Impact of Family History and Germline Genetic Risk Single Nucleotide Polymorphisms on Long-Term Outcomes of Favorable-Risk Prostate Cancer

PURPOSE

Family history and germline genetic risk single nucleotide polymorphisms (SNPs) have been separately shown to stratify lifetime risk of prostate cancer. Here, we evaluate the combined prognostic value of family history of prostate and other related cancers and germline risk SNPs among patients with favorable-risk prostate cancer.

MATERIALS AND METHODS

A total of 1367 participants from the prospective Health Professionals Follow-up Study diagnosed with low- or favorable intermediate-risk prostate cancer from 1986 to 2017 underwent genome-wide SNP genotyping. Multivariable Cox regression was used to estimate the association between family history, specific germline risk variants, and a 269 SNP polygenic risk score with prostate cancer‒specific death.

RESULTS

Family history of prostate, breast, and/or pancreatic cancer was observed in 489 (36%) participants. With median follow-up from diagnosis of 14.9 years, participants with favorable-risk prostate cancer with a positive family history had a significantly higher risk of prostate cancer‒specific death (HR 1.95, 95% CI 1.15-3.32, P = .014) compared to those without any family history. The rs2735839 (19q13) risk allele was associated with prostate cancer‒specific death (HR 1.81 per risk allele, 95% CI 1.04-3.17, P = .037), whereas the polygenic risk score was not. Combined family history and rs2735839 risk allele were each associated with an additive risk of prostate cancer‒specific death (HR 1.78 per risk factor, 95% CI 1.25-2.53, P = .001).

CONCLUSIONS

Family history of prostate, breast, or pancreatic cancer and/or a 19q13 germline risk allele are associated with an elevated risk of prostate cancer‒specific death among favorable-risk patients. These findings have implications for how family history and germline genetic risk SNPs should be factored into clinical decision-making around favorable-risk prostate cancer.

Healthy dietary patterns and risk of prostate cancer in men at high genetic risk

Prostate cancer has high heritability. Healthy lifestyle has been associated with lower lethal prostate cancer risk among men at increased genetic susceptibility, but the role of healthy dietary patterns remains unknown. We prospectively followed 10,269 genotyped men in the Health Professionals Follow-up Study (1993-2019). Genetic risk was quantified using an established polygenic risk score (PRS). Five dietary patterns were investigated: healthy eating index, Mediterranean, diabetes risk-reducing, hyperinsulinemic and inflammatory diet. Overall and lethal prostate cancer rates (metastatic disease/prostate cancer-specific death) were analyzed using multivariable Cox proportional hazards models. During 26 years of follow-up, 2133 overall and 253 lethal prostate cancer events were documented. In the highest PRS quartile, higher adherence to a diabetes risk-reducing diet was associated with lower rates of overall (top vs. bottom quintile HR [95% CI], 0.74 [0.58-0.94]) and lethal prostate cancer (0.43 [0.21-0.88]). A low insulinemic diet was associated with similar lower rates (overall, 0.76 [0.60-0.95]; lethal, 0.46 [0.23-0.94]). Other dietary patterns showed weaker, but similar associations. In the highest PRS quartile, men with healthy lifestyles based on body weight, physical activity, and low insulinemic diet had a substantially lower rate (0.26 [0.13-0.49]) of lethal prostate cancer compared with men with unhealthy lifestyles, translating to a lifetime risk of 3.4% (95% CI, 2.3%-5.0%) among those with healthy lifestyles and 9.5% (5.3%-16.7%) among those with unhealthy lifestyles. Our findings indicate that lifestyle modifications lowering insulin resistance and chronic hyperinsulinemia could be relevant in preventing aggressive prostate cancer among men genetically predisposed to prostate cancer.

Combining magnetic resonance imaging with a multi-ancestry polygenic risk score to improve identification of clinically significant prostate cancer

Multi-parametric magnetic resonance imaging (mpMRI) has emerged as an important tool for identifying clinically significant prostate cancer. We examined if the addition of a 400-variant multi-ancestry polygenic risk score (PRS) to mpMRI has the potential to improve identification. Based on data from 24 617 men from the Mass General Brigham Biobank, we identified 1243 men who underwent mpMRI. Men in the top PRS quartile were more likely to have clinically significant prostate cancer (47.1% vs 28.6% in the bottom PRS quartile, adjusted relative proportion 1.72 [95% CI = 1.35 to 2.19]). Both among men with a positive and a negative mpMRI, men in the top PRS quartile had the highest frequency of clinically significant cancer. In a constructed scenario for selecting men to undergo biopsy, use of the PRS lowered the frequency of missed clinically significant cancers from 9.1% to 5.9%. Our study provides initial support for using the PRS to improve identification of potentially lethal prostate cancer.

SLCO1B3 and SLCO2B1 genotypes, androgen deprivation therapy, and prostate cancer outcomes: a prospective cohort study and meta-analysis

Solute carrier organic anion (SLCO) transporters (OATP transporters) are involved in cellular uptake of drugs and hormones. Germline variants in SLCO1B3 and SLCO2B1 have been implicated in prostate cancer progression and therapy response, including to androgen deprivation and statin medications, but results have appeared heterogeneous. We conducted a cohort study of five single-nucleotide polymorphisms (SNPs) in SLCO1B3 and SLCO2B1 with prior evidence among 3208 men with prostate cancer who participated in the Health Professionals Follow-up Study or the Physicians' Health Study, following participants prospectively after diagnosis over 32 years (median, 14 years) for development of metastases and cancer-specific death (lethal disease, 382 events). Results were suggestive of, but not conclusive for, associations between some SNPs and lethal disease and differences by androgen deprivation and statin use. All candidate SNPs were associated with SLCO mRNA expression in tumor-adjacent prostate tissue. We also conducted a systematic review and harmonized estimates for a dose-response meta-analysis of all available data, including 9 further studies, for a total of 5598 patients and 1473 clinical events. The A allele of the exonic SNP rs12422149 (14% prevalence), which leads to lower cellular testosterone precursor uptake via SLCO2B1, was associated with lower rates of prostate cancer progression (hazard ratio per A allele, 0.80; 95% confidence interval, 0.69-0.93), with little heterogeneity between studies (I2, 0.27). Collectively, the totality of evidence suggests a strong association between inherited genetic variation in SLCO2B1 and prostate cancer prognosis, with potential clinical use in risk stratification related to androgen deprivation therapy.

Characterizing prostate cancer risk through multi-ancestry genome-wide discovery of 187 novel risk variants

The transferability and clinical value of genetic risk scores (GRSs) across populations remain limited due to an imbalance in genetic studies across ancestrally diverse populations. Here we conducted a multi-ancestry genome-wide association study of 156,319 prostate cancer cases and 788,443 controls of European, African, Asian and Hispanic men, reflecting a 57% increase in the number of non-European cases over previous prostate cancer genome-wide association studies. We identified 187 novel risk variants for prostate cancer, increasing the total number of risk variants to 451. An externally replicated multi-ancestry GRS was associated with risk that ranged from 1.8 (per standard deviation) in African ancestry men to 2.2 in European ancestry men. The GRS was associated with a greater risk of aggressive versus non-aggressive disease in men of African ancestry (P = 0.03). Our study presents novel prostate cancer susceptibility loci and a GRS with effective risk stratification across ancestry groups.

Food Insecurity Is Associated With Dysfunctional Eating Behaviors Among Adults in Puerto Rico

OBJECTIVE

To examine the association between food insecurity and dysfunctional eating behaviors among adults in Puerto Rico.

METHODS

Data from 865 participants were obtained from baseline interviews from the Puerto Rico Observational Study of Psychosocial, Environmental, and Chronic Disease Trends (PROSPECT) cohort. The association between food insecurity and emotional eating (EE) and uncontrolled eating (UE) (categorized as no/moderate/high) was examined using multinomial logistic models. Potential mediation by perceived stress was explored.

RESULTS

The prevalence of food insecurity was 20.3%. Compared with adults with food security, adults with food insecurity had higher odds of both moderate EE (odds ratio [OR], 1.91; 95% confidence interval [CI], 1.18-3.09) and high EE (OR, 2.85; 95% CI, 1.75-4.64), and both moderate UE (OR, 1.78; 95% CI, 0.91-3.50) and high UE (OR, 3.28; 95% CI, 1.70-6.33). Perceived stress slightly attenuated these associations.

CONCLUSIONS AND IMPLICATIONS

Food insecurity was associated with a higher likelihood of engaging in dysfunctional eating behaviors. Interventions alleviating food insecurity or stress might help adults sustain healthy eating behaviors.

Agent Orange exposure and prostate cancer risk in the Million Veteran Program

Purpose

Exposure to Agent Orange, a known carcinogen, might increase risk of prostate cancer (PCa). We sought to investigate the association of Agent Orange exposure and PCa risk when accounting for race/ethnicity, family history, and genetic risk in a diverse population of US Vietnam War veterans.

Methods & Materials

This study utilized the Million Veteran Program (MVP), a national, population-based cohort study of United States military veterans conducted 2011-2021 with 590,750 male participants available for analysis. Agent Orange exposure was obtained using records from the Department of Veterans Affairs (VA) using the US government definition of Agent Orange exposure: active service in Vietnam while Agent Orange was in use. Only veterans who were on active duty (anywhere in the world) during the Vietnam War were included in this analysis (211,180 participants). Genetic risk was assessed via a previously validated polygenic hazard score calculated from genotype data. Age at diagnosis of any PCa, diagnosis of metastatic PCa, and death from PCa were assessed via Cox proportional hazards models.

Results

Exposure to Agent Orange was associated with increased PCa diagnosis (HR 1.04, 95% CI 1.01-1.06, p=0.003), primarily among Non-Hispanic White men (HR 1.09, 95% CI 1.06- 1.12, p<0.001). When accounting for race/ethnicity and family history, Agent Orange exposure remained an independent risk factor for PCa diagnosis (HR 1.06, 95% CI 1.04-1.09, p<0.05). Univariable associations of Agent Orange exposure with PCa metastasis (HR 1.08, 95% CI 0.99-1.17) and PCa death (HR 1.02, 95% CI 0.84-1.22) did not reach significance on multivariable analysis. Similar results were found when accounting for polygenic hazard score.

Conclusions

Among US Vietnam War veterans, Agent Orange exposure is an independent risk factor for PCa diagnosis, though associations with PCa metastasis or death are unclear when accounting for race/ethnicity, family history, and/or polygenic risk.

The Imperative for Population-based Cancer Registration of All Metastatic Cancers

Metastases are the main cause of morbidity and mortality from solid tumors. Surprisingly, population-based cancer registries in various countries, including the National Cancer Institute's Surveillance, Epidemiology, and End Results program in the United States, only capture data on individuals diagnosed with cancers that are metastatic at diagnosis (M1). Metastatic recurrences of previously diagnosed, initially nonmetastatic tumors are missed. Devasia and colleagues specify an illness-death model for chronic disease and estimate that in prostate cancer, which has a large pool of primary disease that may or may not progress to metastases, about half of all metastatic cancers arise as recurrences from initially nonmetastatic disease. Capturing all incident metastatic cancer cases across all tumor types in population-based cancer registries, not only based on initial stage at diagnosis, would be critical to better understand the disparities in metastatic disease burden and the effectiveness of primary prevention, screening, and therapies for primary and metastatic disease. See related article by Devasia et al., p. 659.

A Healthy Lifestyle in Men at Increased Genetic Risk for Prostate Cancer

BACKGROUND

Prostate cancer is the most heritable cancer. There is a need to identify possible modifiable factors for men at an increased risk of prostate cancer due to genetic factors.

OBJECTIVE

To examine whether men at an increased genetic risk of prostate cancer can offset their risk of disease or disease progression by adhering to a healthy lifestyle.

DESIGN, SETTING, AND PARTICIPANTS

We prospectively followed 12 411 genotyped men in the Health Professionals Follow-up Study (1993-2019) and the Physicians' Health Study (1983-2010). Genetic risk of prostate cancer was quantified using a polygenic risk score (PRS). A healthy lifestyle was defined by healthy weight, vigorous physical activity, not smoking, and a healthy diet.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Overall and lethal prostate cancer events (metastatic disease/prostate cancer-specific death) were analyzed using time-to-event analyses estimating hazard ratios (HRs) and lifetime risks.

RESULTS AND LIMITATIONS

During 27 yr of follow-up, 3005 overall prostate cancer and 435 lethal prostate cancer events were observed. The PRS enabled risk stratification not only for overall prostate cancer, but also for lethal disease with a four-fold difference between men in the highest and lowest quartiles (HR, 4.32; 95% confidence interval [CI], 3.16-5.89). Among men in the highest PRS quartile, adhering to a healthy lifestyle was associated with a decreased rate of lethal prostate cancer (HR, 0.55; 95% CI, 0.36-0.86) compared with having an unhealthy lifestyle, translating to a lifetime risk of 1.6% (95% CI, 0.8-3.1%) among the healthy and 5.3% (95% CI, 3.6-7.8%) among the unhealthy. Adhering to a healthy lifestyle was not associated with a decreased risk of overall prostate cancer.

CONCLUSIONS

Our findings suggest that a genetic predisposition for prostate cancer is not deterministic for a poor cancer outcome. Maintaining a healthy lifestyle may provide a way to offset the genetic risk of lethal prostate cancer.

PATIENT SUMMARY

This study examined whether the genetic risk of prostate cancer can be attenuated by a healthy lifestyle including a healthy weight, regular exercise, not smoking, and a healthy diet. We observed that adherence to a healthy lifestyle reduced the risk of metastatic disease and prostate cancer death among men at the highest genetic risk. We conclude that men at a high genetic risk of prostate cancer may benefit from adhering to a healthy lifestyle.

Healthy lifestyle, Agent Orange exposure, and inherited PCa risk: An analysis of the Million Veteran Program

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Background: Prostate cancer (PCa) risk is understood to be mostly unmodifiable and inherited, but there is evidence that environmental and behavioral factors may also contribute. A recent study of health professional cohorts suggests a healthy lifestyle can mitigate a high inherited risk of lethal PCa. It is unknown how modifiable factors affect PCa risk in more diverse populations. Our objective was to determine the effects of healthy lifestyle and Agent Orange exposure on PCa risk when accounting for race/ethnicity, family history, and genetic risk in a diverse population. Methods: The Million Veteran Program (MVP) is a national, population-based cohort study of United States military veterans conducted 2011-2021 with 590,750 male participants available for analysis. Healthy lifestyle was quantified as: A healthy lifestyle score (range 0-3) was calculated with a point assigned for each of the following at MVP enrollment: not a current smoker, body mass index (BMI) 30 and strenuous activity 2 days per week. Agent Orange exposure was obtained from VA records. Genetic risk was assessed via a polygenic hazard score using genotype data. Results: Healthy lifestyle was independently associated with reduced metastatic PCa (HR 0.82, 95% CI 0.77–0.87, p<0.001) and fatal PCa (HR 0.76, 95% CI 0.68–0.86, p<0.01) when accounting for family history, genetic risk, and race/ethnicity. The benefit of healthy lifestyle was also observed in Black participants on subset analysis. Agent Orange exposure was an independent factor for PCa diagnosis (HR 1.06, 95% CI 1.04-1.09). Conclusions: Adherence to a healthy lifestyle is associated with reduced risk of metastatic or fatal PCa, which offsets inherited risk.

Addition of a Genetic Risk Score for Identification of Men with a Low Prostate-specific Antigen Level in Midlife at Risk of Developing Lethal Prostate Cancer

Men with a low prostate-specific antigen (PSA) level (<1 ng/ml) in midlife may extend the rescreening interval (if aged 40-59 yr) or forgo future PSA screening (if aged >60 yr) owing to their low risk of aggressive prostate cancer (PCa). However, there is a subset of men who develop lethal PCa despite low baseline PSA. We investigated how a PCa polygenic risk score (PRS) in addition to baseline PSA impacts the prediction of lethal PCa among 483 men aged 40-70 yr from the Physicians' Health Study followed over a median of 33 yr. We examined the association of the PRS with the risk of lethal PCa (lethal cases vs controls) using logistic regression adjusted for baseline PSA. The PCa PRS was associated with risk of lethal PCa (odds ratio per 1 standard deviation in PRS [OR] 1.79, 95% confidence interval [CI] 1.28-2.49). The association between the PRS and lethal PCa was stronger for those with PSA <1 ng/ml (OR 2.23, 95% CI 1.19-4.21) than for men with PSA ≥1 ng/ml (OR 1.61, 95% CI 1.07-2.42). Our PCa PRS improved the identification of men with PSA <1 ng/ml at greater risk of future lethal PCa who should consider ongoing PSA testing.

Patient summary

A subset of men develop fatal prostate cancer despite having low prostate-specific antigen (PSA) levels in middle age. A risk score based on multiple genes can help in predicting men who may be at risk of developing lethal prostate cancer and who should be advised to have regular PSA measurements.

Differences in Prostate Cancer Transcriptomes by Age at Diagnosis: Are Primary Tumors from Older Men Inherently Different?

Older age at diagnosis is consistently associated with worse clinical outcomes in prostate cancer. We sought to characterize gene expression profiles of prostate tumor tissue by age at diagnosis. We conducted a discovery analysis in The Cancer Genome Atlas prostate cancer dataset (n = 320; 29% of men >65 years at diagnosis), using linear regressions of age at diagnosis and mRNA expression and adjusting for TMPRSS2:ERG fusion status and race. This analysis identified 13 age-related candidate genes at FDR < 0.1, six of which were also found in an analysis additionally adjusted for Gleason score. We then validated the 13 age-related genes in a transcriptome study nested in the Health Professionals Follow-up Study and Physicians' Health Study (n = 374; 53% of men >65 years). Gene expression differences by age in the 13 candidate genes were directionally consistent, and age at diagnosis was weakly associated with the 13-gene score. However, the age-related genes were not consistently associated with risk of metastases and prostate cancer-specific death. Collectively, these findings argue against tumor genomic differences as a main explanation for age-related differences in prostate cancer prognosis.

PREVENTION RELEVANCE

Older age at diagnosis is consistently associated with worse clinical outcomes in prostate cancer. This study with independent discovery and validation sets and long-term follow-up suggests that prevention of lethal prostate cancer should focus on implementing appropriate screening, staging, and treatment among older men without expecting fundamentally different tumor biology.

Family History of Prostate and Breast Cancer Integrated with a Polygenic Risk Score Identifies Men at Highest Risk of Dying from Prostate Cancer before Age 75 Years

PURPOSE

Family history of prostate cancer is one of the few universally accepted risk factors for prostate cancer. How much an assessment of inherited polygenic risk for prostate cancer adds to lifetime risk stratification beyond family history is unknown.

EXPERIMENTAL DESIGN

We followed 10,120 men in the Health Professionals Follow-up Study with existing genotype data for risk of prostate cancer and prostate cancer-specific death. We assessed to what extent family history of prostate or breast cancer, combined with a validated polygenic risk score (PRS) including 269 prostate cancer risk variants, identifies men at risk of prostate cancer and prostate cancer death across the age span.

RESULTS

During 20 years of follow-up, 1,915 prostate cancer and 166 fatal prostate cancer events were observed. Men in the top PRS quartile with a family history of prostate or breast cancer had the highest rate of both prostate cancer and prostate cancer-specific death. Compared with men at lowest genetic risk (bottom PRS quartile and no family history), the HR was 6.95 [95% confidence interval (CI), 5.57-8.66] for prostate cancer and 4.84 (95% CI, 2.59-9.03) for prostate cancer death. Men in the two upper PRS quartiles (50%-100%) or with a family history of prostate or breast cancer (61.8% of the population) accounted for 97.5% of prostate cancer deaths by age 75 years.

CONCLUSIONS

Our study shows that prostate cancer risk stratification on the basis of family history and inherited polygenic risk can identify men at highest risk of dying from prostate cancer before age 75 years.

Validation of a multi-ancestry polygenic risk score and age-specific risks of prostate cancer: A meta-analysis within diverse populations

Background

We recently developed a multi-ancestry polygenic risk score (PRS) that effectively stratifies prostate cancer risk across populations. In this study, we validated the performance of the PRS in the multi-ancestry Million Veteran Program and additional independent studies.

Methods

Within each ancestry population, the association of PRS with prostate cancer risk was evaluated separately in each case-control study and then combined in a fixed-effects inverse-variance-weighted meta-analysis. We further assessed the effect modification by age and estimated the age-specific absolute risk of prostate cancer for each ancestry population.

Results

The PRS was evaluated in 31,925 cases and 490,507 controls, including men from European (22,049 cases, 414,249 controls), African (8794 cases, 55,657 controls), and Hispanic (1082 cases, 20,601 controls) populations. Comparing men in the top decile (90-100% of the PRS) to the average 40-60% PRS category, the prostate cancer odds ratio (OR) was 3.8-fold in European ancestry men (95% CI = 3.62-3.96), 2.8-fold in African ancestry men (95% CI = 2.59-3.03), and 3.2-fold in Hispanic men (95% CI = 2.64-3.92). The PRS did not discriminate risk of aggressive versus nonaggressive prostate cancer. However, the OR diminished with advancing age (European ancestry men in the top decile: ≤55 years, OR = 7.11; 55-60 years, OR = 4.26; >70 years, OR = 2.79). Men in the top PRS decile reached 5% absolute prostate cancer risk ~10 years younger than men in the 40-60% PRS category.

Conclusions

Our findings validate the multi-ancestry PRS as an effective prostate cancer risk stratification tool across populations. A clinical study of PRS is warranted to determine whether the PRS could be used for risk-stratified screening and early detection.

Funding

This work was supported by the National Cancer Institute at the National Institutes of Health (grant numbers U19 CA214253 to C.A.H., U01 CA257328 to C.A.H., U19 CA148537 to C.A.H., R01 CA165862 to C.A.H., K99 CA246063 to B.F.D, and T32CA229110 to F.C), the Prostate Cancer Foundation (grants 21YOUN11 to B.F.D. and 20CHAS03 to C.A.H.), the Achievement Rewards for College Scientists Foundation Los Angeles Founder Chapter to B.F.D, and the Million Veteran Program-MVP017. This research has been conducted using the UK Biobank Resource under application number 42195. This research is based on data from the Million Veteran Program, Office of Research and Development, and the Veterans Health Administration. This publication does not represent the views of the Department of Veteran Affairs or the United States Government.

5-Alpha Reductase Inhibitors and Prostate Cancer Mortality among Men with Regular Access to Screening and Health Care

BACKGROUND

How 5-alpha reductase inhibitor (5-ARI) use influences prostate cancer mortality is unclear. The objective of this study was to determine whether men taking 5-ARIs with regular health care access have increased prostate cancer mortality.

METHODS

We undertook two analyses in the Health Professionals Follow-up Study examining 5-ARI use, determined by biennial questionnaires, and prostate cancer. A cohort analysis followed 38,037 cancer-free men for prostate cancer incidence from 1996 through January 2017 and mortality through January 2019. A case-only analysis followed 4,383 men with localized/locally advanced prostate cancer for mortality over a similar period. HRs and 95% confidence intervals (CI) were calculated for prostate cancer incidence and mortality.

RESULTS

Men using 5-ARIs underwent more PSA testing, prostate exams and biopsies. Over 20 years of follow-up, 509 men developed lethal disease (metastases or prostate cancer death). Among men initially free from prostate cancer, 5-ARI use was not associated with developing lethal disease [HR, 1.02; 95% confidence interval (CI), 0.71-1.46], but was associated with reduced rates of overall and localized disease (HR, 0.71; 0.60-0.83). Among men diagnosed with prostate cancer, there was no association between 5-ARI use and cancer-specific (HR, 0.78; 95% CI, 0.48-1.27) or overall survival (HR, 0.88; 95% CI, 0.72-1.07).

CONCLUSIONS

Men using 5-ARIs were less likely to be diagnosed with low-risk prostate cancer, without increasing long-term risk of lethal prostate cancer or cancer-specific death after diagnosis.

IMPACT

Our results provide evidence that 5-ARI use is safe with respect to prostate cancer mortality in the context of regular health care access. See related commentary by Hamilton, p. 1259.

Abstract 1438: Organic anion transporter(SLCO)genotype and prostate cancer progression: Prospective cohort study and meta-analysis

Background: Organic anion-transporting polypeptides, encoded by SLCO genes, have multiple substrates, including androgens. Genotype and protein levels moderate the uptake of androgens into prostate cells, a process competitively inhibited in vitro by statin medications. Single-nucleotide polymorphisms (SNPs) in SLCO2B1 influence SLCO1B2 expression and efficacy of androgen uptake in vitro.

Methods: Among men of self-reported European ancestry diagnosed with prostate cancer during prospective follow-up of the Health Professionals Follow-up Study (HPFS, diagnosed 1986-2017) and the Physicians’ Health Study (PHS, 1982-2010) combined, we evaluated four SLCO2B1 SNPs identified in prior studies and time from diagnosis to lethal disease (metastases/prostate cancer-specific death), adjusting for age, calendar year of diagnosis, and principal components of genetic variation to account for local ancestry. We also conducted a systematic review and harmonized allele coding in prior studies for a two-stage dose-response meta-analysis with additive allele coding.

Results: Of the 3208 men in the prospective cohort study, 96% were diagnosed with clinically localized (T1/T2) prostate cancer. Most were treated with radical prostatectomy (47%) or radiation (36%); 33% ever received androgen deprivation therapy (ADT). Over up to 32 years of follow-up (median, 14.4 years), 382 lethal events occurred. The intronic SNP rs1077858 had the strongest association with lethal disease (hazard ratio [HR] per minor allele 1.14, 95% confidence interval [CI] 0.98-1.33). Data were suggestive of potential differences for the four SNPs by use of statins and ADT but were not conclusive. The systematic review identified 2 additional population-based studies of primary disease and 4 hospital-based studies of advanced disease, none of which studied effect modification by statins or ADT. Among these 2377 men, 1088 events of recurrence, metastasis, or prostate cancer death occurred. In a meta-analysis of all 7 studies, the genotype of the exonic SNP rs12422149 (minor allele frequency 15%) that results in lower androgen uptake was associated with better outcomes (HR per minor allele 0.80, 95% CI 0.69-0.93), with little between-study heterogeneity (I2 0.27). For the intronic SNP rs1077858, the genotype with higher SLCO2B1 mRNA expression was associated with worse outcomes (HR per minor allele 1.14, 95% CI 0.99-1.31, 3 studies with I2 0.68).

Conclusion: These results are compatible with the hypothesis that inherited genetic variation in SLCO2B1 influences androgen uptake and prostate cancer prognosis. These and other genetic variants, together with clinical features, may have potential utility as predictive biomarkers for identifying men with prostate cancer who might benefit from early therapy beyond ADT. Whether adjuvant statin therapy could mitigate the inherited risk requires further study.

Citation Format: Konrad H. Stopsack, Harisha Rajanala, Anna Plym, Jane B. Vaselkiv, Konstantina Matsoukas, Ericka M. Ebot, Sarah C. Markt, Kathryn L. Penney, Gwo-Shu M. Lee, Lorelei A. Mucci, Philip W. Kantoff. Organic anion transporter(SLCO)genotype and prostate cancer progression: Prospective cohort study and meta-analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1438.

Metabolic syndrome and its pharmacologic treatment are associated with the time to castration-resistant prostate cancer

BACKGROUND

Metabolic syndrome and its pharmacologic treatment can potentially influence the progression of prostate cancer in men receiving androgen deprivation therapy (ADT). We aimed to evaluate the association between metabolic syndrome and its pharmacologic treatment with time to castration-resistant prostate cancer (CRPC).

METHODS

We identified 409 men with metastatic castration-sensitive prostate cancer receiving first line ADT from 1996 to 2014 at our institution. Information concerning metabolic syndrome, statin use, aspirin use, and metformin use at initiation of ADT was collected from medical records. Time to CRPC was defined as the duration between initiating ADT and diagnosis of CRPC based on the Prostate Cancer Working Group 3 definition. Flexible parametric survival models were used to calculate hazard ratios (HR, and 95% confidence intervals, CI) of the association between metabolic conditions and time from ADT initiation to CRPC.

RESULTS

During a median follow-up of 59 months, 87% (N = 356) men progressed to CRPC. Median time to CRPC was 19 months. Fifty-six percent of men met the definition of metabolic syndrome. Controlling for demographic and prostate cancer-specific variables, metabolic syndrome was associated with shorter time to CRPC (HR 1.41, 95% CI 1.09-1.81). Importantly, in men with metabolic syndrome, statin use was associated with a slower progression to CRPC (HR 0.70, 95% CI 0.49-0.98).

CONCLUSIONS

Our study suggests that metabolic syndrome is a risk factor for earlier progression from castration-sensitive to castration-resistant prostate cancer and raises the possibility that treatment, such as statin use, may slow the time to progression.

DNA Repair Pathways and Their Association With Lethal Prostate Cancer in African American and European American Men

Background

Altered DNA damage response (DDR) has emerged as an important mechanism for the development of aggressive prostate cancer among men of European ancestry but not other ancestry groups. Because common mechanisms for aggressive disease are expected, we explored a large panel of DDR genes and pathways to demonstrate that DDR alterations contribute to development of aggressive prostate cancer in both African American and European American men.

Methods

We performed a case-case study of 764 African American and European American men with lethal or indolent prostate cancer treated at 4 US hospitals. We calculated carrier frequencies of germline pathogenic or likely pathogenic sequence variants within 306 DDR genes, summarized by DDR pathway, and compared lethal cases against indolent cases using 2-sided Fisher’s exact tests. Secondary analysis examined if carrier frequencies differed by ancestry.

Results

Lethal cases were more likely to carry a pathogenic sequence variant in a DDR gene compared with indolent cases (18.5% vs 9.6%, P = 4.30 × 10⁻⁴), even after excluding BRCA2 (14.6% vs 9.6%, P = .04). The carrier frequency was similar among lethal cases of African (16.7% including and 15.8% excluding BRCA2) and lethal cases of European (19.3% including and 14.2% excluding BRCA2) ancestry. Three DDR pathways were statistically significantly associated with lethal disease: homologous recombination (P = .003), Fanconi anemia (P = .002), and checkpoint factor (P = .02).

Conclusions

Our findings suggest that altered DDR is an important mechanism for aggressive prostate cancer not only in men of European but also of African ancestry. Therefore, interrogation of entire DDR pathways is needed to fully characterize and better define genetic risk of lethal disease.

Abstract 822: Can the genetic risk of prostate cancer be attenuated by a healthy lifestyle

Introduction: Inherited genetic factors contribute significantly to prostate cancer risk and explains 58% of the variability in prostate cancer incidence. It is unclear if the increased genetic risk of prostate cancer, including progression to lethal disease, can be offset by adherence to a healthy lifestyle.

Methods: Using a validated polygenic risk score (PRS) for overall prostate cancer, we quantified the genetic risk of prostate cancer in 10,443 men in the Health Professionals Follow-up Study for whom genotype data was available. We applied a validated lifestyle score for lethal prostate cancer (including healthy weight, vigorous physical activity, not smoking, and high consumption of tomatoes, fatty fish, and reduced intake of processed meat) and examined the incidence of overall and lethal (metastatic disease or prostate cancer-specific death) prostate cancer from the date of blood (1993-1999) or cheek collection (2005-2006) through 2014 (2016 for lethal disease). Multivariable Cox proportional hazards models were used to estimate the risk of overall and lethal prostate cancer by joint categories of genetic risk (PRS quartiles) and a time-varying lifestyle score (1-2: least healthy, 3: moderate healthy, and 4-6: most healthy). Both unweighted and inverse probability weighted (IPW) models (to account for possible bias arising from the genotype sampling design) were applied. Lifetime cumulative incidence was estimated using regression standardization.

Results: We observed 2,111 prostate cancer and 238 lethal prostate cancer events during a median follow-up of 18 and 22 years, respectively. The PRS enabled risk stratification for both overall and lethal prostate cancer, with men in the highest genetic risk quartile having a 5.4-fold increased risk of overall prostate cancer (HRipw = 5.39, 95% CI = 4.59-6.33) and a 3.5-fold increased risk of lethal prostate cancer (HRipw = 3.53, 95% CI = 2.34-5.32) compared with men in the lowest genetic risk quartile. Among men in the highest genetic risk quartile, adhering to a healthy lifestyle was significantly associated with a decreased risk of lethal prostate cancer (HRipw = 0.54, 95% CI = 0.31-0.94) compared with the least healthy lifestyle. Adhering to healthy lifestyle was not associated with a decreased risk of overall prostate cancer (HRipw = 1.01, 95% CI = 0.84-1.22). In the group of men with highest genetic risk, having a healthy lifestyle at study entry was associated with a lifetime cumulative incidence of lethal prostate cancer of 3%, lower than for men having the least healthy lifestyle (6%) and similar to the population average (3%).

Conclusion: In this large prospective cohort of US men, inherited genetic factors increased the risk of both overall and lethal prostate cancer. The associated decreased risk of aggressive disease in those with a favorable lifestyle may suggest that the excess genetic risk of lethal prostate cancer could be offset by adhering to a healthy lifestyle.

Citation Format: Anna Plym, Yiwen Zhang, Konrad Stopsack, Bénédicte Delcoigne, Adam S. Kibel, Edward Giovannucci, Kathryn L. Penney, Lorelei A. Mucci. Can the genetic risk of prostate cancer be attenuated by a healthy lifestyle [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 822.

Evaluation of a Multiethnic Polygenic Risk Score Model for Prostate Cancer

Polygenic risk scores (PRSs) of common genetic variants have shown promise in prostate cancer risk stratification, but their validity across populations has yet to be confirmed. We evaluated a multiethnic PRS model based on 269 germline genetic risk variants (261 were available for analysis) using an independent population of 13 628 US men. The PRS was strongly associated with prostate cancer but not with any other disease. Comparing men in the top PRS decile with those at average risk (40%-60%), the odds ratio of prostate cancer was 3.89 (95% confidence interval = 3.24 to 4.68) for men of European ancestry and 3.81 (95% confidence interval = 1.48 to 10.19) for men of African ancestry. By age 85 years, the cumulative incidence of prostate cancer for European American men was 7.1% in the bottom decile and 54.1% in the top decile. This suggests that the PRS can be used to identify a substantial proportion of men at high risk for prostate cancer.

Impact of chemotherapy, radiotherapy, and endocrine therapy on sick leave in women with early-stage breast cancer during a 5-year period: a population-based cohort study

Purpose

To examine the influence of type of oncological treatment on sick leave in women of working age with early-stage breast cancer.

Methods

We identified 8870 women aged 30–64 diagnosed with stage I–II breast cancer between 2005 and 2012 in the Breast Cancer Data Base Sweden. Associations between type of oncological treatment (radiotherapy, endocrine therapy, and chemotherapy) and sick leave were estimated by hazard ratios, probabilities, and length of sick leave using multi-state survival analysis.

Results

During the first 5 years after diagnosis, women aged 50–54 years at diagnosis receiving chemotherapy spent on average 182 (95% CI 151–218) additional days on sick leave compared with women not receiving chemotherapy, but with otherwise similar characteristics. Correspondingly, women initiating endocrine therapy spent 30 (95% CI 18–44) additional days on sick leave and women receiving post-mastectomy radiotherapy 53 (95% CI 37–69) additional days. At year five, the rate of sick leave was increased in women who had received chemotherapy (HR 1.19, 95% CI 1.11–1.28) or endocrine therapy (HR 1.15, 95% CI 1.05–1.26). Chemotherapy and endocrine therapy were associated with increased rates of sick leave due to depression or anxiety.

Conclusion

Our findings of increased long-term risks of sick leave after oncological treatment for breast cancer warrant attention from caregivers taking part in cancer rehabilitation. In light of the ongoing debate about overtreatment of early-stage breast cancer, our findings point to the importance of properly selecting patients for chemotherapy not only for the medical toxicity but also the possible impact on their livelihood.

Electronic supplementary material

The online version of this article (10.1007/s10549-020-05720-4) contains supplementary material, which is available to authorized users.

Association of diabetes with stroke and post-stroke dementia: A population-based cohort study

INTRODUCTION

The impact of prediabetes and diabetes on stroke and the development of dementia after a stroke remain unclear.

METHODS

A total of 2655 dementia-free participants (including a stroke-free cohort and a prevalent stroke cohort) were followed-up for 12 years. Dementia and post-stroke dementia were determined by clinical examinations and national registry data. Diabetes was ascertained via medical examination, medication use, medical records, or glycated hemoglobin (HbA1c) ≥6.5%. Prediabetes was defined as HbA1c ≥5.7% in diabetes-free participants.

RESULTS

In the stroke-free cohort, 236 participants developed ischemic stroke, and 47 developed post-stroke dementia. Diabetes was associated with ischemic stroke (hazard ratio [HR] 1.76, 95% confidence interval [CI] 1.16 to 2.67) and post-stroke dementia (HR 2.56, 95% CI 1.04 to 6.25). In the prevalent stroke cohort, diabetes was also related to dementia risk. Prediabetes was not significantly related to stroke or post-stroke dementia.

DISCUSSION

Diabetes, but not prediabetes, is associated with an increased risk of ischemic stroke and post-stroke dementia.

Duration of sick leave after active surveillance, surgery or radiotherapy for localised prostate cancer: a nationwide cohort study

OBJECTIVES

To compare the loss of working time due to sick leave by treatment strategy for localised prostate cancer.

DESIGN

Nationwide cohort study.

SETTING

Sweden.

PARTICIPANTS

A total of 15 902 working-aged men with localised low or intermediate-risk prostate cancer diagnosed during 2007-2016 from the Prostate Cancer Data Base Sweden, together with 63 464 prostate cancer-free men. Men were followed until 2016.

PRIMARY AND SECONDARY OUTCOME MEASURES

Using multistate Markov models, we calculated the proportion of men on work, sick leave, disability pension and death, together with the amount of time spent in each state. All-cause and cause-specific estimates were calculated.

RESULTS

During the first 5 years after diagnosis, men with active surveillance as their primary treatment strategy spent a mean of 17 days (95% CI 15 to 19) on prostate cancer-specific sick leave, as compared with 46 days (95% CI 44 to 48) after radical prostatectomy and 44 days (95% CI 38 to 50) after radiotherapy. The pattern was similar after adjustment for cancer and sociodemographic characteristics. There were no differences between the treatment strategies in terms of days spent on sick leave due to depression, anxiety or stress. Five years after diagnosis, over 90% of men in all treatment strategies were free from sick leave, disability pension receipt and death from any cause.

CONCLUSIONS

Men on active surveillance experienced less impact on working life compared with men who received radical prostatectomy or radiotherapy. From a long-term perspective, there were no major differences between treatment strategies. Our findings can inform men diagnosed with localised prostate cancer on how different treatment strategies may affect their working lives.

Loss in working years after a breast cancer diagnosis: A population-based study (Sweden)

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Background: More than half of all women with breast cancer are diagnosed during working age. We present a new measure of clinical and public health relevance to estimate the loss in working years after a breast cancer diagnosis. Methods: Women of working age diagnosed with breast cancer between 1997 and 2012 were identified in the Breast Cancer Data Base Sweden (N = 19,661), together with a breast cancer-free comparison cohort (N = 81,303). Women were followed until permanent exit from the labour market (defined as receipt of disability pension, old-age retirement or death) or censoring. Using flexible parametric survival modelling, the loss in working years was calculated as the difference in the remaining years in the work force between women with and women without breast cancer. Results: The loss in working years was most pronounced in women of younger ages and in women with advanced stage disease. Women aged 50 years at diagnosis with stage I disease lost on average 0.6 years (95% CI, 0.4-0.8) of their remaining working time; the corresponding estimates were 1.2 years (1.0-1.5) in stage II, 3.2 years (2.7-3.7) in stage III, and 8.8 years (7.9-9.8) in stage IV disease. Type of treatment was a clear determinant in women with early stage disease, with a higher loss in working years among women treated with axillary surgery, mastectomy and chemotherapy. Conclusions: Our measure provides a new perspective of the burden of breast cancer in women of working age. The modest loss in working years in women with early stage disease is reassuring, although the economic consequences on a population-level are likely to be high given the large number of women diagnosed with breast cancer every year.

Mortality in women with pregnancy-associated malignant melanoma

BACKGROUND

Malignant melanoma (MM) is one of the most common malignancies in young women. It remains debated whether a MM diagnosed during pregnancy or lactation has a worse prognosis.

OBJECTIVE

We sought to examine mortality in women with pregnancy-associated MM (PAMM) (diagnosed during pregnancy and up to 2-years postpartum).

METHODS

This was a population-based cohort study based on information retrieved from the Swedish Cancer and Multi-Generation Registers. Hazard ratios with 95% confidence intervals adjusted for age, period, education, parity, and tumor location were estimated.

RESULTS

In total, 6857 women and girls aged 15 to 44 years with a diagnosis of cutaneous MM between 1963 and 2009 were identified. Of these, 1019 cases were classified as PAMM. The cause-specific mortality did not differ between PAMM and MM not diagnosed near childbirth (adjusted hazard ratio 1.09, 95% confidence interval 0.83-1.42).

LIMITATIONS

Information on stage at diagnosis was available only for a subset of patients

CONCLUSION

Overall, the cause-specific mortality in women and girls with PAMM did not differ from that in women and girls with non-PAMM. The current findings do not provide evidence of an adverse prognostic influence of pregnancy or a recent birth.

Clinical characteristics, management and survival in young adults diagnosed with malignant melanoma: A population-based cohort study

BACKGROUND

Few studies to date have described the clinical features of malignant melanoma in young adulthood. Also, little is known about patterns of care in young patients. We examined and compared clinical characteristics, management and survival between young adult (15-39 years) and older adult melanoma patients in Central Sweden.

MATERIAL AND METHODS

Patients diagnosed with invasive malignant melanoma between 1997 and 2011 were identified in the Regional Quality Register of Cutaneous Malignant Melanoma in Central Sweden, a population-based register covering a source population of about two million. Data on clinical characteristics, management and survival were retrieved and compared according to age at diagnosis.

RESULTS

Of 5915 patients included in the study, 584 (9.9%) were between 15 and 39 years of age at diagnosis. Compared with older patients, young adult patients were more likely to be female, with higher proportions of thin, non-ulcerated melanomas, superficial spreading melanoma and melanomas located on the lower extremity. Young adults had shorter waiting times for surgical procedures and a higher proportion received surgical treatment according to guidelines. Overall, young patients had better relative survival than older patients. Age-related survival differences varied by stage of disease at diagnosis, and were most prominent in stage II disease.

CONCLUSION

The observed differences in clinical characteristics, management and survival between young adult and older melanoma patients call for an improved understanding of not only disease etiology but also factors driving management decisions. A better understanding of these differences may help improve care and prognosis for melanoma patients of all ages.