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PURPOSE Orteronel (TAK-700) is a nonsteroidal 17,20-lyase inhibitor suppressing androgen synthesis. We evaluated the clinical benefit of orteronel when added to androgen deprivation therapy (ADT) in patients with newly diagnosed metastatic hormone-sensitive prostate cancer. METHODS In this open-label randomized phase III study, patients with metastatic hormone-sensitive prostate cancer were randomly assigned 1:1 to ADT with orteronel (300 mg oral twice daily; experimental arm) or ADT with bicalutamide (50 mg oral once daily; control arm). The primary objective was the comparison of overall survival (OS), targeting a 33% improvement in median survival. A stratified log-rank test with a one-sided P ≤ .022 would indicate statistical significance. Secondary end points were progression-free survival (PFS), prostate-specific antigen (PSA) level at 7 months (≤ 0.2 v 0.2 to ≤ 4 v > 4 ng/mL), and adverse event profile. RESULTS Among 1,279 patients included in the analysis, 638 were randomly assigned to the ADT plus orteronel arm and 641 to the control arm. The median age was 68 years; 49% had extensive disease. After a median follow-up of 4.9 years, there was a significant improvement in PFS (median 47.6 v 23.0 months, hazard ratio 0.58; 95% CI, 0.51 to 0.67; P < .0001) and PSA response at 7 months ( P < .0001), but not in OS (median 81.1 v 70.2 months, hazard ratio 0.86; 95% CI, 0.72 to 1.02; P = .040, one-sided). More grade 3/4 adverse events occurred in the experimental versus the control arms (43% v 14%). Postprotocol life-prolonging therapy was received by 77.4% of patients in the control arm and 61.3% of patients in the orteronel arm. CONCLUSION The study did not meet the primary end point of improved OS with orteronel. The lack of correlation of PFS and PSA response with OS raises concerns over assumption of their consistent surrogacy for OS in the context of extensive postprotocol therapy in this setting.

Background: Multivitamin (MVI) use is a common health behavior but there is conflicting evidence from prospective studies about whether this behavior increases or decreases prostate cancer risk. Methods: Associations of MVI use and prostate cancer risk were evaluated using data from the Selenium and Vitamin E Cancer Prevention Trial (SELECT). Cox proportional hazards models estimated associations of MVI use with risk of total, low-, and high-grade prostate cancer. Longitudinal data were used to evaluate screening and biopsy patterns. To account for differential biopsy patterns, the probability of prostate cancer was estimated for men with a positive screening value but no biopsy. Incidence density ratios were used to approximate HRs, and associations of MVI use with predicted prostate cancer risk were compared with observed. Results: Analyses of data from observed biopsies suggest a respective 19% (95% confidence interval, 10%–28%) and 21% (12%–31%) higher risk of high-grade prostate cancer for current and long-term MVI use, compared with no use. Current and long-term MVI use was associated with a shorter time to first on-study biopsy, indicating the potential for detection bias. After accounting for differential acceptance of biopsy, associations of MVI use with prostate cancer were attenuated and not statistically significant. Conclusions: In SELECT, biopsy acceptance patterns differed by MVI use. Estimates of associations of MVI use with prostate cancer risk based on observed biopsy data may be biased by differential acceptance of biopsy. Impact: Differential biopsy ascertainment may impact associations of risk factors and prostate cancer. Detailed screening and biopsy data can be used to analytically minimize such bias.

We sought to determine if absolute prostate specific antigen (PSA) value after 6 months of androgen deprivation therapy (ADT) is predictive of subsequent survival in patients with prostate adenocarcinoma.We performed a retrospective review of men receiving care within the Veterans Health Administration who initiated ADT for prostate adenocarcinoma. We used low- (≤0.2 ng/ml), intermediate- (0.2 to 4 ng/ml) and high-risk (4 ng/ml) absolute PSA values after 6-9 months of ADT, previously described in Southwest Oncology Group trial 9346. The primary endpoints were all-cause mortality and prostate cancer-specific mortality (PCSM). Kaplan-Meier survival curves for each PSA category were estimated and log-rank test was conducted. We employed Cox regression analysis adjusted for covariates and inverse propensity score weights associated with PSA categories to estimate the PSA category association with PCSM and all-cause mortality.We identified 9,170 patients in our cohort. Following ADT induction, 3,508 patients had low, 3,419 had intermediate and 2,243 had high PSA values. Two- and 5-year survival rates for low, intermediate and high PSA groups were 93.9% and 85.2% vs 88.6% and 71.2% vs 63.6% and 38.6%, respectively (p0.0001). Patients in the high and intermediate PSA categories had a 15-fold and 3-fold higher risk of PCSM compared to those with PSA0.2 ng/ml (p0.0001).Absolute PSA in hormone-sensitive prostate cancer after 6-9 months of ADT is a predictor of overall mortality and PCSM. This measure can rapidly assess the efficacy of new interventions in phase 2 clinical trials.

Cribriform growth pattern is well-established as an adverse pathologic feature in prostate cancer. The literature suggests "large" cribriform glands associate with aggressive behavior; however, published studies use varying definitions for "large". We aimed to identify an outcome-based quantitative cut-off for "large" vs "small" cribriform glands. We conducted an initial training phase using the tissue microarray based Canary retrospective radical prostatectomy cohort. Of 1287 patients analyzed, cribriform growth was observed in 307 (24%). Using Kaplan-Meier estimates of recurrence-free survival curves (RFS) that were stratified by cribriform gland size, we identified 0.25 mm as the optimal cutoff to identify more aggressive disease. In univariable and multivariable Cox proportional hazard analyses, size >0.25 mm was a significant predictor of worse RFS compared to patients with cribriform glands ≤0.25 mm, independent of pre-operative PSA, grade, stage and margin status (p 0.25 mm had a significantly lower RFS relative to patients with cribriform glands ≤0.25 mm (each subset p = 0.004). Furthermore, there was no significant difference in outcomes between patients with cribriform glands ≤ 0.25 mm and patients without cribriform glands. The >0.25 mm cut-off was validated as statistically significant in a separate 419 patient, completely embedded whole-section radical prostatectomy cohort by biochemical recurrence, metastasis-free survival, and disease specific death, even when cases with admixed Gleason pattern 5 carcinoma were excluded. In summary, our findings support reporting cribriform gland size and identify 0.25 mm as an optimal outcome-based quantitative measure for defining "large" cribriform glands. Moreover, cribriform glands >0.25 mm are associated with potential for metastatic disease independent of Gleason pattern 5 adenocarcinoma.

Mutations in several common hereditary cancer genes are associated with prostate cancer, but there is limited information on the prevalence of these mutations in Hispanic men.We selected men at high risk for genetic mutations from 1515 Hispanic men enrolled in the San Antonio Biomarkers of Risk for prostate cancer (SABOR) cohort. Inclusion criteria included men with a diagnosis of prostate cancer or a first-degree family history of prostate cancer. We performed germline genetic testing using the Color Genomics platform, sequencing 30 genes associated with hereditary cancer risk. Additionally, we assessed ancestral informative markers to determine the admixture of the ethnically unique cohort.Of the 275 subjects who met selection criteria, 263 patients had sufficient samples for sequencing. We identified 3.8% of patients (10 of 263) with a pathogenic or likely pathogenic mutation in the 30 genes tested, of whom 70% would not have met established criteria for genetic testing. Six of these mutations were in BRCA1/2 or ATM. There was a significant inverse association between the percentage of Native American ancestry and the risk of prostate cancer, OR 0.11 (95% CI 0.02-0.76, P = .025).Hispanic men with either a personal or family history of prostate cancer carry mutations in hereditary cancer genes at a significant rate, on par with non-Hispanic counterparts with similar risk factors.

Perspective from Pathologic Characteristics of Cancers Detected in the Prostate Cancer Prevention Trial: Implications for Prostate Cancer Detection and Chemoprevention

No approved medical therapies prevent progression of low-grade prostate cancer. Rapamycin inhibits cell proliferation and augments immune responses, producing an antitumor effect. Encapsulated rapamycin (eRapa) incorporates rapamycin into a pH-sensitive polymer, ensuring consistent dosing. Here, we present results from a phase I trial evaluating the safety and tolerability of eRapa in patients with prostate cancer. Patients with Gleason ≤7 (3+4) disease (low and intermediate risk) under active surveillance were enrolled in a 3+3 study with three eRapa dosing cohorts (cohort 1, 0.5 mg/week; cohort 2, 1 mg/week; and cohort 3, 0.5 mg/day). Patients were treated for 3 months and followed for an additional 3 months to assess safety, pharmacokinetics, quality of life (QoL), immune response, and disease progression. Fourteen patients (cohort 1, n = 3; cohort 2, n = 3; and cohort 3, n = 8) were enrolled. In cohort 3, one dose-limiting toxicity (DLT; neutropenia) and two non-DLT grade 1–2 adverse events (AE) occurred that resulted in patient withdrawal. All AEs in cohorts 1 and 2 were grade 1. Peak serum rapamycin concentration was 7.1 ng/mL after a 1 mg dose. Stable trough levels (∼2 ng/mL) developed after 48–72 hours. Daily dosing mildly worsened QoL, although QoL recovered after treatment cessation in all categories, except fatigue. Weekly dosing increased naïve T-cell populations. Daily dosing increased central memory cell populations and exhaustion markers. No disease progression was observed. In conclusion, treatment with eRapa was safe and well-tolerated. Daily dosing produced higher frequencies of lower grade toxicities and transient worsening of QoL, while weekly dosing impacted immune response. Future studies will verify clinical benefit and long-term tolerability.Prevention Relevance: There is an unmet medical need for a well-tolerated treatment capable of delaying progression of newly diagnosed low-grade prostate cancer. This treatment would potentially obviate the need for future surgical intervention and improve the perception of active surveillance as a more acceptable option among this patient population.

Inflammation may play an etiologic role in prostate cancer. Several dietary factors influence inflammation; studies have shown that long-chain n-3 polyunsaturated fatty acids are anti-inflammatory, whereas n-6 and trans fatty acids are proinflammatory. We evaluated whether serum phospholipid n-3, n-6, and trans fatty acids were associated with intraprostatic inflammation, separately in 191 prostate cancer cases and 247 controls from the placebo arm of the Prostate Cancer Prevention Trial (PCPT). Men without a prostate cancer diagnosis underwent prostate biopsy at trial end, and benign prostate tissue inflammation was evaluated in approximately three biopsy cores per man; this was expressed as no, some, or all cores with inflammation. In controls, serum eicosapentaenoic acid [OR of all cores with inflammation versus none (95% CI), 0.35 (0.14–0.89)] and docosahexaenoic acid [OR (95% CI), 0.42 (0.17–1.02)] were inversely associated with, whereas linoleic acid [OR (95% CI), 3.85 (1.41–10.55)] was positively associated with intraprostatic inflammation. Serum trans fatty acids were not associated with intraprostatic inflammation. No significant associations were observed in cases; however, we could not rule out a positive association with linoleic acid and an inverse association with arachidonic acid. Thus, in the PCPT, we found that serum n-3 fatty acids were inversely, n-6 fatty acids were positively, and trans fatty acids were not associated with intraprostatic inflammation in controls. Although, in theory, inflammation could mediate associations of serum fatty acids with prostate cancer risk, our findings cannot explain the epidemiologic associations observed with n-3 and n-6 fatty acids. Cancer Prev Res; 8(7); 590–6. ©2015 AACR.

Supplementary Tables 1-3. Supplementary Table 1. Characteristics1 of cases2 with and without inflammation in prostate biopsy cores, in the placebo arm of the Prostate Cancer Prevention Trial. Supplementary Table 2. Distribution of serum phospholipid fatty acids by percent of total among cases with and without inflammation in prostate biopsy cores, in the placebo arm of the Prostate Cancer Prevention Trial. Supplementary Table 3. Multivariable-adjusted associations of serum phospholipid fatty acids in relation to inflammation in prostate biopsy cores, among cases from the placebo arm of the Prostate Cancer Prevention Trial.

Supplementary Table

The Selenium and Vitamin E Cancer Prevention Trial (SELECT) showed higher prostate cancer incidence in men supplemented with high-dose α-tocopherol. We, therefore, examined whether presupplementation plasma α-tocopherol or γ-tocopherol was associated with overall or high-grade prostate cancer. A stratified case–cohort sample that included 1,746 incident prostate cancer cases diagnosed through June 2009 and a subcohort of 3,211 men was derived from the SELECT trial of 35,533 men. Plasma was collected at entry from 2001 to 2004, and median follow-up was 5.5 years (range, 0–7.9 years). Incidence of prostate cancer as a function of plasma α-tocopherol, γ-tocopherol, and supplementation with α-tocopherol or selenomethionine was estimated by the hazard ratio (HR). Plasma γ-tocopherol was not associated with prostate cancer. Men with higher α-tocopherol concentrations seemed to have risk similar to that of men with lower concentrations [overall HR for fifth (Q5) vs. first quintile (Q1), 1.21; 95 % confidence interval (CI), 0.88–1.66; P-trend = 0.24; in the trial placebo arm, Q5 HR, 0.85; 95% CI, 0.44–1.62; P-trend = 0.66]. We found a strong positive plasma α-tocopherol association among men receiving the trial selenomethionine supplement [Q5 HR, 2.04; 95% CI, 1.29–3.22; P-trend = 0.005]. A positive plasma α-tocopherol–prostate cancer association also seemed limited to high-grade disease (Gleason grade, 7–10; overall Q5 HR, 1.59; 95% CI, 1.13–2.24; P-trend = 0.001; among men receiving selenomethionine, Q5 HR, 2.12; 95% CI, 1.32–3.40; P-trend = 0.0002). Our findings indicate that higher plasma α-tocopherol concentrations may interact with selenomethionine supplements to increase high-grade prostate cancer risk, suggesting a biologic interaction between α-tocopherol and selenium itself or selenomethionine. Cancer Prev Res; 7(9); 886–95. ©2014 AACR.

Supplementary Table 1

Finasteride taken for 7 years in the Prostate Cancer Prevention Trial (PCPT) reduced the risk of prostate cancer by 25%, but with an apparent increased risk of high-grade disease. Subsequent analyses found that finasteride biases toward improved prostate cancer detection and accuracy in prostate cancer grading at biopsy. In our first analysis of the present study, we accounted for these biases in estimating the effect of finasteride on the risk of overall and high-grade prostate cancer. This analysis used PCPT data that included 3-month longer collection of endpoints than in the original report with observed prostate cancer rates of 22.9% (4.8% with high grade; placebo) versus 16.6% (5.8% with high grade; finasteride). Based on these updated results, the bias-adjusted prostate cancer rates are estimated to be 21.1% (4.2% high grade; placebo) and 14.7% (4.8% high grade; finasteride), a 30% risk reduction in prostate cancer [relative risk (RR), 0.70; 95% confidence interval (95% CI), 0.64-0.76; P < 0.0001] and a nonsignificant 14% increase in high-grade cancer (RR, 1.14; 95% CI, 0.96-1.35; P = 0.12) with finasteride. We then estimated rates of high-grade prostate cancer based on an analysis that incorporated grading information from radical prostatectomies in 500 subjects diagnosed with cancer. The resulting estimates were high-grade cancer rates of 8.2% (placebo) versus 6.0% (finasteride), a 27% risk reduction (RR, 0.73; 95% CI, 0.56-0.96; P = 0.02) with finasteride. Our third analysis examined the impact of biopsy sensitivity on the relative risk of high-grade prostate cancer and found that differential sensitivity of biopsy between the treatment arms can have a significant impact on risk ratio estimates. These collective results suggest that the observed, unadjusted higher risk of high-grade disease with finasteride seems to have been due to facilitated diagnosis resulting primarily from increased biopsy sensitivity with finasteride. Therefore, men undergoing regular prostate cancer screening or who express an interest in cancer prevention should be informed of the opportunity to take finasteride for preventing prostate cancer.

Aspirin and statin use may lower the risk of advanced/fatal prostate cancer, possibly by reducing intraprostatic inflammation. To test this hypothesis, we investigated the association of aspirin and statin use with the presence and extent of intraprostatic inflammation, and the abundance of specific immune cell types, in benign prostate tissue from a subset of men from the placebo arm of the Prostate Cancer Prevention Trial. Men were classified as aspirin or statin users if they reported use at baseline or during the 7-year trial. Presence and extent of inflammation were assessed, and markers of specific immune cell types (CD4, CD8, FoxP3, CD68, and c-KIT) were scored, in slides from end-of-study prostate biopsies taken irrespective of clinical indication, per trial protocol. Logistic regression was used to estimate associations between medication use and inflammation measures, adjusted for potential confounders. Of 357 men included, 61% reported aspirin use and 32% reported statin use. Prevalence and extent of inflammation were not associated with medication use. However, aspirin users were more likely to have low FoxP3, a T regulatory cell marker [OR, 5.60; 95% confidence interval (CI), 1.16–27.07], and statin users were more likely to have low CD68, a macrophage marker (OR, 1.63; 95% CI, 0.81–3.27). If confirmed, these results suggest that these medications may alter the immune milieu of the prostate, which could potentially mediate effects of these medications on advanced/fatal prostate cancer risk.

Finasteride and Prostate Cancer: New York Times Article from Pathologic Characteristics of Cancers Detected in the Prostate Cancer Prevention Trial: Implications for Prostate Cancer Detection and Chemoprevention

Supplemental File 2

Supplementary Table S1: Case-cohort stratified sample, SELECT case-cohort study Supplementary Table S2: Baseline demographic and health related characteristics by quintiles of plasma α-tocopherol and γ-tocopherol, SELECT case-cohort study Supplementary Table S3. Association between quintiles of plasma α-tocopherol and prostate cancer risk - joint effects model by intervention group, SELECT case-cohort study Supplementary Table S4. Association between quintiles of plasma γ-tocopherol and prostate cancer risk stratified by Gleason grade, smoking status, and follow-up time, SELECT case-cohort study

Supplemental Table 1

Supplemental Table 2

Supplemental File 1

Supplementary Tables 1-5

Finasteride and Prostate Cancer: New York Times Article from Finasteride Does Not Increase the Risk of High-Grade Prostate Cancer: A Bias-Adjusted Modeling Approach

Vitamin D may influence prostate cancer risk, but evidence is inconsistent. We conducted a nested case–control study in the Prostate Cancer Prevention Trial (PCPT). Cases (n = 1,128) and controls (n = 1,205) were frequency matched on age, first-degree relative with prostate cancer, and PCPT treatment arm (finasteride/placebo); African-Americans were oversampled and case/control status was biopsy confirmed. We selected 21 SNPs in vitamin D–related genes (VDR, GC, C10orf88, CYP2R1, CYP24A1, CYP27B1, DHCR7, and NADSYN1) to test genotype and genotype–treatment interactions in relation to prostate cancer. We also tested mean serum 25(OH)D differences by minor allele distributions and tested for serum 25(OH)D–genotype interactions in relation to prostate cancer risk. Log-additive genetic models (Bonferroni-corrected within genes) adjusted for age, body mass index, PSA, and family history of prostate cancer revealed a significant interaction between treatment arm and GC/rs222016 (finasteride OR = 1.37, placebo OR = 0.85; Pinteraction < 0.05), GC/rs222014 (finasteride OR = 1.36, placebo OR = 0.85; Pinteraction < 0.05), and CYP27B1/rs703842 (finasteride OR = 0.76, placebo OR = 1.10; Pinteraction < 0.05) among Caucasians, and C10orf88/rs6599638 (finasteride OR = 4.68, placebo OR = 1.39; Pinteraction < 0.05) among African-Americans. VDR/rs1544410 and CYP27B1/rs703842 had significant treatment interactions for high-grade disease among Caucasians (finasteride OR = 0.81, placebo OR = 1.40; Pinteraction < 0.05 and finasteride OR = 0.70, placebo OR = 1.28; Pinteraction < 0.05, respectively). Vitamin D–related SNPs influenced serum 25(OH)D, but gene-serum 25(OH)D effect modification for prostate cancer was marginally observed only for CYP24A1/rs2248359. In conclusion, evidence that vitamin D–related genes or gene-serum 25(OH)D associations influence prostate cancer risk is modest. We found some evidence for gene–finasteride interaction effects for prostate cancer in Caucasians and African-Americans. Results suggest only minimal associations of vitamin D with total or high-grade prostate cancer.

Perspective from Finasteride Does Not Increase the Risk of High-Grade Prostate Cancer: A Bias-Adjusted Modeling Approach

The adjustments include covariates: age, HbA1c, Charlson comorbidity, finasteride use, and statin use, and propensity scores for metformin use.

Supplemental Table 3

Supplemental figures 1 and 2. Supplemental tables 1-7.

Supplemental Table 1: Minor allele frequencies and Hardy Weinberg Equilibrium (HWE) p-values for SNPs across antioxidant & transport related genes. Supplemental Table 2: Full results for the associations between antioxidant SNPs x selenium supplementation. Supplemental Table 3: Full results for the associations between antioxidant, transport, & DNA repair SNPs x vitamin E supplementation and risk of high-grade and overall prostate cancer (N=1,538) in SELECT. Supplemental Table 4: Full results for the independent associations of SNPs and risk high-grade and overall prostate cancer in the placebo arm of SELECT.

COXEN Model development

PDF file, 58K, PSA testing and abnormal PSA result by primary care clinic.

Background: Genome-wide association studies (GWAS) have identified numerous prostate cancer susceptibility alleles, but these loci have been identified primarily in men of European descent. There is limited information about the role of these loci in men of African descent.Methods: We identified 7,788 prostate cancer cases and controls with genotype data for 47 GWAS-identified loci.Results: We identified significant associations for SNP rs10486567 at JAZF1, rs10993994 at MSMB, rs12418451 and rs7931342 at 11q13, and rs5945572 and rs5945619 at NUDT10/11. These associations were in the same direction and of similar magnitude as those reported in men of European descent. Significance was attained at all reported prostate cancer susceptibility regions at chromosome 8q24, including associations reaching genome-wide significance in region 2.Conclusion: We have validated in men of African descent the associations at some, but not all, prostate cancer susceptibility loci originally identified in European descent populations. This may be due to the heterogeneity in genetic etiology or in the pattern of genetic variation across populations.Impact: The genetic etiology of prostate cancer in men of African descent differs from that of men of European descent. Cancer Epidemiol Biomarkers Prev; 20(1); 23–32. ©2011 AACR.

Supplementary Materials from Validation of Genome-Wide Prostate Cancer Associations in Men of African Descent

Supplemental Table 1. Calculation of individual drug scores for COXEN

Supplemental Table 2. Comparing GC and DDMVAC for Pathologic Response at Cystectomy - intention to treat analysis

Aggressive tumors of epithelial origin shed cells that intravasate and become circulating tumor cells (CTC). The CTCs that are able to survive the stresses encountered in the bloodstream can then seed metastases. We demonstrated previously that CTCs isolated from the blood of prostate cancer patients display specific nanomechanical phenotypes characteristic of cell endurance and invasiveness and patient sensitivity to androgen deprivation therapy. Here we report that patient-isolated CTCs are nanomechanically distinct from cells randomly shed from the tumor, with high adhesion as the most distinguishing biophysical marker. CTCs uniquely coisolated with macrophage-like cells bearing the markers of tumor-associated macrophages (TAM). The presence of these immune cells was indicative of a survival-promoting phenotype of “mechanical fitness” in CTCs based on high softness and high adhesion as determined by atomic force microscopy. Correlations between enumeration of macrophages and mechanical fitness of CTCs were strong in patients before the start of hormonal therapy. Single-cell proteomic analysis and nanomechanical phenotyping of tumor cell–macrophage cocultures revealed that macrophages promoted epithelial–mesenchymal plasticity in prostate cancer cells, manifesting in their mechanical fitness. The resulting softness and adhesiveness of the mechanically fit CTCs confer resistance to shear stress and enable protective cell clustering. These findings suggest that selected tumor cells are coached by TAMs and accompanied by them to acquire intermediate epithelial/mesenchymal status, thereby facilitating survival during the critical early stage leading to metastasis.Significance:The interaction between macrophages and circulating tumor cells increases the capacity of tumor cells to initiate metastasis and may constitute a new set of blood-based targets for pharmacologic intervention.

Background: Several prospective studies suggest that use of cholesterol-lowering statin drugs is inversely associated with advanced stage and possibly high-grade prostate cancer. One study reported that men with low cholesterol had a lower risk of high-grade prostate cancer. Given these findings, we investigated the association between low serum cholesterol and prostate cancer risk in the Prostate Cancer Prevention Trial.Methods: We conducted a cohort study of 5,586 men ages ≥55 years who were randomized to the placebo arm of the Prostate Cancer Prevention Trial between 1993 and 1996. Serum cholesterol was measured enzymatically at entry. By the end of follow-up, 1,251 prostate cancer cases were confirmed. We used logistic regression to calculate the multivariable odds ratio (OR) of total, and Gleason 2 to 6 (n = 993), 7 (n = 199), and 8 to 10 (n = 59) prostate cancer comparing low serum (normal, Results: Men with low cholesterol had a lower risk of Gleason 8 to 10 prostate cancer [OR, 0.41; 95% confidence interval (CI), 0.22-0.77] than men with high cholesterol. No association was present for prostate cancer overall (OR, 0.97; 95% CI, 0.85-1.11), Gleason 2 to 6 disease (OR, 1.03; 95% CI, 0.89-1.18), or Gleason 7 disease (OR, 0.93; 95% CI, 0.69-1.24).Conclusion: These prospective results support that men with low cholesterol have a reduced risk of high-grade prostate cancer. These and other contemporary data that suggest that cholesterol metabolism should be investigated further in the etiology of prostate cancer. (Cancer Epidemiol Biomarkers Prev 2009;18(11):2807–13)