Joint associations between established genetic susceptibility loci, pesticide exposures, and risk of prostate cancer.

More than 200 genetic variants have been independently associated with prostate cancer risk. Studies among farmers have also observed increased prostate cancer risk associated with exposure to specific organophosphate (fonofos, terbufos, malathion, dimethoate) and organochlorine (aldrin, chlordane) insecticides. We examined the joint associations between these pesticides, established prostate cancer loci, and prostate cancer risk among 1,162 cases (588 aggressive) and 2,206 frequency-matched controls nested in the Agricultural Health Study cohort. History of lifetime pesticide use was combined with a polygenic risk score (PRS) generated using 256 established prostate cancer risk variants. Logistic regression models estimated the joint associations of the pesticides, the PRS, and the 256 individual genetic variants with risk of total and aggressive prostate cancer. Likelihood ratio tests assessed multiplicative interaction. We observed interaction between ever use of fonofos and the PRS in relation to total and aggressive prostate cancer risk. Compared to the reference group (never use, PRS < median), men with ever use of fonofos and PRS > median had elevated risks of total (OR 1.35 [1.06-1.73], p-interaction = 0.03) and aggressive (OR 1.49 [1.09-2.04], p-interaction = 0.19) prostate cancer. There was also suggestion of interaction between pesticides and individual genetic variants occurring in regions associated with DNA damage response (CDH3, EMSY genes) and with variants related to altered androgen receptor-driven transcriptional programs critical for prostate cancer. Our study provides evidence that men with greater genetic susceptibility to prostate cancer may be at higher risk if they are also exposed to pesticides and suggests potential mechanisms by which pesticides may increase prostate cancer risk.

Circulating free testosterone and risk of aggressive prostate cancer: Prospective and Mendelian randomisation analyses in international consortia.

Previous studies had limited power to assess the associations of testosterone with aggressive disease as a primary endpoint. Further, the association of genetically predicted testosterone with aggressive disease is not known. We investigated the associations of calculated free and measured total testosterone and sex hormone-binding globulin (SHBG) with aggressive, overall and early-onset prostate cancer. In blood-based analyses, odds ratios (OR) and 95% confidence intervals (CI) for prostate cancer were estimated using conditional logistic regression from prospective analysis of biomarker concentrations in the Endogenous Hormones, Nutritional Biomarkers and Prostate Cancer Collaborative Group (up to 25 studies, 14 944 cases and 36 752 controls, including 1870 aggressive prostate cancers). In Mendelian randomisation (MR) analyses, using instruments identified using UK Biobank (up to 194 453 men) and outcome data from PRACTICAL (up to 79 148 cases and 61 106 controls, including 15 167 aggressive cancers), ORs were estimated using the inverse-variance weighted method. Free testosterone was associated with aggressive disease in MR analyses (OR per 1 SD = 1.23, 95% CI = 1.08-1.40). In blood-based analyses there was no association with aggressive disease overall, but there was heterogeneity by age at blood collection (OR for men aged <60 years 1.14, CI = 1.02-1.28; Phet  = .0003: inverse association for older ages). Associations for free testosterone were positive for overall prostate cancer (MR: 1.20, 1.08-1.34; blood-based: 1.03, 1.01-1.05) and early-onset prostate cancer (MR: 1.37, 1.09-1.73; blood-based: 1.08, 0.98-1.19). SHBG and total testosterone were inversely associated with overall prostate cancer in blood-based analyses, with null associations in MR analysis. Our results support free testosterone, rather than total testosterone, in the development of prostate cancer, including aggressive subgroups.

Associations between daily aspirin use and cancer risk across strata of major cancer risk factors in two large U.S. cohorts.

PURPOSE: Daily aspirin use has been shown to reduce risk of colorectal, and possibly other, cancers, but it is unknown if these benefits are consistent across subgroups of people with differing cancer risk factors. We investigated whether age, body mass index (BMI), smoking status, physical inactivity, and family history of cancer modify the effect of daily aspirin use on colorectal, ovarian, breast, endometrial and aggressive prostate cancer risk. METHODS: We pooled 423,495 individuals from two prospective, U.S.-based studies: the NIH-AARP Diet and Health Study (1995-2011) and the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (1993-2009). Using Cox proportional hazards regression, we examined associations between daily aspirin use (≥ 5 days/week) and risk of colorectal, ovarian, breast, endometrial, and aggressive prostate cancer, overall and across strata of risk factors. RESULTS: Daily aspirin use was associated with a 15% reduction in colorectal cancer risk (hazard ratio [HR]: 0.85, 95% confidence interval [CI] 0.80-0.89). Risk reductions were generally consistent across strata of risk factors but attenuated with increasing BMI (p-interaction = 0.16). For ovarian cancer, there was no significant association overall (HR: 0.93, 95% CI 0.80-1.08) but reduced risk among obese women (HR: 0.73, 95% CI 0.52-0.98, p-interaction = 0.12). Weak or null associations were observed for breast, endometrial, and aggressive prostate cancer, with no strong effect modification observed. CONCLUSIONS: Daily aspirin use appears to reduce colorectal cancer risk regardless of other risk factors, though the potential modifying effect of BMI warrants further investigation and may need to be considered in risk-benefit calculations for aspirin use.

Overall and abdominal obesity and prostate cancer risk in a West African population: An analysis of the Ghana Prostate Study.

Obesity has been associated with an increased risk of advanced prostate cancer. However, most studies have been conducted among North American and European populations. Prostate cancer mortality appears elevated in West Africa, yet risk factors for prostate cancer in this region are unknown. We thus examined the relationship between obesity and prostate cancer using a case-control study conducted in Accra, Ghana in 2004 to 2012. Cases and controls were drawn from a population-based sample of 1037 men screened for prostate cancer, yielding 73 cases and 964 controls. An additional 493 incident cases were recruited from the Korle-Bu Teaching Hospital. Anthropometric measurements were taken at enrollment. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR) and prostate cancer, adjusting for potential confounders. The mean BMI was 25.1 kg/m2 for cases and 24.3 kg/m2 for controls. After adjustment, men with BMI ≥ 30 kg/m2 had an increased risk of prostate cancer relative to men with BMI < 25 kg/m2 (OR 1.86, 95% CI 1.11-3.13). Elevated WC (OR 1.76, 95% CI 1.24-2.51) and WHR (OR 1.46, 95% CI 0.99-2.16) were also associated with prostate cancer. Associations were not modified by smoking status and were evident for low- and high-grade disease. These findings indicate that overall and abdominal obesity are positively associated with prostate cancer among men in Ghana, implicating obesity as a potentially modifiable risk factor for prostate cancer in this region.

Aspirin use and ovarian cancer risk using extended follow-up of the PLCO Cancer Screening Trial.

OBJECTIVE: Frequent use of aspirin has been associated with reduced ovarian cancer risk in observational studies, but it is unclear if only daily, low-dose aspirin confers a protective benefit. We examined associations between patterns of aspirin use and ovarian cancer risk among postmenopausal women in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. METHODS: Participants were enrolled in PLCO between 1993 and 2001 and followed for cancer outcomes through 2014. Detailed data on aspirin use (e.g., dose, frequency and duration) were ascertained via the supplemental questionnaire (SQX) administered in 2006-2007. We used Cox proportional hazards regression to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between aspirin use (defined as use ≥once/week) and incident ovarian cancer. We conducted analyses among all women in the study sample and stratified by age at the time of the SQX. RESULTS: There were 41,633 women included in this analysis, of whom 223 developed incident ovarian cancer. Overall, aspirin use was not significantly associated with ovarian cancer risk (HR: 0.93, 95% CI: 0.72-1.21). Among women <70 years, there was suggestion of an inverse association for daily use of aspirin (HR: 0.65, 95% CI: 0.40-1.05), low-dose aspirin (HR: 0.79, 95% CI: 0.51-1.24) and daily use of low-dose aspirin (HR: 0.64, 95% CI: 0.38-1.09). CONCLUSIONS: These findings suggest a potential modest effect of daily, low-dose aspirin in reducing ovarian cancer risk. However, effect estimates were imprecise given the small number of events, and further research will be needed to confirm and extend these findings.

Impact of Subsequent Biopsies on Comprehensive Health Related Quality of Life in Patients with and without Prostate Cancer.

PURPOSE: The aim of this study was to identify the effects of subsequent prostate needle biopsies after the baseline biopsy on health related quality of life with time. We compared men with and without prostate cancer, and men who did and did not undergo followup prostate needle biopsy. MATERIALS AND METHODS: Included in analysis were patients enrolled in the Center for Prostate Disease Research Multicenter National Database between 2007 and 2015 who had low or favorable intermediate risk prostate cancer, were on active surveillance and underwent prostate needle biopsy for suspicion of prostate cancer. Patients completed the EPIC (Expanded Prostate Cancer Index Composite) and the RAND SF-36 (36-Item Short Form Health Survey) after baseline biopsy and at regular followup intervals. Mean health related quality of life was compared with time between patients who did and did not undergo subsequent prostate needle biopsies following baseline. RESULTS: Of the 637 patients included in study 129 (20.3%) with prostate cancer were on active surveillance and 508 (79.7%) were in the noncancer group. In the cancer and noncancer groups mean ± SD followup was 34.7 ± 16.9 and 31.6 ± 14.6 months, respectively. Of the patients with prostate cancer 54 (60.7%) underwent subsequent prostate needle biopsies compared with 114 (27.1%) without cancer. No significant impact on health related quality of life was observed in men who underwent subsequent prostate needle biopsies during a 5-year period. CONCLUSIONS: A subsequent prostate needle biopsy is required in most active surveillance protocols and in men with persistent suspicion of prostate cancer. Our analysis shows that subsequent prostate needle biopsies do not significantly impact health related quality of life.

A prospective study of health-related quality of life outcomes among men treated for intermediate- and high-risk prostate cancer: the impact of primary and secondary therapies.

INTRODUCTION: To assess the impact of primary and secondary therapies for high- and intermediate-risk prostate cancer on health-related quality of life (HRQoL). MATERIALS AND METHODS: A prospective study was initiated in 2007 at Center for Prostate Disease Research Multicenter National Database sites. Longitudinal patterns in HRQoL from baseline (pre-treatment) to 5 years post-diagnosis were examined for patients with high- and intermediate-risk prostate cancer, treated by radical prostatectomy (RP) or external beam radiation therapy (EBRT). Change in HRQoL was modeled using linear regression models fit with generalized estimating equations. The probability of maintaining HRQoL was compared between patients receiving RP only versus RP with secondary treatment. RESULTS: Of 445 men with high- and intermediate-risk prostate cancer, 228 underwent RP and 143 had EBRT± androgen deprivation therapy (ADT). Fifty received secondary therapy (EBRT and/or ADT or chemotherapy) after RP. RP patients showed a greater decline over time in sexual function and bother and urinary function compared to EBRT±ADT patients. Patients who had secondary therapy after RP were less likely to maintain their HRQoL compared to those who had RP alone. These differences were most pronounced for sexual and hormonal function. CONCLUSIONS: Prostate cancer patients experience significant declines in HRQoL after primary therapy. Additional secondary therapy after RP, in the form of EBRT and/or ADT, appears to be responsible for further deterioration in HRQoL outcomes.

Longitudinal regret after treatment for low- and intermediate-risk prostate cancer.

BACKGROUND: Prostate cancer patients diagnosed with low- and intermediate-risk disease have several treatment options. Decisional regret after treatment is a concern, especially when poor oncologic outcomes or declines in health-related quality of life (HRQoL) occur. This study assessed determinants of longitudinal decisional regret in prostate cancer patients attending a multidisciplinary clinic and treated with radical prostatectomy (RP), external beam radiation therapy (EBRT), brachytherapy (BT), or active surveillance (AS). METHODS: Patients newly diagnosed with prostate cancer at the Walter Reed National Military Medical Center who attended a multidisciplinary clinic were enrolled into a prospective study from 2006 to 2014. The Decision Regret Scale was administered at 6, 12, 24, and 36 months posttreatment. HRQoL was also assessed at regular intervals using the Expanded Prostate Cancer Index Composite and 36-item RAND Medical Outcomes Study Short Form questionnaires. Adjusted probabilities of reporting regret were estimated via multivariable logistic regression fitted with generalized estimating equations. RESULTS: A total of 652 patients met the inclusion criteria (395 RP, 141 EBRT, 41 BT, 75 AS). Decisional regret was consistently low after all of these treatments. In multivariable models, only African American race (odds ratio, 1.67; 95% confidence interval, 1.12-2.47) was associated with greater regret across time. Age and control preference were marginally associated with regret. Regret scores were similar between RP patients who did and did not experience biochemical recurrence. Declines in HRQoL were weakly correlated with greater decisional regret. CONCLUSION: In the context of a multidisciplinary clinic, decisional regret did not differ significantly between treatment groups but was greater in African Americans and those reporting poorer HRQoL. Cancer 2017;123:4252-4258. © 2017 American Cancer Society.

Prospective Quality of Life in Men Choosing Active Surveillance Compared to Those Biopsied but not Diagnosed with Prostate Cancer.

PURPOSE: Active surveillance is an important alternative to definitive therapy for men with low risk prostate cancer. However, the impact of active surveillance on health related quality of life compared to that in men without cancer remains unknown. In this study we evaluated health related quality of life outcomes in men on active surveillance compared to men followed after negative prostate needle biopsy. MATERIALS AND METHODS: A prospective study was conducted on men who were enrolled into the Center for Prostate Disease Research Multicenter National Database and underwent prostate needle biopsy for suspicion of prostate cancer between 2007 and 2014. Health related quality of life was assessed at biopsy (baseline) and annually for up to 3 years using SF-36 and EPIC questionnaires. Health related quality of life scores were modeled using generalized estimating equations, adjusting for baseline health related quality of life, and demographic and clinical characteristics. RESULTS: Of the 1,204 men who met the initial eligibility criteria 420 had a negative prostate needle biopsy (noncancer comparison group). Among the 411 men diagnosed with low risk prostate cancer 89 were on active surveillance. Longitudinal analysis revealed that for most health related quality of life subscales there were no significant differences between the groups in adjusted health related quality of life score trends over time. CONCLUSIONS: In this study most health related quality of life outcomes in patients with low risk prostate cancer on active surveillance did not differ significantly from those of men without prostate cancer. A comparison group of men with a similar risk of prostate cancer detection is critical to clarify the psychological and physical impact of active surveillance.

Prospective quality-of-life outcomes for low-risk prostate cancer: Active surveillance versus radical prostatectomy.

BACKGROUND: For patients with low-risk prostate cancer (PCa), active surveillance (AS) may produce oncologic outcomes comparable to those achieved with radical prostatectomy (RP). Health-related quality-of-life (HRQoL) outcomes are important to consider, yet few studies have examined HRQoL among patients with PCa who were managed with AS. In this study, the authors compared longitudinal HRQoL in a prospective, racially diverse, and contemporary cohort of patients who underwent RP or AS for low-risk PCa. METHODS: Beginning in 2007, HRQoL data from validated questionnaires (the Expanded Prostate Cancer Index Composite and the 36-item RAND Medical Outcomes Study short-form survey) were collected by the Center for Prostate Disease Research in a multicenter national database. Patients aged ≤75 years who were diagnosed with low-risk PCa and elected RP or AS for initial disease management were followed for 3 years. Mean scores were estimated using generalized estimating equations adjusting for baseline HRQoL, demographic characteristics, and clinical patient characteristics. RESULTS: Of the patients with low-risk PCa, 228 underwent RP, and 77 underwent AS. Multivariable analysis revealed that patients in the RP group had significantly worse sexual function, sexual bother, and urinary function at all time points compared with patients in the AS group. Differences in mental health between groups were below the threshold for clinical significance at 1 year. CONCLUSIONS: In this study, no differences in mental health outcomes were observed, but urinary and sexual HRQoL were worse for patients who underwent RP compared with those who underwent AS for up to 3 years. These data offer support for the management of low-risk PCa with AS as a means for postponing the morbidity associated with RP without concomitant declines in mental health.

Telomere length as a risk factor for hereditary prostate cancer.

BACKGROUND: Telomeres are repetitive nucleotide sequences that stabilize the ends of chromosomes. Critically short telomeres are thought to contribute to cancer development by increasing chromosomal instability. We hypothesized that shorter leukocyte telomere length, a surrogate for inherited prostate cell telomere length, would be associated with increased risk of prostate cancer in hereditary prostate cancer (HPC) families. METHODS: One hundred twelve affected and 63 unaffected men from 28 families were drawn from the Johns Hopkins HPC family database. Relative mean telomere length was measured in isolated peripheral leukocyte DNA by quantitative PCR. Conditional logistic regression was used to estimate the association between quartile of age-adjusted telomere length and prostate cancer. RESULTS: Men in the shortest quartile of telomere length did not have increased odds of prostate cancer compared to men in the other three quartiles (OR = 0.84, 95% CI: 0.32-2.20, P = 0.73). However, when the analysis was restricted to affected men with blood drawn before or within a year of diagnosis (N = 39) and all unaffected men, shorter telomere length was moderately associated with increased odds of prostate cancer (OR = 3.55, 95% CI: 0.82-15.43, P = 0.09). CONCLUSIONS: Though we found no association overall, shorter leukocyte telomere length may be associated with increased odds of prostate cancer when measured in pre-diagnostic samples. Further prospective research is warranted exploring the utility of telomere length as a prostate cancer biomarker.

An Updated Evaluation of Atrazine-Cancer Incidence Associations among Pesticide Applicators in the Agricultural Health Study Cohort.

BACKGROUND: Atrazine is a common agricultural herbicide in the United States. Few epidemiologic studies have evaluated cancer risks. Previous analyses within the Agricultural Health Study (AHS) have found some evidence of associations with cancer at some sites. OBJECTIVE: We updated exposure information, incident cases, and follow-up time to assess the associations between atrazine use and cancer at specific sites in the AHS. METHODS: Information about lifetime pesticide use was reported at enrollment (1993-1997) and follow-up (1999-2005). Among 53,562 pesticide applicators in North Carolina and Iowa, we identified 8,915 incident cases through cancer registry linkages through 2014 (North Carolina)/2017 (Iowa). We used Poisson regression to evaluate the association between ever/never and intensity-weighted lifetime days of atrazine use and incident cancer risk controlling for several confounders. We also evaluated lagged exposures and age-stratified risk. RESULTS: Approximately 71.2% of applicators reported ever using atrazine, which was associated with lung cancer [rate ratios (RR)=1.24; 95% confidence interval (CI): 1.04, 1.46]. Aggressive prostate cancer risk was increased in the highest quartile (RRQ4=1.20; 95% CI: 0.95, 1.52; p-trend=0.19), particularly among those <60 years old (RRQ4=3.04; 95% CI: 1.61, 5.75; p-trend<0.001; p-interaction=0.04). Among applicators <50 years of age, ever-atrazine use was associated with non-Hodgkin lymphoma (NHL) (RR=2.43; 95% CI: 1.10, 5.38; p-interaction=0.60). For soft tissue sarcoma, there was an elevated risk in the highest tertile of exposure (RRT3: 2.54; 95% CI: 0.97, 6.62; p-trend=0.31). In analyses with exposure lagged by 25 years, there was an elevated risk of pharyngeal (RRT3=3.04; 95% CI: 1.45, 6.36; p-trend=0.07) and kidney (RRQ4=1.62; 95% CI: 1.15, 2.29; p-trend<0.005) cancers. DISCUSSION: We observed suggestive associations with some malignancies in overall, age-specific, and lagged analyses. Associations with aggressive prostate cancer and NHL were apparent among those diagnosed at younger ages and with cancers of the pharynx and kidney, and soft tissue sarcomas were observed in lagged analyses. Further work is needed to confirm these observed associations and elucidate potential underlying mechanisms. https://doi.org/10.1289/EHP13684.

Obesity and prostate cancer screening, incidence, and mortality in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial.

BACKGROUND: Though obesity, measured by body mass index (BMI), is an established risk factor for several cancer sites, there is conflicting evidence on whether obesity increases prostate cancer risk or mortality and, if it does, whether it increases risk directly or indirectly by affecting prostate cancer screening efficacy. METHODS: We examined associations between BMI and prostate cancer screening outcomes, incidence, and mortality in men randomly assigned to the intervention arm of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (n = 36 756) between 1993 and 2001. Participants received annual screening with the prostate-specific antigen test and digital rectal exam. Associations between baseline BMI and screening outcomes were assessed via multinomial logistic regression, and associations with prostate cancer incidence and mortality were assessed via Cox proportional hazards regression. RESULTS: Individuals with higher BMI were less likely to screen positive via the prostate-specific antigen test and/or digital rectal exam and more likely to have an inadequate screen (all Ptrend < .01). Higher BMI was inversely associated with prostate cancer incidence (per 5 kg/m2 BMI increase: hazard ratio [HR] = 0.94, 95% confidence interval [CI] = 0.91 to 0.97), including incidence of early stage (HR = 0.94, 95% CI = 0.90 to 0.97) and advanced-stage (HR = 0.91, 95% CI = 0.82 to 1.02) disease, but positively associated with prostate cancer mortality (HR = 1.21, 95% CI = 1.06 to 1.37). The association with mortality was not modified by screening outcome (Pinteraction = .13). CONCLUSIONS: Within this screened population, individuals with higher BMI had lower risk of prostate cancer diagnosis but higher risk of prostate cancer mortality. As higher BMI was not positively associated with advanced-stage prostate cancer risk, the increased mortality is unlikely to be due to delayed prostate cancer detection.

Association of Frequent Aspirin Use With Ovarian Cancer Risk According to Genetic Susceptibility.

Importance: Frequent aspirin use is associated with reduced ovarian cancer risk, but it is unknown whether genetic factors modify this association. Understanding effect modifiers is important given that any use of aspirin for ovarian cancer chemoprevention will likely need to focus on specific higher-risk subgroups. Objective: To evaluate whether the association between frequent aspirin use and ovarian cancer is modified by a polygenic score (PGS) for nonmucinous ovarian cancer. Design, Setting, and Participants: We pooled individual-level data from 8 population-based case-control studies from the Ovarian Cancer Association Consortium conducted in the US, UK, and Australia between 1995 and 2009. We included case patients and control participants with both genetic data and data on frequent aspirin use. Case patients with mucinous ovarian cancer were excluded. Data were analyzed between November 1, 2021, and July 31, 2022. Exposures: Frequent aspirin use, defined as daily or almost daily use for 6 months or longer. Main Outcomes and Measures: The main outcome was nonmucinous epithelial ovarian cancer. We used logistic regression to estimate odds ratios (ORs) and 95% CIs and likelihood ratio tests to investigate effect modification by the PGS. Results: There were 4476 case patients with nonmucinous ovarian cancer and 6659 control participants included in this analysis. At study enrollment, the median (IQR) age was 58 (50-66) years for case patients and 57 (49-65) years for control participants. Case patients and control participants self-reported that they were Black (122 [3%] vs 218 [3%]), White (3995 [89%] vs 5851 [88%]), or of other race and ethnicity (348 [8%] vs 580 [9%]; race and ethnicity were unknown for 11 [0%] vs 10 [0%]). There were 575 case patients (13%) and 1030 control participants (15%) who reported frequent aspirin use. The 13% reduction in ovarian cancer risk associated with frequent aspirin use (OR, 0.87 [95% CI, 0.76-0.99]) was not modified by the PGS. Consistent ORs were observed among individuals with a PGS less than (0.85 [0.70-1.02]) and greater than (0.86 [0.74-1.01]) the median. Results were similar by histotype. Conclusions and Relevance: The findings of this study suggest that genetic susceptibility to ovarian cancer based on currently identified common genetic variants does not appear to modify the protective association between frequent aspirin use and ovarian cancer risk. Future work should continue to explore the role of aspirin use for ovarian cancer prevention among individuals who are at higher risk for ovarian cancer.

Circulating insulin-like growth factors and risks of overall, aggressive and early-onset prostate cancer: a collaborative analysis of 20 prospective studies and Mendelian randomization analysis.

BACKGROUND: Previous studies had limited power to assess the associations of circulating insulin-like growth factors (IGFs) and IGF-binding proteins (IGFBPs) with clinically relevant prostate cancer as a primary endpoint, and the association of genetically predicted IGF-I with aggressive prostate cancer is not known. We aimed to investigate the associations of IGF-I, IGF-II, IGFBP-1, IGFBP-2 and IGFBP-3 concentrations with overall, aggressive and early-onset prostate cancer. METHODS: Prospective analysis of biomarkers using the Endogenous Hormones, Nutritional Biomarkers and Prostate Cancer Collaborative Group dataset (up to 20 studies, 17 009 prostate cancer cases, including 2332 aggressive cases). Odds ratios (OR) and 95% confidence intervals (CI) for prostate cancer were estimated using conditional logistic regression. For IGF-I, two-sample Mendelian randomization (MR) analysis was undertaken using instruments identified using UK Biobank (158 444 men) and outcome data from PRACTICAL (up to 85 554 cases, including 15 167 aggressive cases). Additionally, we used colocalization to rule out confounding by linkage disequilibrium. RESULTS: In observational analyses, IGF-I was positively associated with risks of overall (OR per 1 SD = 1.09: 95% CI 1.07, 1.11), aggressive (1.09: 1.03, 1.16) and possibly early-onset disease (1.11: 1.00, 1.24); associations were similar in MR analyses (OR per 1 SD = 1.07: 1.00, 1.15; 1.10: 1.01, 1.20; and 1.13; 0.98, 1.30, respectively). Colocalization also indicated a shared signal for IGF-I and prostate cancer (PP4: 99%). Men with higher IGF-II (1.06: 1.02, 1.11) and IGFBP-3 (1.08: 1.04, 1.11) had higher risks of overall prostate cancer, whereas higher IGFBP-1 was associated with a lower risk (0.95: 0.91, 0.99); these associations were attenuated following adjustment for IGF-I. CONCLUSIONS: These findings support the role of IGF-I in the development of prostate cancer, including for aggressive disease.

Analgesic Use and Circulating Estrogens, Androgens, and Their Metabolites in the Women's Health Initiative Observational Study.

Though studies have observed inverse associations between use of analgesics (aspirin, NSAIDs, and acetaminophen) and the risk of several cancers, the potential biological mechanisms underlying these associations are unclear. We investigated the relationship between analgesic use and serum concentrations of estrogens, androgens, and their metabolites among postmenopausal women to provide insights on whether analgesic use might influence endogenous hormone levels, which could in turn influence hormone-related cancer risk. The study included 1,860 postmenopausal women from two case-control studies nested within the Women's Health Initiative Observational Study. Analgesic use was reported at study baseline. Fifteen estrogens and estrogen metabolites and 12 androgens and androgen metabolites were quantified in baseline serum by LC/MS-MS. Linear regression with inverse probability weighting, stratified by menopausal hormone therapy (MHT) use, was used to estimate adjusted geometric mean concentrations of each hormone by analgesic use. Among women not currently using MHT (n = 951), low-dose aspirin (<100 mg) use was associated with a higher serum concentration of estrone, estradiol, and 2, 4, and 16 hydroxylated metabolites. Use of regular-dose aspirin (≥100 mg), non-aspirin NSAIDs, and acetaminophen was not associated with serum concentrations of estrogens, androgens, or their metabolites. This study highlights the importance of examining aspirin use by dose and suggests that low-dose aspirin may influence endogenous estrogen concentrations. PREVENTION RELEVANCE: This study explores a potential pathway by which analgesic medications such as aspirin may prevent hormone-related cancers. The findings support a positive association between low-dose aspirin use and endogenous estrogens, indicating that further elucidation of the interplay between low-dose aspirin, estrogen concentrations, and cancer risk is needed.

Modification of the Association Between Frequent Aspirin Use and Ovarian Cancer Risk: A Meta-Analysis Using Individual-Level Data From Two Ovarian Cancer Consortia.

PURPOSE: Frequent aspirin use has been associated with reduced ovarian cancer risk, but no study has comprehensively assessed for effect modification. We leveraged harmonized, individual-level data from 17 studies to examine the association between frequent aspirin use and ovarian cancer risk, overall and across subgroups of women with other ovarian cancer risk factors. METHODS: Nine cohort studies from the Ovarian Cancer Cohort Consortium (n = 2,600 cases) and eight case-control studies from the Ovarian Cancer Association Consortium (n = 5,726 cases) were included. We used Cox regression and logistic regression to assess study-specific associations between frequent aspirin use (≥ 6 days/week) and ovarian cancer risk and combined study-specific estimates using random-effects meta-analysis. We conducted analyses within subgroups defined by individual ovarian cancer risk factors (endometriosis, obesity, family history of breast/ovarian cancer, nulliparity, oral contraceptive use, and tubal ligation) and by number of risk factors (0, 1, and ≥ 2). RESULTS: Overall, frequent aspirin use was associated with a 13% reduction in ovarian cancer risk (95% CI, 6 to 20), with no significant heterogeneity by study design (P = .48) or histotype (P = .60). Although no association was observed among women with endometriosis, consistent risk reductions were observed among all other subgroups defined by ovarian cancer risk factors (relative risks ranging from 0.79 to 0.93, all P-heterogeneity > .05), including women with ≥ 2 risk factors (relative risk, 0.81; 95% CI, 0.73 to 0.90). CONCLUSION: This study, the largest to-date on aspirin use and ovarian cancer, provides evidence that frequent aspirin use is associated with lower ovarian cancer risk regardless of the presence of most other ovarian cancer risk factors. Risk reductions were also observed among women with multiple risk factors, providing proof of principle that chemoprevention programs with frequent aspirin use could target higher-risk subgroups.

An Up-to-date Assessment of US Prostate Cancer Incidence Rates by Stage and Race: A Novel Approach Combining Multiple Imputation with Age and Delay Adjustment.

BACKGROUND: In the USA, it is unknown whether metastatic prostate cancer incidence has continued to increase and whether racial differences have persisted. OBJECTIVE: Combining multiple imputation with age and delay adjustment, we provide an up-to-date, comprehensive assessment of US prostate cancer incidence trends by stage and race. DESIGN, SETTING, AND PARTICIPANTS: From Surveillance Epidemiology and End Results (SEER)-18, 774 240 prostate cancer cases were diagnosed during 2004-2017. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Multiple imputation assigned prostate cancer stage to the 4.7% of cases with missing stage, which varied by year and race-ethnicity. SEER delay factors adjusted case counts to anticipated future data corrections. Twenty datasets were imputed, and Rubin's rules were used for summary estimation. Overall and stage-specific rates were estimated and stratified by race and age group. Joinpoint software identified significant temporal changes and estimated annual percentage changes. We compared these estimates without multiple imputation and delay adjustment. RESULTS AND LIMITATIONS: Metastatic prostate cancer incidence increased during 2011-2017, with an annual percentage change of 5.5. This was followed by increases in localized and regional disease since 2014. Non-Hispanic black men continued to have the highest incidence, especially for metastatic disease. The increasing rate of metastatic prostate cancer in non-Hispanic white men aged 50-74 yr accelerated recently, and the incidence was 56% higher in 2017 than in 2004. Rates without multiple imputation and delay adjustment were quantitatively and qualitatively different. This observational study is unable to assign causes to observed changes in prostate cancer incidence. CONCLUSIONS: Multiple imputation and delay adjustment are essential for portraying accurately stage- and race-specific prostate cancer incidence as clinical practice evolves. PATIENT SUMMARY: In the USA, diagnosis of prostate cancer that has spread to distant sites (metastatic disease) continues to increase. Black men continue to have higher risks of being diagnosed with metastatic prostate cancer than other race-ethnicities.