Prostate Cancer Risk Research Articles

Fish consumption and risk of prostate cancer or its mortality: an updated systematic review and dose-response meta-analysis of prospective cohort studies.

Since the release of the last meta-analysis on the association between fish intake and prostate cancer risk, several cohort studies have been published. Moreover, none of the previous meta-analyzes examined the dose-response association between fish intake and prostate cancer. Therefore, the current dose-response meta-analysis was conducted to summarize available findings on the associations of fish intake with the risk of prostate cancer in men. Online databases of PubMed, Scopus, and Web of Science were systematically searched up to September 2022. We included prospective cohort studies that examined the associations of fish intake with the risk of prostate cancer (total, localized, and advanced prostate cancer), its mortality, and cancer progression. Summary relative risks (RR) and 95% confidence intervals (CI) were calculated for the highest versus lowest categories of fish intake using random-effects models. Also, linear and non-linear dose-response analyzes were conducted. In total, 25 prospective cohort studies, recruiting 1,216,474 men, were included in the systematic review, and 22 studies were included in the meta-analysis. During the follow-up periods, ranging from 6 to 33 years, a total of 44,722 cases of prostate cancer were recorded. The comparison between the highest and lowest intakes of total fish revealed the summary RRs of 0.97 (95% CI: 0.86-1.10) for total, 1.01 (95% CI: 0.91-1.13) for advanced, and 0.90 (95% CI: 0.72-1.12) for localized prostate cancer, indicating no significant association. Moreover, the summary RR was 0.55 (95% CI: 0.33-0.92) for prostate cancer mortality and 0.84 (95% CI: 0.65-1.10) for prostate cancer progression, indicating an inverse association between fish intake and prostate cancer mortality. Also, in the dose-response analyzes, each 20 gram/day increase in total fish intake was associated with a 12% lower risk of prostate cancer mortality. Our findings support the protective association between total fish intake and the risk of prostate cancer mortality.

VPAC targeted optical imaging assay (VPAC assay) of voided urine for management of patients with persistently elevated PSA.

124 Background: Nearly 50% of patients with persistently elevated PSA (PEP) have prostate cancer (PCa) despite previous negative biopsy. However not all patients agree to undergo repeat, invasive trans rectal or trans perineal prostate biopsy (PB). To identify men at high risk of PCa, the need is unmet of other reliable diagnostic methods. The goal of this investigation was to determine if the VPAC assay, which is being developed in our laboratory and detects PCa efficiently, by imaging PCa cells shed in voided urine, collected without digital rectal examination (DRE), can address the common clinical dilemma of when or if to repeat biopsy on PEP subjects. Methods: PEP patients (N=21, 55-75 yr. PSA 2.8 – 42 ng/ml), scheduled for PB and signed informed consent form were enrolled. They provided pre and clinically required, post DRE urine. VPAC assay was performed on both urine samples from each patient. VPAC, a genomic receptor, encodes G protein and expresses in high density on all malignant PCa cells, was targeted with TP4303, a biomolecule with fluorophore, designed in our laboratory with high affinity (Kd, 3.1x10-9M) for VPAC. Urine was centrifuged, cells on a glass slide fixed, incubated with TP4303 and excess was washed. Cells were then examined under a microscope. TP4303 fluorescence around cell nucleus allowed to identify malignant PCa cells. For urine collected post DRE, MDx Health assay, approved by FDA and determines mRNA levels of DXL1 and HOXC6 biomarkers and indicates risk of PCa, was also performed. Results were compared with gold standard histopathology of tissues acquired through PB, and evaluated statistically. Results: Of 21 PEP patients, who underwent PB, three (14%) had histopathologically proven, clinically significant PCa with Grade Group 2. All three (100%) patients were correctly identified as positive for PCa by the VPAC assay, while MDx reported low risk for two (9.5%) and high risk for one (53%). Of the remaining 18, histologically negative subjects, VPAC assay was disconcordant in five (28%), with positive for PCa. In these five patients, MDx also reported moderate to high risk (40%-59%). Of the remaining 13 histologically negative PCa patient, all (100%) had concordant results with VPAC assay while MDx reported low risk in 2 patients and moderate to high risk (range 30% to 90%) in other eleven. Results with sensitivity and specificity of the assays are given in the table. Conclusions: The VPAC assay data, in this small exploratory cohort, appear promising as an additional diagnostic in the clinical management of PEP patients, minimizing the number of unnecessary invasive PBs and eliminating possible overtreatment. Work is in progress. Support: NIH 5R01CA249921. [Table: see text]

Reply: Prostate Cancer and Cardiovascular Risk Factors.

Reply: Prostate Cancer and Cardiovascular Risk Factors.

Awareness of prostate cancer and its associated factors among male patients attending care in the urology unit at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia

BackgroundGlobally, prostate cancer is the most common cancer among men. It is the second most common cause of cancer-related deaths in men. Symptoms may be non-specific and may not present...

ELAC2 is a functional prostate cancer risk allele.

Stentenbach and colleagues have unveiled a functional role of a human germline mutation found in the ribonuclease (RNase) Z enzyme, ELAC2, in prostate cancer. Here, we discuss the importance of these findings in enhancing our understanding of how risk variants enable prostate cancer progression and the post-transcriptional mechanisms underlying oncogenesis.

Combined CRISPRi and proteomics screening reveal a cohesin-CTCF-bound allele contributing to increased expression of RUVBL1 and prostate cancer progression

Genome-wide association studies along with expression quantitative trait locus (eQTL) mapping have identified hundreds of single-nucleotide polymorphisms (SNPs) and their target genes in prostate cancer (PCa), yet functional characterization of these risk loci remains challenging. To screen for potential regulatory SNPs, we designed a CRISPRi library containing 9,133 guide RNAs (gRNAs) to cover 2,166 candidate SNP loci implicated in PCa and identified 117 SNPs that could regulate 90 genes for PCa cell growth advantage. Among these, rs60464856 was covered by multiple gRNAs significantly depleted in screening (FDR<0.05). Pooled SNP association analysis in the PRACTICAL and FinnGen cohorts showed significantly higher PCa risk for the rs60464856G allele (p value= 1.2×10-16 and 3.2×10-7, respectively). Subsequent eQTL analysis revealed that the G allele is associated with increased RUVBL1 expression in multiple datasets. Further CRISPRi and xCas9 base editing confirmed that the rs60464856G allele leads to elevated RUVBL1 expression. Furthermore, SILAC-based proteomic analysis demonstrated allelic binding of cohesin subunits at the rs60464856 region, where the HiC dataset showed consistent chromatin interactions in prostate cell lines. RUVBL1 depletion inhibited PCa cell proliferation and tumor growth in a xenograft mouse model. Gene-set enrichment analysis suggested an association of RUVBL1 expression with cell-cycle-related pathways. Increased expression of RUVBL1 and activation of cell-cycle pathways were correlated with poor PCa survival in TCGA datasets. Our CRISPRi screening prioritized about one hundred regulatory SNPs essential for prostate cell proliferation. In combination with proteomics and functional studies, we characterized the mechanistic role of rs60464856 and RUVBL1 in PCa progression.

Initial Postoperative Prostate Specific Antigen and Prostate Specific Antigen Velocity Are Important Indicators of Underlying Malignancy After Simple Prostatectomy.

Background: There is a paucity of guidelines for prostate-specific antigen (PSA) monitoring after simple prostatectomy (SP) despite these patients remaining at risk for prostate cancer (PCa). Our objective was to determine if PSA kinetics can be a potential indicator of PCa after SP. Methods: A retrospective review was performed of all simple prostatectomies at our institution from 2014 to 2022. All patients who met criteria were included in the study. Relevant clinical variables were collected preoperatively, including PSA value, prostate size, and voiding symptoms. Surgical and urinary function outcomes were analyzed. Results: A total of 92 patients were divided into two groups based on malignancy status. Sixty-eight patients did not have PCa, while 24 patients had known PCa before surgery (14) or were diagnosed as having incidental PCa from the pathological specimen (10). Patients with benign prostates had an initial postoperative PSA value of 0.76 ng/mL compared with 1.68 ng/mL for those with cancer (p < 0.01). PSA velocity for the first 24 months after surgery was 0.042 ± 1.61 ng/(mL·year) for the benign cohort compared with 1.29 ± 1.02 ng/(mL·year) for the malignant cohort (p = 0.01). Voiding improvements were noted by objective (postvoid residual and flow rate) and subjective (American Urological Association symptom score and quality of life score) measures in both groups. Conclusions: PSA interpretation and monitoring after SP have not been well established. Our study indicates that initial postoperative PSA value and PSA velocity are important indicators of underlying malignancy in patients after SP. Further efforts are needed to establish threshold values and formal guidelines.

Clinical efficacy of prostate PI-RADS V2.1 score combined with serum PSA-related indicators in the detection of gray zone prostate cancer.

The purpose of this study is to improve the diagnostic accuracy of gray zone prostate cancer evaluation by combining the prostate imaging report and data system version 2.1 (PI-RADS V2.1) score with serum prostate-specific antigen (PSA). We analyzed data from 212 men suspected of having prostate cancer and compared PSA-related indicators and PI-RADS V2.1 scores between 96 patients with prostate cancer and 116 without prostate cancer. By contrasting PI-RADS V2.1 scores with serum PSA-related markers, the diagnostic precision in the detection of grey zone prostate cancer was assessed. The median PI-RADS V2.1 scores and serum tPSA levels of patients with prostate cancer were significantly higher (P < 0.05). The PI-RADS V2.1 score correlated positively with serum tPSA, PSA density (PSAD), and prostate health index (PHI) levels (P < 0.05) and negatively correlated with fPSA/tPSA concentrations (P < 0.05). Logistic regression identified risk factors including family history, PI-RADS V2.1 score, tPSA, PSAD, and PHI, with prostate volume and fPSA/tPSA as protective factors (P < 0.05). Combining serum PSA-related indicators with the PI-RADS V2.1 score improved diagnostic accuracy for gray zone prostate cancer (AUC 0.986, specificity 99.14%, sensitivity 92.71%). The presence of a family history, a high PI-RADS V2.1 score, and elevated serum PSA-related markers contribute to high prostate cancer risk and development. The combined use of these indicators offers superior predictive value in detecting prostate cancer compared to a single indicator.

Determination of Prostate Specific Antigen Level among Male Patients with Bacterial Urinary Tract Infections Attending Kuje General Hospital Abuja, Nigeria

Recent hospital and cancer registry data shows increasing prostate cancer incidence in Nigeria, which was previously regarded as a low incidence region. Prostate cancer is the leading cause of cancer death among men in Nigeria and second most common cancers of men worldwide and sexual history has been a consistent risk factor. Prostate specific antigen (PSA) test is still the single most important test for early detection of prostate cancer worldwide. However, not much is reported about prostate cancer in relation to urinary tract infections in Africa. This study investigates the prevalence of prostate cancer risk in and bacterial urinary tract infections among men in Abuja, Nigeria. One Hundred (100) samples each of blood and urine were collected, from fifty (50) male patients suffering from urinary tract infections and fifty (50) apparently healthy males attending Kuje General Hospital Abuja, Nigeria. All the blood samples were subjected to PSA analysis using Enzyme-linked Immunosorbent Assay procedure (Diagnostic Automation/ Cortez Diagnostics, Inc, USA) while urine analysis (microscopy, culture and biochemical identification) was performed on the urine to isolate and identify the common bacteria associated with urinary tract infections among the study population.

A Splicing Transcriptome-Wide Association Study Identifies Candidate Altered Splicing for Prostate Cancer Risk.

Prostate cancer (PCa) represents a huge public health burden among men. Many susceptibility genetic factors for PCa still remain unknown. In this study, we performed a large splicing transcriptome-wide association study (spTWAS) using three modeling strategies to develop alternative splicing genetic prediction models for identifying novel susceptibility loci and splicing introns for PCa risk by assessing 79,194 cases and 61,112 controls of European ancestry in the PRACTICAL, CRUK, CAPS, BPC3, and PEGASUS consortia. We identified 120 splicing introns of 97 genes showing an association with PCa risk at false discovery rate (FDR)-corrected threshold (FDR <0.05). Of them, 33 genes were enriched in PCa-related diseases and function categories. Fine-mapping analysis suggested that 21 splicing introns of 19 genes were likely causally associated with PCa risk. Thirty-five splicing introns of 34 novel genes were identified to be related to PCa susceptibility for the first time, and 11 of the genes were enriched in a cancer-related network. Our study identified novel loci and splicing introns associated with PCa risk, which can improve our understanding of the etiology of this common malignancy.

Rosiglitazone has a null association with the risk of prostate cancer in type 2 diabetes patients.

This study investigated the risk of prostate cancer in ever users and never users of rosiglitazone in diabetes patients in Taiwan. The nationwide database of the National Health Insurance was used to enroll male patients who had a new diagnosis of type 2 diabetes mellitus at an age ≥ 25 years from 1999 to 2005.A total of 11,495 ever users and 11,495 never users of rosiglitazone matched on propensity score were selected and they were followed up for the incidence of prostate cancer from January 1, 2006 until December 31, 2011. Cox proportional hazard model incorporated with the inverse probability of treatment weighting using the propensity score was used to estimate hazard ratios. At the end of follow-up, incident cases of prostate cancer were found in 84 never users and 90 ever users of rosiglitazone. The calculated incidence was 173.20 per 100,000 person-years in never users and was 187.59 per 100,000 person-years in ever users. The overall hazard ratio (95% confidence intervals) for ever versus never users was 1.089 (0.808-1.466). The hazard ratios were 0.999 (0.643-1.552) for the first tertile (< 672 mg), 1.147 (0.770-1.709) for the second tertile (672-3584 mg) and 1.116 (0.735-1.695) for the third tertile (> 3584 mg) of cumulative dose. Sensitivity analyses consistently showed a null association between rosiglitazone and prostate cancer risk. Rosiglitazone has a null effect on the risk of prostate cancer.

The potential role of the microbiota in prostate cancer pathogenesis and treatment.

The human body hosts a complex and dynamic population of trillions of microorganisms - the microbiota - which influences the body in homeostasis and disease, including cancer. Several epidemiological studies have associated specific urinary and gut microbial species with increased risk of prostate cancer; however, causal mechanistic data remain elusive. Studies have associated bacterial generation of genotoxins with the occurrence of TMPRSS2-ERG gene fusions, a common, early oncogenic event during prostate carcinogenesis. A subsequent study demonstrated the role of the gut microbiota in prostate cancer endocrine resistance, which occurs, at least partially, through the generation of androgenic steroids fuelling oncogenic signalling via the androgen receptor. These studies present mechanistic evidence of how the host microbiota might be implicated in prostate carcinogenesis and tumour progression. Importantly, these findings also reveal potential avenues for the detection and treatment of prostate cancer through the profiling and modulation of the host microbiota. The latter could involve approaches such as the use of faecal microbiota transplantation,prebiotics, probiotics, postbiotics or antibiotics, which can be used independently or combined with existing treatments to reverse therapeutic resistance and improve clinical outcomes in patients with prostate cancer.

Atopic allergic conditions and prostate cancer risk and survival in the Multiethnic Cohort study

BackgroundPrevious studies investigating relationship between atopic allergic conditions (AACs)—a highly reactive immune state—and prostate cancer (PCa) risk were inconclusive, and few have studied diverse racial/ethnic populations.MethodsWe analysed 74,714 men aged ≥45 years at enrollment in Multiethnic Cohort study. Using multivariable Cox regression, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for self-reported AAC status on PCa outcomes.ResultsThrough 2017, 8697 incident PCa and 1170 related deaths occurred. Twenty-one percent of men reported a history of AACs. AACs were not associated with incident PCa (HR = 0.98, 95% CI: 0.93–1.03) but were significantly inversely associated with PCa mortality (HR = 0.79, 95% CI: 0.67–0.92). This inverse association was consistently observed across all racial/ethnic groups (HR range: 0.60–0.90). Among men diagnosed with PCa, AACs were inversely associated with PCa-specific death (HR = 0.75, 95% CI: 0.63–0.89). Adjusting for potential confounding effect of PSA screening did not meaningfully change the results. No significant heterogeneity was observed in the effect of AACs on PCa incidence or mortality by Dietary Inflammatory Index.ConclusionsHyper-allergic conditions were not associated with PCa incidence but were inversely associated with PCa mortality, suggesting a potential role in reducing tumour progression. Further aetiological research is warranted to understand underlying mechanisms.

Diabetes medications and cancer risk associations: a systematic review and meta-analysis of evidence over the past 10 years

Diabetes medications may modify the risk of certain cancers. We systematically searched MEDLINE, Embase, Web of Science, and Cochrane CENTRAL from 2011 to March 2021 for studies evaluating associations between diabetes medications and the risk of breast, lung, colorectal, prostate, liver, and pancreatic cancers. A total of 92 studies (3 randomized controlled trials, 64 cohort studies, and 25 case–control studies) were identified in the systematic review, involving 171 million participants. Inverse relationships with colorectal (n = 18; RR = 0.85; 95% CI = 0.78–0.92) and liver cancers (n = 10; RR = 0.55; 95% CI = 0.46–0.66) were observed in biguanide users. Thiazolidinediones were associated with lower risks of breast (n = 6; RR = 0.87; 95% CI = 0.80–0.95), lung (n = 6; RR = 0.77; 95% CI = 0.61–0.96) and liver (n = 8; RR = 0.83; 95% CI = 0.72–0.95) cancers. Insulins were negatively associated with breast (n = 15; RR = 0.90; 95% CI = 0.82–0.98) and prostate cancer risks (n = 7; RR = 0.74; 95% CI = 0.56–0.98). Positive associations were found between insulin secretagogues and pancreatic cancer (n = 5; RR = 1.26; 95% CI = 1.01–1.57), and between insulins and liver (n = 7; RR = 1.74; 95% CI = 1.08–2.80) and pancreatic cancers (n = 8; RR = 2.41; 95% CI = 1.08–5.36). Overall, biguanide and thiazolidinedione use carried no risk, or potentially lower risk of some cancers, while insulin secretagogue and insulin use were associated with increased pancreatic cancer risk.

Baseline renal function and the risk of cancer among apparently healthy middle-aged adults

BackgroundThe association between mildly impaired renal function with all-site and site-specific cancer risk is not established. We aim to explore this association among apparently healthy adults. MethodsWe followed 25,073 men and women, aged 40–79 years, free of cancer or cardiovascular disease at baseline who were screened annually in preventive healthcare settings. The estimated glomerular filtration rate (eGFR) was calculated using the CKD Epidemiology Collaboration equation (CKD-EPI) and classified into four mutually exclusive groups: <60, 60–74, 75–89, ≥90 (mL/min/1.73 m²). The primary outcome was all-site cancer while the secondary outcome was site-specific cancer. Cancer data was available from a national registry. ResultsMean age at baseline was 50 ± 8 years and 7973 (32 %) were women. During a median follow-up of 9 years (IQR 3–16) and 256,279 person years, 2045 (8.2 %) participants were diagnosed with cancer. Multivariable Cox model showed a 1.2 (95 %CI: 1.0–1.4 p = 0.05), 1.2 (95 %CI: 1.0–1.4 p = 0.02), and 1.4 (95 %CI: 1.1–1.7 p = 0.003) higher risk for cancer with eGFR of 75–89, 60–74, and < 60, respectively. Site-specific analysis demonstrated a 1.8 (95 %CI: 1.2–2.6 p = 0.004), 1.7 (95 %CI: 1.2–2.6 p = 0.004) and 2.2 (95 %CI: 1.3–3.6 p = 0.002) increased risk for prostate cancer with eGFR of 75–89, 60–74, and < 60, respectively. eGFR< 60 was associated with a 2.0 (95 %CI: 1.1–3.7 p = 0.03) and 3.7 (95 %CI: 1.1–13.1 p = 0.04) greater risk for melanoma and gynecological caner respectively. ConclusionsCKD stage 2 and worse is independently associated with higher risk for cancer incidence, primarily prostate cancer. Early intervention and screening are warranted among these individuals in order to reduce cancer burden.

Expression and clinical value of NLRP1 and NLRC4 inflammasomes in prostate cancer.

The present study explored the clinical value of the protein expression levels of nucleotide binding oligomerization-like receptor family pyrin domain containing 1 (NLRP1) and nucleotide-binding oligomerization domain leucine-rich repeat and caspase recruitment domain-containing 4 (NLRC4) inflammasomes in the diagnosis and treatment of prostate cancer. A total of 54 patients with prostatic hyperplasia and 58 patients with prostate cancer were recruited at The First People's Hospital of Pinghu between January and May 2022. Immunohistochemical staining was used to determine the protein expression levels of the NLRP1 and NLRC4 inflammasomes in addition to the proinflammatory cytokines IL-18 and IL-1β in the two groups of patients. The protein expression levels of NLRP1 and NLRC4 inflammasome were significantly increased in patients with prostate cancer compared with patients with prostate hyperplasia. The differences in expression of NLRP1 and NLRC4 inflammatory vesicles in prostate cancer of different stages were also compared based on data from The Cancer Genome Atlas. The protein expression level of NLRP1 demonstrated a significant positive correlation with IL-1β and IL-18 expression, and the protein expression level of the NLRC4 inflammasome was significantly positively correlated with IL-18 expression. The protein expression levels of both NLRP1 and NLRC4 demonstrated a significant positive correlation with the Gleason score of prostate cancer. The expression of NLRP1 in tumor (T)3/T4 was significantly higher compared with T1 and expression of the NLRC4 inflammasome in T2 and T3/T4 was significantly higher compared with T1. Expression of the NLRP1 and NLRC4 inflammasomes was significantly higher in patients with prostate cancer, compared with patients with prostatic hyperplasia. Therefore, expression of NLRP1 and NLRC4 may promote tumorigenesis by promoting the maturation and release of proinflammatory cytokines IL-1β and IL-18. Expression of the NLRP1 and NLRC4 inflammasomes demonstrated a significant positive correlation with the risk of prostate cancer. Expression of the NLRP1 and NLRC4 inflammasomes in middle- and advanced-stage tumors was higher compared with early-stage tumors. These results suggested that inflammasome expression may serve a significant role in the progression of tumors and could provide a fixed value for the risk assessment and prognosis prediction of prostate cancer.

The Effect of Racial Concordance on Patient Trust in Online Videos About Prostate Cancer

Black men have a higher risk of prostate cancer compared with White men, but Black adults are underrepresented in online content about prostate cancer. Across racial groups, the internet is a popular source of health information; Black adults are more likely to trust online health information, yet have more medical mistrust than White adults. To evaluate the association between racial representation in online content about prostate cancer and trust in the content and identify factors that influence trust. A randomized clinical trial was conducted from August 18, 2021, to January 7, 2022, consisting of a 1-time online survey. Participants included US men and women aged 40 years and older. Data were analyzed from January 2022 to June 2023. Participants were randomized to watch the same video script about either prostate cancer screening or clinical trials presented by 1 of 4 speakers: a Black physician, a Black patient, a White physician, or a White patient, followed by a questionnaire. The primary outcome was a published scale for trust in the information. χ2 tests and multivariable logistic regression were used to compare trust according to the video's speaker and topic. Among 2904 participants, 1801 (62%) were men, and the median (IQR) age was 59 (47-69) years. Among 1703 Black adults, a greater proportion had high trust in videos with Black speakers vs White speakers (72.7% vs 64.3%; adjusted odds ratio [aOR], 1.62; 95% CI, 1.28-2.05; P < .001); less trust with patient vs physician presenter (64.6% vs 72.5%; aOR, 0.63; 95% CI, 0.49-0.80; P < .001) and about clinical trials vs screening (66.3% vs 70.7%; aOR, 0.78; 95% CI, 0.62-0.99; P = .04). Among White adults, a lower proportion had high trust in videos featuring a patient vs physician (72.0% vs 78.6%; aOR, 0.71; 95% CI, 0.54-0.95; P = .02) and clinical trials vs screening (71.4% vs 79.1%; aOR, 0.57; 95% CI, 0.42-0.76; P < .001), but no difference for Black vs White presenters (76.8% vs 73.7%; aOR, 1.11; 95% CI, 0.83-1.48; P = .49). In this randomized clinical trial, prostate cancer information was considered more trustworthy when delivered by a physician, but racial concordance was significantly associated with trust only among Black adults. These results highlight the importance of physician participation and increasing racial diversity in public dissemination of health information and an ongoing need for public education about clinical trials. ClinicalTrials.gov Identifier: NCT05886751.

The Prediagnosis of Prostate Cancer Risk is Possible with the Evaluation of BRCA1 Primary Exons in Men

The Prediagnosis of Prostate Cancer Risk is Possible with the Evaluation of BRCA1 Primary Exons in Men

Fictitious cases as a methodology to discuss sensitive health topics in focus groups

ABSTRACT Purpose It can be challenging to research aspects of people’s health behaviour, attitudes, and emotions due to the sensitive nature of these topics. We aimed to develop a novel methodology for discussing sensitive health topics, and explore the effectiveness in focus groups using prostate cancer and screening as an example. Method We developed a fictitious case and employed it as a projective technique in focus groups on prostate cancer and screening. The participants were men and their partners who lived in Denmark. Results The technique encouraged emotional and cognitive openness in focus group discussions about the risk of prostate cancer, the benefits and harms of screening, and decision-making about screening. It appeared that using the fictitious case allowed the participants to personally distance themselves from the topic, project emotions onto the case, and thereby openly talk about their emotions. Conclusion This article presents a methodological contribution to communication about sensitive topics in focus groups, using prostate cancer screening as an example. Further refinement of the methodology is needed to enable participants to transfer improvements in knowledge to their own decision about screening.

Association between Outdoor Light at Night and Prostate Cancer in the Health Professionals Follow-up Study.

Circadian disruption is a potential risk factor for advanced prostate cancer, and light at night (LAN) exposure may disrupt circadian rhythms. We evaluated whether outdoor LAN increases the risk of prostate cancer. We prospectively followed 49,148 participants in the Health Professionals Follow-up Study from 1986 through 2016. We estimated baseline and cumulative time-varying outdoor LAN with ∼1 km2 resolution using data from the US Defense Meteorological Satellite Program's Operational Linescan System, which was assigned to participants' geocoded addresses. Participants reside in all 50 U.S. states and reported a work or home address. We used multivariable Cox models to estimate HRs and 95% confidence intervals (CI) for the association between outdoor LAN and risk of overall (7,175 cases) and fatal (915 cases) prostate cancer adjusting for individual and contextual factors. There was no association between the interquartile range increase in cumulative LAN and total (HR, 1.02; 95% CI, 0.98-1.06) or fatal (HR, 1.05; 95% CI, 0.96-1.15) prostate cancer in adjusted models. However, there was a positive association between baseline LAN and total prostate cancer among non-movers (HR, 1.06; 95% CI, 1.00-1.14) including among highly screened participants (HR, 1.11; 95% CI, 1.01-1.23). There was a suggestive positive association between baseline outdoor LAN and total prostate cancer. Additional studies with different measures of outdoor LAN and in more diverse populations are necessary. To our knowledge, this is the first longitudinal cohort study exploring the relationship between outdoor LAN and prostate cancer.