A comparison of sunitinib with cabozantinib, crizotinib, and savolitinib for treatment of advanced papillary renal cell carcinoma: a randomised, open-label, phase 2 trial

BACKGROUND

MET (also known as hepatocyte growth factor receptor) signalling is a key driver of papillary renal cell carcinoma (PRCC). Given that no optimal therapy for metastatic PRCC exists, we aimed to compare an existing standard of care, sunitinib, with the MET kinase inhibitors cabozantinib, crizotinib, and savolitinib for treatment of patients with PRCC.

METHODS

We did a randomised, open-label, phase 2 trial done in 65 centres in the USA and Canada. Eligible patients were aged 18 years or older with metastatic PRCC who had received up to one previous therapy (excluding vascular endothelial growth factor-directed and MET-directed agents). Patients were randomly assigned to receive sunitinib, cabozantinib, crizotinib, or savolitinib, with stratification by receipt of previous therapy and PRCC subtype. All drug doses were administered orally: sunitinib 50 mg, 4 weeks on and 2 weeks off (dose reductions to 37·5 mg and 25 mg allowed); cabozantinib 60 mg daily (reductions to 40 mg and 20 mg allowed); crizotinib 250 mg twice daily (reductions to 200 mg twice daily and 250 mg once daily allowed); and savolitinib 600 mg daily (reductions to 400 mg and 200 mg allowed). Progression-free survival (PFS) was the primary endpoint. Analyses were done in an intention-to-treat population, with patients who did not receive protocol therapy excluded from safety analyses. This trial is registered with ClinicalTrials.gov, NCT02761057.

FINDINGS

Between April 5, 2016, and Dec 15, 2019, 152 patients were randomly assigned to one of four study groups. Five patients were identified as ineligible post-randomisation and were excluded from these analyses, resulting in 147 eligible patients. Assignment to the savolitinib (29 patients) and crizotinib (28 patients) groups was halted after a prespecified futility analysis; planned accrual was completed for both sunitinib (46 patients) and cabozantinib (44 patients) groups. PFS was longer in patients in the cabozantinib group (median 9·0 months, 95% CI 6-12) than in the sunitinib group (5·6 months, 3-7; hazard ratio for progression or death 0·60, 0·37-0·97, one-sided p=0·019). Response rate for cabozantinib was 23% versus 4% for sunitinib (two-sided p=0·010). Savolitinib and crizotinib did not improve PFS compared with sunitinib. Grade 3 or 4 adverse events occurred in 31 (69%) of 45 patients receiving sunitinib, 32 (74%) of 43 receiving cabozantinib, ten (37%) of 27 receiving crizotinib, and 11 (39%) of 28 receiving savolitinib; one grade 5 thromboembolic event was recorded in the cabozantinib group.

INTERPRETATION

Cabozantinib treatment resulted in significantly longer PFS compared with sunitinib in patients with metastatic PRCC.

FUNDING

National Institutes of Health and National Cancer Institute.

Phase I Trial of Encapsulated Rapamycin in Patients with Prostate Cancer Under Active Surveillance to Prevent Progression

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.

Trans-ancestry genome-wide association meta-analysis of prostate cancer identifies new susceptibility loci and informs genetic risk prediction

Prostate cancer is a highly heritable disease with large disparities in incidence rates across ancestry populations. We conducted a multiancestry meta-analysis of prostate cancer genome-wide association studies (107,247 cases and 127,006 controls) and identified 86 new genetic risk variants independently associated with prostate cancer risk, bringing the total to 269 known risk variants. The top genetic risk score (GRS) decile was associated with odds ratios that ranged from 5.06 (95% confidence interval (CI), 4.84-5.29) for men of European ancestry to 3.74 (95% CI, 3.36-4.17) for men of African ancestry. Men of African ancestry were estimated to have a mean GRS that was 2.18-times higher (95% CI, 2.14-2.22), and men of East Asian ancestry 0.73-times lower (95% CI, 0.71-0.76), than men of European ancestry. These findings support the role of germline variation contributing to population differences in prostate cancer risk, with the GRS offering an approach for personalized risk prediction.

Mendelian Randomization Analysis of n-6 Polyunsaturated Fatty Acid Levels and Pancreatic Cancer Risk

BACKGROUND

Whether circulating polyunsaturated fatty acid (PUFA) levels are associated with pancreatic cancer risk is uncertain. Mendelian randomization (MR) represents a study design using genetic instruments to better characterize the relationship between exposure and outcome.

METHODS

We utilized data from genome-wide association studies within the Pancreatic Cancer Cohort Consortium and Pancreatic Cancer Case-Control Consortium, involving approximately 9,269 cases and 12,530 controls of European descent, to evaluate associations between pancreatic cancer risk and genetically predicted plasma n-6 PUFA levels. Conventional MR analyses were performed using individual-level and summary-level data.

RESULTS

Using genetic instruments, we did not find evidence of associations between genetically predicted plasma n-6 PUFA levels and pancreatic cancer risk [estimates per one SD increase in each PUFA-specific weighted genetic score using summary statistics: linoleic acid odds ratio (OR) = 1.00, 95% confidence interval (CI) = 0.98-1.02; arachidonic acid OR = 1.00, 95% CI = 0.99-1.01; and dihomo-gamma-linolenic acid OR = 0.95, 95% CI = 0.87-1.02]. The OR estimates remained virtually unchanged after adjustment for covariates, using individual-level data or summary statistics, or stratification by age and sex.

CONCLUSIONS

Our results suggest that variations of genetically determined plasma n-6 PUFA levels are not associated with pancreatic cancer risk.

IMPACT

These results suggest that modifying n-6 PUFA levels through food sources or supplementation may not influence risk of pancreatic cancer.

Tailoring Intensity of Active Surveillance for Low-Risk Prostate Cancer Based on Individualized Prediction of Risk Stability

Importance

Active surveillance is increasingly recognized as the preferred standard of care for men with low-risk prostate cancer. However, active surveillance requires repeated assessments, including prostate-specific antigen tests and biopsies that may increase anxiety, risk of complications, and cost.

Objective

To identify and validate clinical parameters that can identify men who can safely defer follow-up prostate cancer assessments.

Design, Setting, and Participants

The Canary Prostate Active Surveillance Study (PASS) is a multicenter, prospective active surveillance cohort study initiated in July 2008, with ongoing accrual and a median follow-up period of 4.1 years. Men with prostate cancer managed with active surveillance from 9 North American academic medical centers were enrolled. Blood tests and biopsies were conducted on a defined schedule for least 5 years after enrollment. Model validation was performed among men at the University of California, San Francisco (UCSF) who did not enroll in PASS. Men with Gleason grade group 1 prostate cancer diagnosed since 2003 and enrolled in PASS before 2017 with at least 1 confirmatory biopsy after diagnosis were included. A total of 850 men met these criteria and had adequate follow-up. For the UCSF validation study, 533 active surveillance patients meeting the same criteria were identified. Exclusion criteria were treatment within 6 months of diagnosis, diagnosis before 2003, Gleason grade score of at least 2 at diagnosis or first surveillance biopsy, no surveillance biopsy, or missing data.

Exposures

Active surveillance for prostate cancer.

Main Outcomes and Measures

Time from confirmatory biopsy to reclassification, defined as Gleason grade group 2 or higher on subsequent biopsy.

Results

A total of 850 men (median [interquartile range] age, 64 [58-68] years; 774 [91%] White) were included in the PASS cohort. A total of 533 men (median [interquartile range] age, 61 [57-65] years; 422 [79%] White) were included in the UCSF cohort. Parameters predictive of reclassification on multivariable analysis included maximum percent positive cores (hazard ratio [HR], 1.30 [95% CI, 1.09-1.56]; P = .004), history of any negative biopsy after diagnosis (1 vs 0: HR, 0.52 [95% CI, 0.38-0.71]; P < .001 and ≥2 vs 0: HR, 0.18 [95% CI, 0.08-0.4]; P < .001), time since diagnosis (HR, 1.62 [95% CI, 1.28-2.05]; P < .001), body mass index (HR, 1.08 [95% CI, 1.05-1.12]; P < .001), prostate size (HR, 0.40 [95% CI, 0.25-0.62]; P < .001), prostate-specific antigen at diagnosis (HR, 1.51 [95% CI, 1.15-1.98]; P = .003), and prostate-specific antigen kinetics (HR, 1.46 [95% CI, 1.23-1.73]; P < .001). For prediction of nonreclassification at 4 years, the area under the receiver operating curve was 0.70 for the PASS cohort and 0.70 for the UCSF validation cohort. This model achieved a negative predictive value of 0.88 (95% CI, 0.83-0.94) for those in the bottom 25th percentile of risk and of 0.95 (95% CI, 0.89-1.00) for those in the bottom 10th percentile.

Conclusions and Relevance

In this study, among men with low-risk prostate cancer, heterogeneity prevailed in risk of subsequent disease reclassification. These findings suggest that active surveillance intensity can be modulated based on an individual's risk parameters and that many men may be safely monitored with a substantially less intensive surveillance regimen.

African-specific improvement of a polygenic hazard score for age at diagnosis of prostate cancer

Polygenic hazard score (PHS) models are associated with age at diagnosis of prostate cancer. Our model developed in Europeans (PHS46) showed reduced performance in men with African genetic ancestry. We used a cross-validated search to identify single nucleotide polymorphisms (SNPs) that might improve performance in this population. Anonymized genotypic data were obtained from the PRACTICAL consortium for 6253 men with African genetic ancestry. Ten iterations of a 10-fold cross-validation search were conducted to select SNPs that would be included in the final PHS46+African model. The coefficients of PHS46+African were estimated in a Cox proportional hazards framework using age at diagnosis as the dependent variable and PHS46, and selected SNPs as predictors. The performance of PHS46 and PHS46+African was compared using the same cross-validated approach. Three SNPs (rs76229939, rs74421890 and rs5013678) were selected for inclusion in PHS46+African. All three SNPs are located on chromosome 8q24. PHS46+African showed substantial improvements in all performance metrics measured, including a 75% increase in the relative hazard of those in the upper 20% compared to the bottom 20% (2.47-4.34) and a 20% reduction in the relative hazard of those in the bottom 20% compared to the middle 40% (0.65-0.53). In conclusion, we identified three SNPs that substantially improved the association of PHS46 with age at diagnosis of prostate cancer in men with African genetic ancestry to levels comparable to Europeans.

Genome-Wide Association Study Data Reveal Genetic Susceptibility to Chronic Inflammatory Intestinal Diseases and Pancreatic Ductal Adenocarcinoma Risk

Registry-based epidemiologic studies suggest associations between chronic inflammatory intestinal diseases and pancreatic ductal adenocarcinoma (PDAC). As genetic susceptibility contributes to a large proportion of chronic inflammatory intestinal diseases, we hypothesize that the genomic regions surrounding established genome-wide associated variants for these chronic inflammatory diseases are associated with PDAC. We examined the association between PDAC and genomic regions (±500 kb) surrounding established common susceptibility variants for ulcerative colitis, Crohn's disease, inflammatory bowel disease, celiac disease, chronic pancreatitis, and primary sclerosing cholangitis. We analyzed summary statistics from genome-wide association studies data for 8,384 cases and 11,955 controls of European descent from two large consortium studies using the summary data-based adaptive rank truncated product method to examine the overall association of combined genomic regions for each inflammatory disease group. Combined genomic susceptibility regions for ulcerative colitis, Crohn disease, inflammatory bowel disease, and chronic pancreatitis were associated with PDAC at P values < 0.05 (0.0040, 0.0057, 0.011, and 3.4 × 10-6, respectively). After excluding the 20 PDAC susceptibility regions (±500 kb) previously identified by GWAS, the genomic regions for ulcerative colitis, Crohn disease, and inflammatory bowel disease remained associated with PDAC (P = 0.0029, 0.0057, and 0.0098, respectively). Genomic regions for celiac disease (P = 0.22) and primary sclerosing cholangitis (P = 0.078) were not associated with PDAC. Our results support the hypothesis that genomic regions surrounding variants associated with inflammatory intestinal diseases, particularly, ulcerative colitis, Crohn disease, inflammatory bowel disease, and chronic pancreatitis are associated with PDAC. SIGNIFICANCE: The joint effects of common variants in genomic regions containing susceptibility loci for inflammatory bowel disease and chronic pancreatitis are associated with PDAC and may provide insights to understanding pancreatic cancer etiology.

Survival outcomes and risk group validation from SWOG S0925: a randomized phase II study of cixutumumab in new metastatic hormone-sensitive prostate cancer

BACKGROUND

Cixutumumab, a monoclonal antibody targeting insulin-like growth factor I receptor, did not improve undetectable prostate-specific antigen (PSA) rate at 28 weeks when combined with androgen deprivation in the randomized phase II SWOG S0925 trial for patients with new metastatic hormone-sensitive prostate cancer. We now present mature survival analyses, along with pre-specified secondary and exploratory endpoints.

METHODS

We randomized 210 patients to androgen deprivation with or without cixutumumab, 105 per treatment arm. We used Kaplan-Meier curves to analyze overall survival, radiographic progression-free survival, and castration resistance-free survival by treatment arm, disease volume, and risk group. We explored differences in survival by treatment arm via covariate-adjusted Cox proportional hazards models adjusted for disease volume and risk.

RESULTS

No difference was seen between treatment arms in overall survival (HR 1.01 [0.70-1.45]; p = 0.97), radiographic progression-free survival (HR 1.17 [0.85-1.60]; p = 0.35), or castration resistance-free survival (HR 1.02 [0.75-1.41]; p = 0.88). At baseline, 105/198 (53.0%) patients had high-risk features and 119/210 (56.7%) had high-volume disease; 16.7% of patients had discordant classifications of high or low category for risk and volume. Adjusting for risk or volume yielded no differences in overall survival between arms. Inferior survival was observed in high-risk (HR 1.89 [1.29-2.80]; p = 0.001) and high-volume (HR 2.75 [1.84-4.10]; p < 0.0001) disease. Disease volume was a better fit to survival data than risk group (AIC 878.3 vs. 889.2). Compared to patients achieving undetectable PSA at 28 weeks, inferior survival was observed in patients whose PSA was >0.2 to ≤4.0 ng/mL (HR 3.72 [1.99-6.95]; p < 0.0001) or >4.0 ng/mL (HR 7.13 [4.24-11.9]; p < 0.0001).

CONCLUSIONS

In new metastatic hormone-sensitive prostate cancer, addition of cixutumumab to androgen deprivation did not improve survival. Baseline risk and disease volume carried prognostic value for this distinct trial population, although disease volume added more prognostic information. PSA treatment response was a strong intermediate endpoint for survival.

Genome-Wide Gene-Diabetes and Gene-Obesity Interaction Scan in 8,255 Cases and 11,900 Controls from PanScan and PanC4 Consortia

BACKGROUND

Obesity and diabetes are major modifiable risk factors for pancreatic cancer. Interactions between genetic variants and diabetes/obesity have not previously been comprehensively investigated in pancreatic cancer at the genome-wide level.

METHODS

We conducted a gene-environment interaction (GxE) analysis including 8,255 cases and 11,900 controls from four pancreatic cancer genome-wide association study (GWAS) datasets (Pancreatic Cancer Cohort Consortium I-III and Pancreatic Cancer Case Control Consortium). Obesity (body mass index ≥30 kg/m2) and diabetes (duration ≥3 years) were the environmental variables of interest. Approximately 870,000 SNPs (minor allele frequency ≥0.005, genotyped in at least one dataset) were analyzed. Case-control (CC), case-only (CO), and joint-effect test methods were used for SNP-level GxE analysis. As a complementary approach, gene-based GxE analysis was also performed. Age, sex, study site, and principal components accounting for population substructure were included as covariates. Meta-analysis was applied to combine individual GWAS summary statistics.

RESULTS

No genome-wide significant interactions (departures from a log-additive odds model) with diabetes or obesity were detected at the SNP level by the CC or CO approaches. The joint-effect test detected numerous genome-wide significant GxE signals in the GWAS main effects top hit regions, but the significance diminished after adjusting for the GWAS top hits. In the gene-based analysis, a significant interaction of diabetes with variants in the FAM63A (family with sequence similarity 63 member A) gene (significance threshold P < 1.25 × 10-6) was observed in the meta-analysis (P GxE = 1.2 ×10-6, P Joint = 4.2 ×10-7).

CONCLUSIONS

This analysis did not find significant GxE interactions at the SNP level but found one significant interaction with diabetes at the gene level. A larger sample size might unveil additional genetic factors via GxE scans.

IMPACT

This study may contribute to discovering the mechanism of diabetes-associated pancreatic cancer.

A Germline Variant at 8q24 Contributes to Familial Clustering of Prostate Cancer in Men of African Ancestry

Although men of African ancestry have a high risk of prostate cancer (PCa), no genes or mutations have been identified that contribute to familial clustering of PCa in this population. We investigated whether the African ancestry-specific PCa risk variant at 8q24, rs72725854, is enriched in men with a PCa family history in 9052 cases, 143 cases from high-risk families, and 8595 controls of African ancestry. We found the risk allele to be significantly associated with earlier age at diagnosis, more aggressive disease, and enriched in men with a PCa family history (32% of high-risk familial cases carried the variant vs 23% of cases without a family history and 12% of controls). For cases with two or more first-degree relatives with PCa who had at least one family member diagnosed at age <60 yr, the odds ratios for TA heterozygotes and TT homozygotes were 3.92 (95% confidence interval [CI] = 2.13-7.22) and 33.41 (95% CI = 10.86-102.84), respectively. Among men with a PCa family history, the absolute risk by age 60 yr reached 21% (95% CI = 17-25%) for TA heterozygotes and 38% (95% CI = 13-65%) for TT homozygotes. We estimate that in men of African ancestry, rs72725854 accounts for 32% of the total familial risk explained by all known PCa risk variants. PATIENT SUMMARY: We found that rs72725854, an African ancestry-specific risk variant, is more common in men with a family history of prostate cancer and in those diagnosed with prostate cancer at younger ages. Men of African ancestry may benefit from the knowledge of their carrier status for this genetic risk variant to guide decisions about prostate cancer screening.

Abstract 3517: A germline variant at 8q24 contributes to familial clustering of prostate cancer in men of African ancestry

Germline variation at 8q24 is the strongest risk factor for prostate cancer (PCa) across all racial and ethnic populations. While most 8q24 associations have been observed across populations, rs72725854 [T risk allele frequency ~6%] is only found in men of African ancestry and is the strongest known genome-wide association signal for PCa in this population. We investigated whether the T allele of rs72725854 is associated with PCa family history and age at diagnosis, characteristics known to have a strong genetic component. Analyses were performed using a sample of 9,052 cases and 8,595 controls from the African Ancestry Prostate Cancer (AAPC) GWAS Consortium and the ELLIPSE/PRACTICAL OncoArray Consortium. Participants were unselected for PCa family history. Among cases, 23.7% carried at least one copy of the T allele versus 11.6% of controls. The OR was 2.29 (95% CI=2.10–2.49) for TA heterozygotes and 5.04 (95% CI=3.36–7.55) for TT homozygotes. The percentage of cases carrying the T allele was significantly greater for men with a PCa family history (27.4% vs. 22.7% without a family history, p=0.002) and for men diagnosed &lt;60 (28.2% vs. 21.6% if over ≥60, p=0.002). The mean age at diagnosis for men with the TT genotype was 61.1 years (sd=8.7), compared to 62.7 (sd=9.1) for TA heterozygotes and 64.3 (sd=8.9) for AA homozygotes (p=5.7E-14). Carrier frequency was highest among men with both a positive family history and an early diagnosis (30.8%). The T allele was also over-represented in cases with more advanced PCa, with carrier frequencies ranging from 26% for lethal PCa (metastatic disease, PSA&gt;100 ng/ml or death from PCa), 25.4% for high-risk disease (stage T3/T4, Gleason 8-10, or PSA=20-100 ng/ml), 24.6% for intermediate-risk disease (Gleason=7, stage T1/T2, and PSA=10-20 ng/ml), and 21.4% for low-risk disease (Gleason&lt;7, stage T1/T2, and PSA&lt;10 ng/ml) (p=0.026). We also examined whether the risk allele is over-represented in 144 men from PCa families, with multiple first- and/or second-degree relatives with PCa or men diagnosed with PCa ≤55 years old. Among affected probands, 32.7% carried the risk allele, with 3.5% being homozygous carriers. The OR for TA heterozygotes and TT homozygotes was 3.41 (95% CI=2.33–4.98) and 11.06 (95% CI=3.92–31.18), respectively. Among men without a family history, the absolute risk for PCa by age 60 for non-risk allele carriers was 4.3%, compared to 9.0% and 15.6% for TA heterozygotes and TT homozygotes, respectively. Absolute risks by age 60 were higher among men with a family history of prostate cancer, reaching 9.0% for non-risk allele carriers, compared to 20.8% and 37.7% for TA heterozygotes and TT homozygotes, respectively. Given the high PCa risk conveyed by rs72725854 and the greater frequency of the allele in men with more aggressive and lethal disease, carriers of the risk allele would benefit from earlier and more regular PSA screening.

Citation Format: Burcu F. Darst, Jeannette T. Bensen, Sue A. Ingles, Benjamin A. Rybicki, Barbara Nemesure, Esther M. John, Jay H. Fowke, Victoria L. Stevens, Sonja I. Berndt, Chad D. Huff, Jong Y. Park, Wei Zheng, Elaine A. Ostrander, Shiv Srivastava, John Carpten, Thomas A. Sellers, Maureen Sanderson, Dana C. Crawford, Olivier Cussenot, Jennifer Cullen, Rick A. Kittles, Jianfeng Xu, Zsofia Kote-Jarai, Luc Multigner, Marie-Elise Parent, Florence Menegaux, Geraldine Cancel-Tassin, Adam S. Kibel, Eric A. Klein, Phyllis J. Goodman, Jennifer J. Hu, Graham Casey, Anselm J. Hennis, Ian M. Thompson, Robin Leach, James L. Mohler, Elizabeth T. Fontham, Gary J. Smith, Jack A. Taylor, Rosalind A. Eeles, Laurent Brureau, Stephen J. Chanock, Stephen Watya, Janet L. Stanford, Diptasri Mandal, William B. Isaacs, Kathleen A. Cooney, William J. Blot, David V. Conti, Christopher A. Haiman. A germline variant at 8q24 contributes to familial clustering of prostate cancer in men of African ancestry [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3517.

The association between serum sex steroid hormone concentrations and intraprostatic inflammation in men without prostate cancer and irrespective of clinical indication for biopsy in the placebo arm of the Prostate Cancer Prevention Trial

BACKGROUND

Intraprostatic inflammation is an emerging prostate cancer risk factor. Estrogens are pro-inflammatory while androgens are anti-inflammatory. Thus, we investigated whether serum sex steroid hormone concentrations are associated with intraprostatic inflammation to inform mechanistic links among hormones, inflammation, and prostate cancer.

METHODS

We conducted a cross-sectional study among 247 men in the placebo arm of the Prostate Cancer Prevention Trial who had a negative end-of-study biopsy, most (92.7%) performed without clinical indication per trial protocol. Serum estradiol, estrone, and testosterone were previously measured by immunoassay in pooled baseline and Year 3 serum. Free estradiol and free testosterone were calculated. Inflammation was visually assessed (median of three prostate biopsy cores per man). Polytomous or logistic regression was used to estimate the odds ratio (OR) and 95% confidence interval (CI) of some or all cores inflamed (both vs none) or any core inflamed (vs none) by hormone tertile, adjusting for age, race, and family history. We evaluated effect modification by waist circumference and body mass index (BMI).

RESULTS

In all, 51.4% had some and 26.3% had all cores inflamed. Free (P-trend = .11) but not total estradiol was suggestively inversely associated with all cores inflamed. In men with waist circumference greater than or equal to 102 cm (P-trend = .021) and BMI ≥ 27.09 kg/m² (P-trend = .0037) free estradiol was inversely associated with any core inflamed. Estrone was inversely associated with all cores inflamed (T3: OR = 0.36, 95% CI 0.14-0.95, P-trend = .036). Total (T3: OR = 1.91, 95% CI 0.91-4.02, P-trend = .11) and free (T3: OR = 2.19, 95% CI 1.01-4.74, P-trend = .05) testosterone were positively associated with any core inflamed, especially free testosterone in men with waist circumference less than 102 cm (T3: OR = 3.51, 95% CI 1.03-12.11, P-trend = .05).

CONCLUSIONS

In this first study in men without prostate cancer and irrespective of clinical indication for biopsy, contrary to the hypothesis, circulating estrogens appeared to be inversely associated, especially in heavy men, whereas androgens appeared to be positively associated with intraprostatic inflammation.

A comparison of general, genitourinary, bowel, and sexual quality of life among long term survivors of prostate, bladder, colorectal, and lung cancer

OBJECTIVES

Studies of local stage prostate cancer survivors suggest that treatments carry risk of persistent impotence, incontinence, and bowel dysfunction. To examine impacts of cancer type and side effects on health-related quality of life (HRQoL) in long-term cancer survivorship, we evaluated 5-year follow-up of patients with prostate cancer and compared results with a matched group of male long-term survivors of other local-stage cancers.

MATERIALS AND METHODS

We examined genitourinary, bowel and sexual symptoms, and general quality of life. Matched survivors of colorectal, lung, and bladder cancers were recruited via registries in 3 different regions in the United States. Patients were surveyed 3-5 years after diagnosis with the SF-12 and EPIC to evaluate general mental and physical health-related quality of life (HRQoL) and patient function and bother.

RESULTS

We analyzed responses from long-term prostate (n = 77) and bladder, colorectal, and lung cancer (n = 124) patients. In multivariate analysis, long-term local stage prostate cancer survivors had significantly higher SF-12 physical component scores but did not differ from long-term survivors of other cancers in terms of their SF-12 mental summary scores. Prostate survivors had similar mental, urinary, bowel, and sexual HRQoL compared to long-term survivors of other local stage cancers.

CONCLUSION

Long-term general and prostate-specific HRQoL was similar between local stage prostate and bladder, colorectal, and lung patients with cancer. Future research focusing on factors other than initial treatment and the cancer type per se may provide more meaningful information regarding factors that predict disparities on HRQoL among longer-term survivors of early stage male cancers.

Use of Aspirin and Statins in Relation to Inflammation in Benign Prostate Tissue in the Placebo Arm of the Prostate Cancer Prevention Trial

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.

17-Gene Genomic Prostate Score Test Results in the Canary Prostate Active Surveillance Study (PASS) Cohort

PURPOSE

The 17-gene Oncotype DX Genomic Prostate Score (GPS) test predicts adverse pathology (AP) in patients with low-risk prostate cancer treated with immediate surgery. We evaluated the GPS test as a predictor of outcomes in a multicenter active surveillance cohort.

MATERIALS AND METHODS

Diagnostic biopsy tissue was obtained from men enrolled at 8 sites in the Canary Prostate Active Surveillance Study. The primary endpoint was AP (Gleason Grade Group [GG] ≥ 3, ≥ pT3a) in men who underwent radical prostatectomy (RP) after initial surveillance. Multivariable regression models for interval-censored data were used to evaluate the association between AP and GPS. Inverse probability of censoring weighting was applied to adjust for informative censoring. Predictiveness curves were used to evaluate how models stratified risk of AP. Association between GPS and time to upgrade on surveillance biopsy was evaluated using Cox proportional hazards models.

RESULTS

GPS results were obtained for 432 men (median follow-up, 4.6 years); 101 underwent RP after a median 2.1 years of surveillance, and 52 had AP. A total of 167 men (39%) upgraded at a subsequent biopsy. GPS was significantly associated with AP when adjusted for diagnostic GG (hazards ratio [HR]/5 GPS units, 1.18; 95% CI, 1.04 to 1.44; P = .030), but not when also adjusted for prostate-specific antigen density (PSAD; HR, 1.85; 95% CI, 0.99 to 4.19; P = .066). Models containing PSAD and GG, or PSAD, GG, and GPS may stratify risk better than a model with GPS and GG. No association was observed between GPS and subsequent biopsy upgrade (P = .48).

CONCLUSION

In our study, the independent association of GPS with AP after initial active surveillance was not statistically significant, and there was no association with upgrading in surveillance biopsy. Adding GPS to a model containing PSAD and diagnostic GG did not significantly improve stratification of risk for AP over the clinical variables alone.

Comparative Survival of Asian and White Metastatic Castration-Resistant Prostate Cancer Men Treated With Docetaxel

There are few data regarding disparities in overall survival (OS) between Asian and white men with metastatic castration-resistant prostate cancer (mCRPC). We compared OS of Asian and white mCRPC men treated in phase III clinical trials with docetaxel and prednisone (DP) or a DP-containing regimen. Individual participant data from 8820 men with mCRPC randomly assigned on nine phase III trials to receive DP or a DP-containing regimen were combined. Men enrolled in these trials had a diagnosis of prostate adenocarcinoma. The median overall survival was 18.8 months (95% confidence interval [CI] = 17.4 to 22.1 months) and 21.2 months (95% CI = 20.8 to 21.7 months) for Asian and white men, respectively. The pooled hazard ratio for death for Asian men compared with white men, adjusted for baseline prognostic factors, was 0.95 (95% CI = 0.84 to 1.09), indicating that Asian men were not at increased risk of death. This large analysis showed that Asian men did not have shorter OS duration than white men treated with docetaxel.

Clinical outcomes in men of diverse ethnic backgrounds with metastatic castration-resistant prostate cancer

BACKGROUND

We have shown previously in multivariable analysis that black men had 19% lower risk of death than white men with metastatic castration-resistant prostate cancer (mCRPC) treated with a docetaxel and prednisone (DP)-based regimen. The primary goal of this analysis was to compare progression-free survival (PFS), biochemical PFS, ≥50% decline in prostate-specific antigen (PSA) from baseline and objective response rate (ORR) in white, black and Asian men with mCRPC treated with a DP-based regimen.

PATIENTS AND METHODS

Individual patient data from 8820 mCRPC men randomized on nine phase III trials to a DP-containing regimen were combined. Race used in the analysis was based on self-report. End points were PFS, biochemical PSA, ≥50% decline in PSA from baseline and ORR. The proportional hazards and the logistic regression models were employed to assess the prognostic importance of race in predicting outcomes adjusting for established prognostic factors.

RESULTS

Of 8820 patients, 7528 (85%) were white, 500 (6%) were black, 424 were Asian (5%) and 368 (4%) had race unspecified. Median PFS were 8.3 [95% confidence interval (CI) 8.2-8.5], 8.2 (95% CI 7.4-8.8) and 8.3 (95% CI 7.6-8.8) months in white, black and Asian men, respectively. Median PSA PFS were 9.9 (95% CI 9.7-10.4), 8.5 (95% CI 8.0-10.3) and 11.1 (95% CI 9.9-12.5) months in white, black and Asian men, respectively.

CONCLUSIONS

We observed no differences in clinical outcomes by race and ethnic groups in men with mCRPC enrolled on these phase III clinical trials with DP.

Vitamin D Pathway and Other Related Polymorphisms and Risk of Prostate Cancer: Results from the Prostate Cancer Prevention Trial

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; P _interaction < 0.05), GC/rs222014 (finasteride OR = 1.36, placebo OR = 0.85; P _interaction < 0.05), and CYP27B1/rs703842 (finasteride OR = 0.76, placebo OR = 1.10; P _interaction < 0.05) among Caucasians, and C10orf88/rs6599638 (finasteride OR = 4.68, placebo OR = 1.39; P _interaction < 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; P _interaction < 0.05 and finasteride OR = 0.70, placebo OR = 1.28; P _interaction < 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.

Vortioxetine reverses medial prefrontal cortex-mediated cognitive deficits in male rats induced by castration as a model of androgen deprivation therapy for prostate cancer

RATIONALE

Androgen deprivation therapy (ADT) is an effective treatment for prostate cancer, but induces profound cognitive impairment. Little research has addressed mechanisms underlying these deficits or potential treatments. This is an unmet need to improve quality of life for prostate cancer survivors.

OBJECTIVES

We investigated mechanisms of cognitive impairment after ADT in rats and potential utility of the multimodal serotonin-targeting drug, vortioxetine, to improve the impairment, as vortioxetine has specific efficacy against cognitive impairment in depression.

METHODS

Male Sprague-Dawley rats were surgically castrated. Vortioxetine (28 mg/kg/day) was administered in the diet. The attentional set-shifting test was used to assess medial prefrontal cortex (mPFC) executive function. Afferent-evoked field potentials were recorded in the mPFC of anesthetized rats after stimulating the ventral hippocampus (vHipp) or medial dorsal thalamus (MDT). Gene expression changes were assessed by microarray. Effects of vortioxetine on growth of prostate cancer cells were assessed in vitro.

RESULTS

ADT impaired cognitive set shifting and attenuated responses evoked in the mPFC by the vHipp afferent, but not the MDT. Both the cognitive impairment and attenuated vHipp-evoked responses were reversed by chronic vortioxetine treatment. Preliminary investigation of gene expression in the mPFC indicates that factors involved in neuronal plasticity and synaptic transmission were down-regulated by castration and up-regulated by vortioxetine in castrated animals. Vortioxetine neither altered the growth of prostate cancer cells in vitro nor interfered with the antiproliferative effects of the androgen antagonist, enzalutamide.

CONCLUSIONS

These results suggest that vortioxetine may be useful in mitigating cognitive impairment associated with ADT for prostate cancer.

Variations in prostate biopsy recommendation and acceptance confound evaluation of risk factors for prostate cancer: Examining race and BMI

BACKGROUND

Prostate cancer is ubiquitous in older men; differential screening patterns and variations in biopsy recommendations and acceptance will affect which man is diagnosed and, therefore, evaluation of cancer risk factors. We describe a statistical method to reduce prostate cancer detection bias among African American (n = 3398) and Non-Hispanic White men (n = 22,673) who participated in the Selenium and Vitamin E Cancer Prevention trial (SELECT) and revisit a previously reported association between race, obesity and prostate cancer risk.

METHODS

For men with screening values suggesting prostate cancer but in whom biopsy was not performed, the Prostate Cancer Prevention Trial Risk Calculator was used to estimate probability of prostate cancer. Associations of body mass index (BMI) and race with incident prostate cancer were compared for observed versus imputation-enhanced outcomes using incident density ratios.

RESULTS

Accounting for differential biopsy assessment, the previously reported positive linear trend between BMI and prostate cancer in African American men was not observed; no BMI association was found among Non-Hispanic White men.

CONCLUSIONS

Differential disease classification among men who may be recommended to undergo and then consider whether to accept a prostate biopsy leads to inaccurate identification of prostate cancer risk factors. Imputing a man's prostate cancer status reduces detection bias. Covariate adjustment does not address the problem of outcome misclassification. Cohorts evaluating incident prostate cancer should collect longitudinal screening and biopsy data to adjust for this potential bias.

Using Medicare Claims to Examine Long-term Prostate Cancer Risk of Finasteride in the Prostate Cancer Prevention Trial

Background

Investigators have used administrative claims to better understand cancer outcomes when a research question cannot feasibly be examined within a study. The Prostate Cancer Prevention Trial (PCPT) showed that seven years of finasteride reduced prostate cancer (PC) risk by 25% in men age 55 years or older. However, it was unclear whether the observed reduction in PC for finasteride participants would be maintained after finasteride discontinuation.

Methods

We examined PC diagnoses identified by PCPT study records and Medicare claims (finasteride = 9423, placebo = 9457). A Medicare-defined PC diagnosis algorithm was defined using diagnosis and procedure codes. Multivariable Cox regression was used to examine time to PC within prespecified follow-up windows (<6.5, 6.5-7.5, and >7.5 years) using time-dependent covariates interacting with intervention assignment to account for the PCPT protocol-specified end-of-study biopsy at seven years. All statistical tests were two-sided.

Results

Median follow-up using the linked database was 16 years. Overall, finasteride arm participants had a 21.1% decrease in the hazard ratio of PC (hazard ratio [HR] = 0.79, 95% confidence interval [CI] = 0.74 to 0.84, P < .001). The beneficial effect of finasteride in reducing the hazard ratio of PC was most pronounced in the first 7.5 years (HR = 0.71, 95% CI = 0.66 to 0.77, P < .001), consistent with the original study findings; after 7.5 years, there was no increased risk of PC for finasteride arm participants (HR = 1.10, 95% CI = 0.96 to 1.26, P = .18).

Conclusions

Finasteride provides a substantial reduction in PC through 16 years of follow-up. There was no strong evidence that the benefit of finasteride diminished after the end-of-study follow-up. Utilizing Medicare claims to augment PCPT follow-up illustrates how the novel use of secondary data sources can enhance the ability to detect long-term outcomes from prospective studies.