation and 2 (74%) had hormone-refractory disease (P = 0.0128). Twenty-three of 77 men (29.8%) had nuclear staining for p53 protein. Twenty-one of those were treated with hormone manipulation and 14 (66.6%) showed hormone resistance (P = 0.0012). Seventeen patients had both bcl-2 overexpression and p53 protein accumulation, 16 of whom were hormonally treated, with 13 (81.2%) having hormone-refractory disease (P < 0.0001). These findings suggest that the combined detection of p53 protein accumulation and bcl-2 overexpression may be useful in predicting hormone resistance in prostate cancer. By deregulating programmed cell death, alteration in these genes may prevent patients from responding to androgen ablation, or allow them to escape hormonal control of the disease.

Prediction of individual genetic risk to prostate cancer using a polygenic score.

BACKGROUND: Polygenic risk scores comprising established susceptibility variants have shown to be informative classifiers for several complex diseases including prostate cancer. For prostate cancer it is unknown if inclusion of genetic markers that have so far not been associated with prostate cancer risk at a genome-wide significant level will improve disease prediction. METHODS: We built polygenic risk scores in a large training set comprising over 25,000 individuals. Initially 65 established prostate cancer susceptibility variants were selected. After LD pruning additional variants were prioritized based on their association with prostate cancer. Six-fold cross validation was performed to assess genetic risk scores and optimize the number of additional variants to be included. The final model was evaluated in an independent study population including 1,370 cases and 1,239 controls. RESULTS: The polygenic risk score with 65 established susceptibility variants provided an area under the curve (AUC) of 0.67. Adding an additional 68 novel variants significantly increased the AUC to 0.68 (P = 0.0012) and the net reclassification index with 0.21 (P = 8.5E-08). All novel variants were located in genomic regions established as associated with prostate cancer risk. CONCLUSIONS: Inclusion of additional genetic variants from established prostate cancer susceptibility regions improves disease prediction.

Physical activity, alcohol consumption, BMI and smoking status before and after prostate cancer diagnosis in the ProtecT trial: opportunities for lifestyle modification.

Associations between certain lifestyle characteristics and prostate cancer risk have been reported, and continuation post-diagnosis can adversely affect prognosis. We explored whether men make spontaneous changes to their physical activity and alcohol intake, body mass index (BMI) and smoking status, following a diagnosis of localised prostate cancer. A detailed diet, health and lifestyle questionnaire was completed by 511 participants within the Prostate Testing for Cancer and Treatment (ProtecT) randomised controlled trial, both before and 9 months after a diagnosis of prostate cancer. Of 177 men who were insufficiently active before their diagnosis (median 0 activity units/week; IQR 0-9), 40.7% had increased their activity by a median of 22 U week(-1) (IQR 15-35) 9 months later, and there was weak evidence that men were more active after diagnosis than before (p = 0.07). Men categorised as "working" occupational social class and who were insufficiently active before diagnosis were 2.03 (95%, CI = 1.03-3.99, p = 0.04) times more likely to have increased their physical activity levels compared to men classified as "managerial or professional." Similarly, men who were insufficiently active pre-diagnosis and with T-stage 2 compared with T-stage 1 prostate cancer were 2.47 (95%, CI = 1.29-4.71, p = 0.006) times more likely to be sufficiently active post-diagnosis. Following diagnosis, there was an overall reduction in alcohol intake (p = 0.03) and the proportion of current smokers (p = 0.09), but no overall change in BMI. We conclude that some men spontaneously change certain lifestyle behaviours on receiving a diagnosis of prostate cancer. For many men, however, additional support through lifestyle interventions is probably required to facilitate and maintain these changes.

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.

Height and prostate cancer risk: a large nested case-control study (ProtecT) and meta-analysis.

BACKGROUND: Height, a marker of childhood environmental exposures, is positively associated with prostate cancer risk, perhaps through the insulin-like growth factor system. We investigated the relationship of prostate cancer with height and its components (leg and trunk length) in a nested case-control study and with height in a dose-response meta-analysis. METHODS: We nested a case-control study within a population-based randomized controlled trial evaluating treatments for localized prostate cancer in British men ages 50 to 69 years, including 1,357 cases detected through prostate-specific antigen testing and 7,990 controls (matched on age, general practice, assessment date). Nine bibliographic databases were searched systematically for studies on the height-prostate cancer association that were pooled in a meta-analysis. RESULTS: Based on the nested case-control, the odds ratio (OR) of prostate-specific antigen-detected prostate cancer per 10 cm increase in height was 1.06 [95% confidence interval (95% CI): 0.97-1.16; p(trend) = 0.2]. There was stronger evidence of an association of height with high-grade prostate cancer (OR: 1.23; 95% CI: 1.06-1.43), mainly due to the leg component, but not with low-grade disease (OR: 0.99; 95% CI: 0.90-1.10). In general, associations with leg or trunk length were similar. A meta-analysis of 58 studies found evidence that height is positively associated with prostate cancer (random-effects OR per 10 cm: 1.06; 95% CI: 1.03-1.09), with a stronger effect for prospective studies of more advanced/aggressive cancers (random-effects OR: 1.12; 95% CI: 1.05-1.19). CONCLUSION: These data indicate a limited role for childhood environmental exposures-as indexed by adult height-on prostate cancer incidence, while suggesting a greater role for progression, through mechanisms requiring further investigation.