Search results

Characteristics of men responding to an invitation to undergo testing for prostate cancer as part of a randomised trial.

BACKGROUND: Sociodemographic characteristics are associated with participating in cancer screening and trials. We compared the characteristics of those responding with those not responding to a single invitation for prostate-specific antigen (PSA) testing for prostate cancer as part of the Cluster randomised triAl of PSA testing for Prostate cancer (CAP). METHODS: Age, rurality and deprivation among 197,763 men from 271 cluster-randomised primary care centres in the UK were compared between those responding (n = 90,300) and those not responding (n = 100,953) to a prostate cancer testing invitation. RESULTS: There was little difference in age between responders and nonresponders. Responders were slightly more likely to come from urban rather than rural areas and were slightly less deprived than those who did not respond. CONCLUSION: These data indicate similarities in age and only minor differences in deprivation and urban location between responders and nonresponders. These differences were smaller, but in the same direction as those observed in other screening trials. TRIAL REGISTRATION: ISRCTN92187251 . Registered on 29 November 2004.

In Defense of Randomized Clinical Trials in Surgery: Let Us Not Forget Archie Cochrane's Legacy.

Alcohol consumption and prostate cancer incidence and progression: A Mendelian randomisation study.

Prostate cancer is the most common cancer in men in developed countries, and is a target for risk reduction strategies. The effects of alcohol consumption on prostate cancer incidence and survival remain unclear, potentially due to methodological limitations of observational studies. In this study, we investigated the associations of genetic variants in alcohol-metabolising genes with prostate cancer incidence and survival. We analysed data from 23,868 men with prostate cancer and 23,051 controls from 25 studies within the international PRACTICAL Consortium. Study-specific associations of 68 single nucleotide polymorphisms (SNPs) in 8 alcohol-metabolising genes (Alcohol Dehydrogenases (ADHs) and Aldehyde Dehydrogenases (ALDHs)) with prostate cancer diagnosis and prostate cancer-specific mortality, by grade, were assessed using logistic and Cox regression models, respectively. The data across the 25 studies were meta-analysed using fixed-effect and random-effects models. We found little evidence that variants in alcohol metabolising genes were associated with prostate cancer diagnosis. Four variants in two genes exceeded the multiple testing threshold for associations with prostate cancer mortality in fixed-effect meta-analyses. SNPs within ALDH1A2 associated with prostate cancer mortality were rs1441817 (fixed effects hazard ratio, HRfixed  = 0.78; 95% confidence interval (95%CI):0.66,0.91; p values = 0.002); rs12910509, HRfixed  = 0.76; 95%CI:0.64,0.91; p values = 0.003); and rs8041922 (HRfixed  = 0.76; 95%CI:0.64,0.91; p values = 0.002). These SNPs were in linkage disequilibrium with each other. In ALDH1B1, rs10973794 (HRfixed  = 1.43; 95%CI:1.14,1.79; p values = 0.002) was associated with prostate cancer mortality in men with low-grade prostate cancer. These results suggest that alcohol consumption is unlikely to affect prostate cancer incidence, but it may influence disease progression.

Mutational signatures of ionizing radiation in second malignancies.

Ionizing radiation is a potent carcinogen, inducing cancer through DNA damage. The signatures of mutations arising in human tissues following in vivo exposure to ionizing radiation have not been documented. Here, we searched for signatures of ionizing radiation in 12 radiation-associated second malignancies of different tumour types. Two signatures of somatic mutation characterize ionizing radiation exposure irrespective of tumour type. Compared with 319 radiation-naive tumours, radiation-associated tumours carry a median extra 201 deletions genome-wide, sized 1-100 base pairs often with microhomology at the junction. Unlike deletions of radiation-naive tumours, these show no variation in density across the genome or correlation with sequence context, replication timing or chromatin structure. Furthermore, we observe a significant increase in balanced inversions in radiation-associated tumours. Both small deletions and inversions generate driver mutations. Thus, ionizing radiation generates distinctive mutational signatures that explain its carcinogenic potential.

Novel biomarkers for the detection of prostate cancer.

Prostate-specific antigen (PSA) is widely used as a biomarker in the detection of prostate cancer and for decision making regarding treatment options, response to therapy, and clinical follow-up. Despite its widespread use, it is well recognised that PSA has suboptimal performance as a screening tool due to poor specificity, resulting in high negative biopsy rates and potential 'over-diagnosis' and 'over-treatment' of clinically insignificant cancers. In particular, PSA does not reliably distinguish either cancer from benign prostatic conditions, or 'clinically significant' from 'indolent cancers', and it is inaccurate in predicting disease burden and response to treatment. There is an urgent demand for novel biomarkers to address these clinical needs. This article provides an update on the novel candidate biomarkers in development, which have shown potential for improving the detection of clinically significant cases of this malignancy.

Understanding and Improving Recruitment to Randomised Controlled Trials: Qualitative Research Approaches.

CONTEXT: The importance of evidence from randomised trials is now widely recognised, although recruitment is often difficult. Qualitative research has shown promise in identifying the key barriers to recruitment, and interventions have been developed to reduce organisational difficulties and support clinicians undertaking recruitment. OBJECTIVE: This article provides an introduction to qualitative research techniques and explains how this approach can be used to understand-and subsequently improve-recruitment and informed consent within a range of clinical trials. EVIDENCE ACQUISITION: A literature search was performed using Medline, Embase, and CINAHL. All studies with qualitative research methods that focused on the recruitment activity of clinicians were included in the review. EVIDENCE SYNTHESIS: The majority of studies reported that organisational difficulties and lack of time for clinical staff were key barriers to recruitment. However, a synthesis of qualitative studies highlighted the intellectual and emotional challenges that arise when combining research with clinical roles, particularly in relation to equipoise and patient eligibility. To support recruiters to become more comfortable with the design and principles of randomised controlled trials, interventions have been developed, including the QuinteT Recruitment Intervention, which comprises in-depth investigation of recruitment obstacles in real time, followed by implementation of tailored strategies to address these challenges as the trial proceeds. CONCLUSIONS: Qualitative research can provide important insights into the complexities of recruitment to trials and inform the development of interventions, and provide support and training initiatives as required. Investigators should consider implementing such methods in trials expected to be challenging or recruiting below target. PATIENT SUMMARY: Qualitative research is a term used to describe a range of methods that can be implemented to understand participants' perspectives and behaviours. Data are gathered from interviews, focus groups, or observations. In this review, we demonstrate how this approach can be used to understand-and improve-recruitment to clinical trials. Taken together, our review suggests that healthcare professionals can find recruiting to trials challenging and require support with this process.

Post-diagnosis serum insulin-like growth factors in relation to dietary and lifestyle changes in the Prostate testing for cancer and Treatment (ProtecT) trial.

PURPOSE: The insulin-like growth factor (IGF) system is modifiable by diet and lifestyle, and has been linked to prostate cancer development and progression. METHODS: We conducted a prospective cohort study of 621 men diagnosed with localized prostate cancer to investigate the associations of dietary and lifestyle changes with post-diagnosis circulating levels of IGF-I and IGFBP-3. We used analysis of covariance to estimate the associations, controlling for baseline IGF-I or IGFBP-3, respectively. RESULTS: Mean IGF-I levels were 6.5% (95% CI -12.8, -0.3%, p = 0.04) lower in men who decreased their protein intake after diagnosis compared to men who did not change. Men who changed their fruit and vegetable intake had lower IGF-I levels compared to non-changers [Decreased intake: -10.1%, 95% CI -18.4, -1.8%, p = 0.02; Increased intake: -12.0%, 95% CI -18.4, -1.8%, p = 0.002]. IGFBP-3 was 14.6% (95% CI -24.5, -4.8%, p = 0.004) lower in men who achieved a healthy body mass index after diagnosis. Men who became inactive had 9.5% higher average IGF-I levels (95% CI 0.1, 18.9%, p = 0.05). CONCLUSIONS: Decreased protein intake and body mass index, and increased physical activity and fruit and vegetable intake, following a prostate cancer diagnosis were associated with reduced post-diagnosis serum IGF-I and IGFBP-3. Counterintuitively, reduced fruit and vegetable intake was also associated with reduced IGF-I, but with weak statistical support, possibly implicating chance. If confirmed in other studies, our findings may inform potential lifestyle interventions in prostate cancer. ProtecT was registered at International Standard Randomised Controlled Trial Registry, http://isrctn.org as ISRCTN20141297.

Height, selected genetic markers and prostate cancer risk: results from the PRACTICAL consortium.

BACKGROUND: Evidence on height and prostate cancer risk is mixed, however, recent studies with large data sets support a possible role for its association with the risk of aggressive prostate cancer. METHODS: We analysed data from the PRACTICAL consortium consisting of 6207 prostate cancer cases and 6016 controls and a subset of high grade cases (2480 cases). We explored height, polymorphisms in genes related to growth processes as main effects and their possible interactions. RESULTS: The results suggest that height is associated with high-grade prostate cancer risk. Men with height >180 cm are at a 22% increased risk as compared to men with height <173 cm (OR 1.22, 95% CI 1.01-1.48). Genetic variants in the growth pathway gene showed an association with prostate cancer risk. The aggregate scores of the selected variants identified a significantly increased risk of overall prostate cancer and high-grade prostate cancer by 13% and 15%, respectively, in the highest score group as compared to lowest score group. CONCLUSIONS: There was no evidence of gene-environment interaction between height and the selected candidate SNPs.Our findings suggest a role of height in high-grade prostate cancer. The effect of genetic variants in the genes related to growth is seen in all cases and high-grade prostate cancer. There is no interaction between these two exposures.

10-Year Outcomes in Localized Prostate Cancer.

Investigating the genetic relationship between Alzheimer's disease and cancer using GWAS summary statistics.

Growing evidence from both epidemiology and basic science suggest an inverse association between Alzheimer's disease (AD) and cancer. We examined the genetic relationship between AD and various cancer types using GWAS summary statistics from the IGAP and GAME-ON consortia. Sample size ranged from 9931 to 54,162; SNPs were imputed to the 1000 Genomes European panel. Our results based on cross-trait LD Score regression showed a significant positive genetic correlation between AD and five cancers combined (colon, breast, prostate, ovarian, lung; r g = 0.17, P = 0.04), and specifically with breast cancer (ER-negative and overall; r g = 0.21 and 0.18, P = 0.035 and 0.034) and lung cancer (adenocarcinoma, squamous cell carcinoma and overall; r g = 0.31, 0.38 and 0.30, P = 0.029, 0.016, and 0.006). Estimating the genetic correlation in specific functional categories revealed mixed positive and negative signals, notably stronger at annotations associated with increased enhancer activity. This suggests a role of gene expression regulators in the shared genetic etiology between AD and cancer, and that some shared variants modulate disease risk concordantly while others have effects in opposite directions. Due to power issues, we did not detect cross-phenotype associations at individual SNPs. This genetic overlap is not likely driven by a handful of major loci. Our study is the first to examine the co-heritability of AD and cancer leveraging large-scale GWAS results. The functional categories highlighted in this study need further investigation to illustrate the details of the genetic sharing and to bridge between different levels of associations.

Systematic Review of Studies Reporting Positive Surgical Margins After Bladder Neck Sparing Radical Prostatectomy.

PURPOSE OF REVIEW: Bladder neck preservation (BNP) during radical prostatectomy (RP) has been proposed as a method to improve early recovery of urinary continence after radical prostatectomy. However, there is concern over a possible increase in the risk of positive surgical margins and prostate cancer recurrence rate. A recent systematic review and meta-analysis reported improved early recovery and overall long-term urinary continence without compromising oncologic control. The aim of our study was to perform a critical review of the literature to assess the impact on bladder neck and base margins after bladder neck sparing radical prostatectomy. EVIDENCE ACQUISITION: We carried out a systematic review of the literature using Pubmed, Scopus and Cochrane library databases in May 2017 using medical subject headings and free-text protocol according to PRISMA guidelines. We used the following search terms: bladder neck preservation, prostate cancer, radical prostatectomy and surgical margins. Studies focusing on positive surgical margins (PSM) in bladder neck sparing RP pertinent to the objective of this review were included. EVIDENCE SYNTHESIS: Overall, we found 15 relevant studies reporting overall and site-specific positive surgical margins rate after bladder neck sparing radical prostatectomy. This included two RCTs, seven prospective comparative studies, two retrospective comparative studies and four case series. All studies were published between 1993 and 2015 with sample sizes ranging between 50 and 1067. Surgical approaches included open, laparoscopic and robot-assisted radical prostatectomy. The overall and base-specific PSM rates ranged between 7-36% and 0-16.3%, respectively. Mean base PSM was 4.9% in those patients where bladder neck sparing was performed, but only 1.85% in those without sparing. Bladder neck preservation during radical prostatectomy may increase base-positive margins. Further studies are needed to better investigate the impact of this technique on oncological outcomes. A future paradigm could include modification of intended approach to bladder neck dissection when anterior base lesions are identified on pre-operative MRI.

Diagnostic Pathways for Screen-detected Prostate Cancer: The Plot Thickens.

Reducing Mortality in the Ageing Patient: Treatment of the Primary Tumour Is Not Necessary.

Robot-assisted radical prostatectomy for older men remains an unproven intervention in terms of both cancer control and functional and voiding outcomes. We highlight some of the evidence against radical surgery for older men while acknowledging that this is the direction of travel.

Orient Expression: Solving the Mystery of Asian Prostate Cancer?

Survival Among Men at High Risk of Disseminated Prostate Cancer Receiving Initial Locally Directed Radical Treatment or Initial Androgen Deprivation Therapy.

BACKGROUND: There is increasing low-quality evidence rationalizing the use of radical therapy for men at high risk of disseminated prostate cancer. OBJECTIVE: To investigate, using high-quality epidemiologic data, whether initial radical therapy in men at high risk of disseminated prostate cancer improves survival. DESIGN, SETTING, AND PARTICIPANTS: An observational population-based Swedish study from 1996 to 2010 of men at high risk of disseminated prostate cancer (prostate-specific antigen [PSA] >50) initially treated by radical therapy (radiation therapy [n=630] or radical prostatectomy [n=120]) or androgen deprivation therapy (n=17 602), and followed for up to 15 yr. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Prostate-cancer and other-cause mortality was estimated for the treatment groups. We also matched the two cohorts for grade, T stage, M stage, Charlson score, year of diagnosis, age, and PSA, and found androgen deprivation therapy patient matches for 575 of the radical therapy patients, and then repeated comparative effectiveness analyses. RESULTS AND LIMITATION: Prostate-cancer mortality was substantially greater in the androgen deprivation therapy group compared with the radically treated one, in unmatched (9062/17 602 vs 86/750) and matched (177/575 vs 71/575) cohorts. Among matched cohorts, initial androgen deprivation therapy was associated with nearly three-fold higher hazard of prostate-cancer death compared with initial radical therapy (2.87; 95% confidence interval 2.16-3.82). Multiple sensitivity analyses suggested that the findings were robust, although the general limitations of nonrandomized studies remain. Further, the study cohort may have included men with both systemic and nonsystemic disease, as a sole eligibility criterion of PSA >50 was used. CONCLUSIONS: This large and comprehensive population-based study suggests that initial radical therapy in men at high risk of disseminated prostate cancer improves survival. PATIENT SUMMARY: This large Swedish study suggests that men with prostate cancer that has spread beyond the prostate benefit from treating the prostate itself with radiation therapy or surgery rather than treating the disease with hormones alone.

Estimating age and ethnic variation in the histological prevalence of prostate cancer to inform the impact of screening policies.

OBJECTIVES: To estimate histological prevalence of prostate cancer by age and ethnic group. METHODS: A literature review identified autopsy studies of men without clinical diagnosis of prostate cancer during their lifetime. A total of 25 studies fulfilled the inclusion criteria, and a Bayesian logistic meta-regression was carried out to examine the association between histological prevalence, age by decade and ethnic group (white, African American and Chinese/Japanese). RESULTS: Histological cancer was estimated to increase with age from 2% (95% confidence interval 1-3%) between 20-29 years-of-age to 69% (95% confidence interval 51-83%) by 90-99 years-of-age in the white ethnic group. The African American group was associated with the highest prevalence of cancer, albeit non-significantly (odds ratio 1.2, 95% confidence interval 0.9-1.5), whereas the Chinese/Japanese group was significantly associated with the lowest prevalence relative to the white group (odds ratio 0.6, 95% confidence interval 0.4-0.9). CONCLUSIONS: The present study provides an updated and improved analysis of the histological prevalence of prostate cancer. The results confirm ethnicity as a potential predictor of prevalence, but highlight the need for further research in the area. The findings are valuable for understanding the epidemiology and natural history of prostate cancer across ethnicities, and increasing the body of evidence aimed at estimating benefits and risks associated with prostate cancer screening programs.

Value of Intact Prostate Specific Antigen and Human Kallikrein 2 in the 4 Kallikrein Predictive Model: An Individual Patient Data Meta-Analysis.

PURPOSE: The 4 kallikrein panel, commercially available as the 4Kscore®, is a statistical model that has been shown to accurately predict Gleason Grade Group 2 or greater (high grade) cancer on biopsy and the long-term risk of distant prostate cancer metastases. The panel includes 2 novel markers, namely intact prostate specific antigen and hK2. It has been questioned whether these 2 additional markers add discrimination to the clinical predictors of patient age, digital rectal examination and prior biopsy, and the established molecular markers total and free prostate specific antigen. MATERIALS AND METHODS: We performed an individual patient data meta-analysis of published studies in which the 4 kallikrein panel was measured in men undergoing prostate biopsy. We assess the improvement in discrimination associated with including intact prostate specific antigen and hK2 along with total and free prostate specific antigen in the statistical model. RESULTS: Included in analysis were 14,510 men from a total of 10 studies. The fixed effects meta-analytical estimate of the discrimination of the model without intact prostate specific antigen and hK2 was 0.742 (95% CI 0.727-0.756) compared to 0.813 (95% CI 0.801-0.825) for the full kallikrein model. The 95% CIs did not overlap and the difference in discrimination was highly statistically significant (0.069, 95% CI 0.057-0.080, p <0.0001). Intact prostate specific antigen (increase in discrimination 0.059, 95% CI 0.050-0.069) and hK2 (increase in discrimination 0.024, 95% CI 0.020-0.029, each p <0.0001) added independently to the model. CONCLUSIONS: The clinical value of the panel could not be replicated using data readily available to urologists without measuring intact prostate specific antigen and hK2.

Properties of the 4-Kallikrein Panel Outside the Diagnostic Gray Zone: Meta-Analysis of Patients with Positive Digital Rectal Examination or Prostate Specific Antigen 10 ng/ml and Above.

PURPOSE: The 4-kallikrein panel, commercially available as the 4Kscore™, is a reflex test for prostate cancer early detection that has been extensively validated in multiple international cohorts. It has been suggested that use of such reflex tests be limited to those with prostate specific antigen less than 10 ng/ml and negative digital rectal examination. We aimed to determine the value of the panel in men outside this "diagnostic gray zone." MATERIALS AND METHODS: We performed an individual patient data meta-analysis using data from prior studies on the 4-kallikrein panel. We calculated the properties of the panel for predicting high grade (Gleason 7+) cancer in a subgroup of men with either positive digital rectal examination or prostate specific antigen 10 to 25 ng/ml. RESULTS: A total 2,891 men from 8 cohorts were included. An important proportion of patients, including 32% in the United States validation study, had prostate specific antigen 10 to 25 ng/ml or a positive digital rectal examination. For men with prostate specific antigen 10 to 25 ng/ml the fixed-effects estimate for the discrimination of the kallikrein model was 0.84 vs 0.69 for the base model (difference 0.128, 95% CI 0.098-0.159). In the positive digital rectal examination group discrimination was 0.82 vs 0.72 (difference 0.092, 95% CI 0.069-0.115). Decision analysis showed a clinical net benefit for use of the panel in this subgroup with a reduction in biopsy rates of about 20% and only a small number of high grade cancers missed, or fewer than 3% of those not biopsied. CONCLUSIONS: The use of the kallikrein panel in men with a positive digital rectal examination or prostate specific antigen 10 to 25 ng/ml is justified.

Estimating the sensitivity of a prostate cancer screening programme for different PSA cut-off levels: A UK case study.

INTRODUCTION: Policy decisions about prostate cancer screening require data on the natural history of histological cancers and the resulting impact of screening. However, the gold standard procedure required to identify true positive histological cancer is a full autopsy of the gland which is not possible in screening studies, leading to verification bias. We aim to estimate the sensitivity of a prostate cancer screening round (PSA result to diagnosis) relative to histological cancer. METHODS: We developed a framework combining data on UK screened and non-screened prostate cancer populations originating from a single round of population-based PSA testing among UK men aged 50-69 years, prostate cancer incidence data, and needle biopsy data from the published literature. RESULTS: Sensitivity of a screening round was highest at age 65-69 years at 33% (95% CI: 30%-37%) and 24% (95% CI: 21%-28%) for PSA cut-off levels of 3 ng/ml and 4 ng/ml, respectively. Sensitivity was lowest at age 50-54 at 15% (95% CI: 12%-17%) and 9% (95% CI: 8%-11%) for PSA cut-off levels of 3 ng/ml and 4 ng/ml, respectively. In contrast, the clinical detection rate in the absence of mass screening, relative to histological cancer, varied between 0.2%-0.7% at age 50-54 and 1.2%-2.7% at age 65-69 from 1995 to 2012. CONCLUSIONS: The framework enabled the sensitivity of a prostate cancer screening round relative to histological cancer diagnosis to be estimated and provides a basis to determine the impact and cost-effectiveness of prostate cancer screening. The approach could be adapted to inform the sensitivity of other biomarkers, cancers and screening programmes.

Supporting prostate cancer survivors in primary care: Findings from a pilot trial of a nurse-led psycho-educational intervention (PROSPECTIV).

PURPOSE: This study sought to test the acceptability and feasibility of a nurse-led psycho-educational intervention (NLPI) delivered in primary care to prostate cancer survivors, and to provide preliminary estimates of the effectiveness of the intervention. METHODS: Men who reported an ongoing problem with urinary, bowel, sexual or hormone-related functioning/vitality on a self-completion questionnaire were invited to participate. Participants were randomly assigned to the NLPI plus usual care, or to usual care alone. Recruitment and retention rates were assessed. Prostate-related quality of life, self-efficacy, unmet needs, and psychological morbidity were measured at baseline and 9 months. Health-care resource use data was also collected. An integrated qualitative study assessed experiences of the intervention. RESULTS: 61% eligible men (83/136) participated in the trial, with an 87% (72/83) completion rate. Interviews indicated that the intervention filled an important gap in care following treatment completion, helping men to self-manage, and improving their sense of well-being. However, only a small reduction in unmet needs and small improvement in self-efficacy was observed, and no difference in prostate-related quality of life or psychological morbidity. Patients receiving the NLPI recorded more primary care visits, while the usual care group recorded more secondary care visits. Most men (70%; (21/30)) felt the optimal time for the intervention was around the time of diagnosis/before the end of treatment. CONCLUSIONS: Findings suggest a nurse-led psycho-educational intervention in primary care is feasible, acceptable and potentially useful to prostate cancer survivors.