African American men with low-grade prostate cancer have increased disease recurrence after prostatectomy compared with Caucasian men

Racial disparities in biochemical recurrence of prostate cancer

BACKGROUND

The aim of this study was to determine the biochemical recurrence among Black and White American men with grade group 2-5 prostate cancer managed primarily by radical prostatectomy (RP).

METHODS

This was a single-institution, retrospective study evaluating biochemical recurrence by self-identified race. 163 patients who underwent RP at the University Hospitals Cleveland Medical Center between 2015-2021 were analyzed for racial differences in age at diagnosis, clinical stage, and preoperative serum prostate-specific antigen (PSA). Patients were followed for PSA recurrence (PSA ≥ 0.2 ng/ml). Multivariate analysis was used to determine clinical and pathologic variables that were significant in predicting biochemical recurrence after RP and to determine whether race was an independent predictor of biochemical recurrence-free survival (BCRFS).

RESULTS

Of 163 patients, 82 (50.3%) were Black Americans and 81 (49.7%) were White Americans with a median age of 62.7 ranging between 38.7 to 76.3 years. The grade-specific distribution of cancer 3+4 was 54.9% versus 65.4%; 4+3 was 25.6% versus 30.9%; 4+4 was 7.3% versus 2.5%; 4+5 was 12.2% versus 1.2% in Black American and White American men. Univariate analysis of BCRFS using Kaplan-Meier method demonstrated a significant difference among levels of Gleason score between Black Americans and White Americans (P = 0.041). Multivariable analysis after controlling the effects of age, Gleason score exhibited no significant difference of BCRFS comparing Black and White American men (P = 0.145). Specifically, the hazard of biochemical recurrence among Black Americans was 1.6 times (95% CI: 0.85-3.02) compared to White Americans (P = 0.145).

CONCLUSION

Our study demonstrated a significant difference in BCRFS between Black and White American patients. Additional studies with larger sample size underlying this clinical disparity are warranted.

Molecular and pathological subtypes related to prostate cancer disparities and disease outcomes in African American and European American patients

Prostate cancer (PCa) disproportionately affects African American (AA) men, yet present biomarkers do not address the observed racial disparity. The objective of this study was to identify biomarkers with potential benefits to AA PCa patients. Differentially expressed genes (DEG) analysis coupled with gene set enrichment analysis (GSEA) and leading-edge genes analysis showed that the keratin family of genes, including KRT8, KRT15, KRT19, KRT34, and KRT80, constituted the single most prominent family of genes enriched in AA compared to European American (EA) PCa cell lines. In PCa patients (TCGA and MSKCC patient cohorts), KRT8, KRT15, and KRT19 expression were relatively higher in AA than in EA patients. The differences in the expression of KRT15 and KRT19, but not KRT8, were enhanced by Gleason score and ERG fusion status; in low Gleason (Gleason ≤ 6 [TCGA cohort] and Gleason ≤ 7 [MSKCC cohort]), the expression of KRT15 and KRT19 was significantly (p ≤ 0.05) higher in AA than in EA patients. Survival analysis revealed that high expression of KRT15 and KRT19 was associated with increased risk of biochemical recurrence in low Gleason category patients in the TCGA patient cohort. Interestingly, KRT15 and KRT19 expression were also associated with an increased risk of death in the metastatic prostate adenocarcinoma cohort, suggesting the potential to predict the risks of disease recurrence and death in the low Gleason category and advanced disease conditions respectively. Gene set enrichment analysis revealed known oncogenic gene signatures, including KRAS and ERBB2, to be enriched in patients expressing high KRT15 and KRT19. Furthermore, high KRT15 and KRT19 were linked to the basal and LumA PCa subtypes, which are associated with poor postoperative androgen deprivation therapy (ADT) response compared to the LumB subtype. Taken together, the present study identifies genes with high expression in AA than in EA PCa. The identified genes are linked to oncogenic gene signatures, including KRAS and ERBB2, and to basal and LumA PCa subtypes that are associated with poor postoperative ADT response. This study, therefore, reveals biomarkers with the potential to address biomarker bias in PCa risk stratification and/or prognosis.

A Systematic Review of the Treatment Outcomes among Prostate Cancer Patients in Africa

Prostate cancer (PCa) is associated with a significant public health burden in Africa. This systematic review aimed to assess treatment outcomes among PCa patients in Africa. A systematic search of the literature was conducted from 1 December 2021 to 31 March 2022 to identify relevant published studies. PubMed, EMBASE, CINAHL, and Google Scholar databases were used. Twenty-four studies met the inclusion criteria, and the mean age was 68 years. Localized and locally advanced diseases had relatively higher overall survival than metastatic diseases. In metastatic disease, the mean overall five-year survival was 42% which is shorter than the Asian population (61.9%).

Race-specific prostate cancer outcomes in a cohort of military health care beneficiaries undergoing surgery: 1990-2017

Background

There is substantial variability in prostate cancer (PCa) mortality rates across Caucasian American (CA), African American (AA), Asian, and Hispanic men; however, these estimates are unable to disentangle race or ethnicity from confounding factors. The current study explores survival differences in long‐term PCa outcomes between self‐reported AA and CA men, and examines clinicopathologic features across self‐reported CA, AA, Asian, and Hispanic men.

Methods

This retrospective cohort study utilized the Center for Prostate Disease Research (CPDR) Multi‐center National Database from 1990 to 2017. Subjects were consented at military treatment facilities nationwide. AA, CA, Asian, or Hispanic men who underwent radical prostatectomy (RP) for localized PCa within the first year of diagnosis were included in the analyses. Time from RP to biochemical recurrence (BCR), BCR to metastasis, and metastasis to overall death were evaluated using Kaplan–Meier unadjusted estimation curves and adjusted Cox proportional hazards regression.

Results

This study included 7067 men, of whom 5155 (73%) were CA, 1468 (21%) were AA, 237 (3%) were Asian, and 207 (3%) were Hispanic. AA men had a significantly decreased time from RP to BCR compared to CA men (HR = 1.25, 95% CI = 1.06–1.48, p = 0.01); however, no difference was observed between AA and CA men for a time from BCR to metastasis (HR = 0.73, 95% CI = 0.39–1.33, p = 0.302) and time from metastasis to overall death (HR = 0.67, 95% CI = 0.36–1.26, p = 0.213).

Conclusions

In an equal access health care setting, AA men had a shorter survival time from RP to BCR, but comparable survival time from BCR to metastasis and metastasis to overall death.

Access and Representation: A Narrative Review of the Disparities in Access to Clinical Trials and Precision Oncology in Black men with Prostate Cancer

OBJECTIVE

To provide commentary on the disparities in access to clinical trials and precision oncology specific to Black men with Prostate Cancer (PCa) in the United States and lend a general framework to aid in closing these gaps.

MATERIALS AND METHODS

The ideas, commentaries and data presented in this narrative review were synthesized by utilizing qualitative and quantitative studies, reviews, and randomized control trials performed between 2010 and 2021. We searched PubMed using the key words "Medicaid", "Medicare", "clinical trials", "African Americans", "Black", "underrepresentation", "access", "Prostate Cancer", "minority recruitment", "racial disparities", "disparity", "genomics", "biomarkers", "diagnostic" "prognostic", "validation", "precision medicine", and "precision oncology" to identify important themes, trends and data described in the current review. Keywords were used alone and combination with both "AND" and "OR" terms.

RESULTS

Black men with prostate cancer (PCa) in the United States have earlier onset of disease, present with more advanced stages, and worse prostate cancer-specific survival than their White counterparts. Potential causative factors vary from disparities in health care access to differences in tumor immunobiology and genomics along with disparate screening rates, management patterns and underrepresentation in clinical and translational research such as clinical trials and precision oncology.

CONCLUSION

To avoid increasing the racial disparity in PCa outcomes for Black men, we must increase inclusion of Black men into precision oncology and clinical trials, using multilevel change. Underrepresentation in clinical and translational research may potentiate poorly validated risk calculators and biomarkers, leading to poor treatment decisions in high-risk populations. Relevant actions include funding to include minority-serving institutions as recruitment sites, and inclusion of evidence based recruitment methods in funded research to increase Black representation in clinical trials and translational research.

Prostate Cancer Racial Disparities: A Systematic Review by the Prostate Cancer Foundation Panel

CONTEXT

Prostate cancer (PCa) is a complex disease that disproportionately impacts Black men in the USA. The structural factors that drive heterogeneous outcomes for patients of differing backgrounds are probably the same ones that result in population-level disparities. The relative contribution of drivers along the PCa disease continuum is an active area of investigation and debate.

OBJECTIVE

To critically synthesize the available evidence on PCa disparities from a population-level perspective in comparison to data from "equal access and equal care settings" and to provide a consensus summary of the state of PCa disparities.

EVIDENCE ACQUISITION

A plenary panel on PCa disparities presented at the Prostate Cancer Foundation meeting on October 24, 2019 and ensuing discussions are reported here. We used a systematic literature review approach and the Preferred Reporting Items for Systematic Reviews and Meta-analyses to select the most relevant publications. A total of 3333 publications between 2011 and 2021 were retrieved, of which 52 were included in the review; an additional 13 articles on screening guidelines, seminal clinical trials, and statistical methodology were used in the evidence synthesis.

EVIDENCE SYNTHESIS

Race disparities in PCa are a result of a complex interaction between socioeconomic factors impacting access to care and ancestral/genetic factors that may influence tumor biology. Black men in the USA continue to have a nearly 1.8 times higher population-level mortality rate than White men. Failure to account for the race-specific incidence burden would continue to lead to residual disparity even after achieving relatively similar outcomes after primary treatment, resulting in a higher long-term mortality burden. Selection bias remains possible in PCa studies, which often rely on highly specific cohorts of Black men with higher use of health care resources that may not represent the average Black patient in the USA. Novel methods including mediation analysis and genetic ancestry rather than self-identified race can optimize analytical models investigating racial disparities and may lead to a better understanding of PCa genomic diversity and behavior.

CONCLUSIONS

Our findings emphasize the importance of racially diverse studies, including precision -omics, prevention, and targeted therapy initiatives, to elucidate mechanisms underlying racial differences in outcomes and response to therapy. We propose novel approaches for studying and addressing PCa disparities. Contemporary methods, particularly in the domain of mediation analysis, can promote scientific rigor in understanding these disparities.

PATIENT SUMMARY

Inaccurate data interpretation or lack of data altogether for Black men can impact policy and ultimately affect millions of individuals of African origin worldwide. Our review identifies a need to develop and prioritize a strategy for including Black and other men with prostate cancer in intervention studies and randomized clinical trials to halt the widening prostate cancer disparities.

Susceptibility-Associated Genetic Variation in NEDD9 Contributes to Prostate Cancer Initiation and Progression

Although American men of European ancestry represent the largest population of patients with prostate cancer, men of African ancestry are disproportionately affected by prostate cancer, with higher prevalence and worse outcomes. These racial disparities in prostate cancer are due to multiple factors, but variations in genomic susceptibility such as SNP may play an important role in determining cancer aggressiveness and treatment outcome. Using public databases, we have identified a prostate cancer susceptibility SNP at an intronic enhancer of the neural precursor expressed, developmentally downregulated 9 (NEDD9) gene, which is strongly associated with increased risk of patients with African ancestry. This genetic variation increased expression of NEDD9 by modulating the chromatin binding of certain transcription factors, including ERG and NANOG. Moreover, NEDD9 displayed oncogenic activity in prostate cancer cells, promoting prostate cancer tumor growth and metastasis in vitro and in vivo. Together, our study provides novel insights into the genetic mechanisms driving prostate cancer racial disparities. SIGNIFICANCE: A prostate cancer susceptibility genetic variation in NEDD9, which is strongly associated with the increased risk of patients with African ancestry, increases NEDD9 expression and promotes initiation and progression of prostate cancer.See related commentary by Mavura and Huang, p. 3764.

Interrelationship Between Health Insurance Status and Prostate Cancer Grade Can Have Critical Impact on Prostate Cancer Disease Control: A Retrospective Cohort Study

The extent to which prostate cancer (PCa) pathology interacts with health insurance to predict PCa outcomes remains unclear. This study will assess the overall association of health insurance on PCa disease control and analyze its interrelationship PCa pathology. A total of 674 PCa patients, treated with prostatectomy from 1987 to 2015, were included in the study. Freedom from biochemical failure (FFbF) was used as a measure of PCa disease control. Methods of categorical and survival analysis were used to analyze the relationships between health insurance, PCa pathology, and FFbF. A total of 63.3% patients were privately insured, 27.1% were publicly insured, and 9.5% were uninsured. In a multivariable model, privately (hazard ratio [HR] = 0.64, 95% confidence interval [CI]: 0.42-0.97, P = .03) and publicly (HR = 0.65, 95% CI: 0.41-1.04, P = .07) insured patients showed improvement in FFbF compared to uninsured patients. The association of health insurance was significantly stronger for the patients with pathologically low grade PCa (pathologic Gleason Score 3+3 & preoperative prostate-specific antigen ≤10 ng/mL), likelihood ratio P = .009. Privately (HR = 0.22, 95% CI: 0.10-0.46) or publicly (HR = 0.26, 95% CI: 0.11-0.60) insured patients with low grade PCa demonstrated favorable association with FFbF. Patients with private and public insurance were more likely to experience favorable treatment. The association of health insurance on PCa disease control is significantly stronger among patients with pathologically low grade PCa. This study identifies health insurance status as pretreatment surrogate for PCa disease control.

African American Specific Gene Panel Predictive of Poor Prostate Cancer Outcome

PURPOSE

Most prostate cancer in African American men lacks the ETS (E26 transforming specific) family fusion event (ETS-). We aimed to establish clinically relevant biomarkers in African American men by studying ETS dependent gene expression patterns to identified race specific genes predictive of outcomes.

MATERIALS AND METHODS

Two multicenter cohorts of a total of 1,427 men were used for the discovery and validation (635 and 792 men, respectively) of race specific predictive biomarkers. We used false discovery rate adjusted q values to identify race and ETS dependent genes which were differentially expressed in African American men who experienced biochemical recurrence within 5 years. Principal component modeling along with survival analysis was done to assess the accuracy of the gene panel in predicting recurrence.

RESULTS

We identified 3,047 genes which were differentially expressed based on ETS status. Of these genes 362 were differentially expressed in a race specific manner (false discovery rate 0.025 or less). A total of 81 genes were race specific and over expressed in African American men who experienced biochemical recurrence. The final gene panel included APOD, BCL6, EMP1, MYADM, SRGN and TIMP3. These genes were associated with 5-year biochemical recurrence (HR 1.97, 95% CI 1.27-3.06, p = 0.002) and they improved the predictive accuracy of clinicopathological variables only in African American men (60-month time dependent AUC 0.72).

CONCLUSIONS

In an effort to elucidate biological features associated with prostate cancer aggressiveness in African American men we identified ETS dependent biomarkers predicting early onset biochemical recurrence only in African American men. Thus, these ETS dependent biomarkers representing ideal candidates for biomarkers of aggressive disease in this patient population.

Receptor tyrosine kinase recepteur d'origine nantais as predictive marker for aggressive prostate cancer in African Americans

Published evidence shows a correlation between several molecular markers and prostate cancer (PCa) progression including in African Americans (AAs) who are disproportionately affected. Our early detection efforts led to the identification of elevated levels of antiapoptotic protein, c-FLIP and its upstream regulatory factors such as androgen receptor (AR), recepteur d'origine nantais (RON), a receptor tyrosine kinase in human prostate tumors. The primary objective of this study was to explore whether these markers play a role in racial disparities using immunohistochemistry in prostatectomy samples from a cohort of AA, Hispanic Whites (HWs), and non-Hispanic Whites (NHWs). Bivariable and multivariable logistic regression analyses were used to identify a statistical association between molecular markers, possible correlation with risk factors including race, obesity, prostate-specific antigen (PSA) and disease aggressiveness. Further, changes in the levels and expression of these molecular markers were also evaluated using human PCa cell lines. We found significantly elevated levels of RON ( P = 0.0082), AR ( P = 0.0001), c-FLIP ( P = 0.0071) in AAs compared with HWs or NHWs. Furthermore, a higher proportion of HW and NHWs had a high Gleason score (>6) but not PSA as compared to AAs ( P = 0.032). In summary, our findings suggest that PSA was important in predicting aggressive disease for the cohort overall; however, high levels of RON may play a role in predisposing AA men to develop aggressive disease. Future research is needed using large datasets to confirm these findings and to explore whether all or any of these markers could aid in race-specific stratification of patients for treatment.

Optimizing Time to Treatment to Achieve Durable Biochemical Disease Control after Surgery in Prostate Cancer: A Multi-Institutional Cohort Study

BACKGROUND

The impact of treatment delays on prostate cancer-specific outcomes remains ill-defined. This study investigates the effect of time to treatment on biochemical disease control after prostatectomy.

METHODS

This retrospective study includes 1,807 patients who received a prostatectomy as a primary treatment at two large tertiary referral centers from 1987 to 2015. Multivariate cox model with restricted cubic spline was used to identify optimal time to receive treatment and estimate the risk of biochemical recurrence.

RESULTS

Median follow-up time of the study was 46 (interquartile range, 18-86) months. Time to treatment was subcategorized based on multivariate cubic spline cox model. In multivariate spline model, adjusted for all the pertinent pretreatment variables, inflection point in the risk of biochemical recurrence was observed around 3 months, which further increased after 6 months. Based on spline model, time to treatment was then divided into 0 to 3 months (61.5%), >3 to 6 months (31.1%), and 6 months (7.4%). In the adjusted cox model, initial delays up to 6 months did not adversely affect the outcome; however, time to treatment >6 months had significantly higher risk of biochemical recurrence (HR, 1.84; 95% confidence interval, 1.30-2.60; P < 0.01).

CONCLUSIONS

The initial delays up to 6 months in prostate cancer primary treatment may be sustainable without adversely affecting the outcome. However, significant delays beyond 6 months can unfavorably affect biochemical disease control.

IMPACT

Time to treatment can aid clinicians in the decision-making of prostate cancer treatment recommendation and educate patients against unintentional treatment delays.

Prostate Cancer Disparities by Race and Ethnicity: From Nucleotide to Neighborhood

Prostate cancer (CaP) incidence, morbidity, and mortality rates vary substantially by race and ethnicity, with African American men experiencing among the highest CaP rates in the world. The causes of these disparities are multifactorial and complex, and likely involve differences in access to screening and treatment, exposure to CaP risk factors, variation in genomic susceptibility, and other biological factors. To date, the proportion of CaP that can be explained by environmental exposures is small and differences in the role factors play by race or ethnicity is poorly understood. In the absence of additional data, it is likely that environmental factors do not contribute greatly to CaP disparities. In contrast, CaP has one of the highest heritabilities of all major cancers and many CaP susceptibility genes have been identified. Some CaP loci, including the risk loci found at chromosome 8q24, have consistent effects in all racial/ethnic groups studied to date. However, replication of many susceptibility loci across race or ethnicity remains limited. It is likely that inequities in health care access strongly influences CaP disparities. CaP is a disease with a complex multifactorial etiology, and therefore any approach attempting to address racial/ethnic disparities in CaP must consider the many sources that influence risk, outcomes, and disparities.

Rethinking active surveillance for prostate cancer in African American men

Active surveillance (AS) is a treatment modality for prostate cancer that aims to simultaneously avoid overtreatment and allow for the timely intervention of localized disease. AS has become the de facto standard of care for most men with low-risk prostate cancer. However, few African American (AA) men were included in the prospective observational cohorts that resulted in a paradigm shift in treatment recommendations from active intervention toward AS. It has been established that AA men have an increased prostate cancer incidence, higher baseline prostate-specific antigen (PSA) values, more aggressive prostate cancer features, greater frequency of biochemical recurrence after treatment, and higher overall cancer-specific mortality compared to their Caucasian counterparts. As such, this has given many physicians pause before initiating AS for AA patients. In the following manuscript, we will review the available literature regarding AS, with a particular focus on AA men. The preponderance of evidence demonstrates that AS is as viable a management method for AA with low-risk prostate cancer as it is with other racial groups.

African-American men and prostate cancer-specific mortality: a competing risk analysis of a large institutional cohort, 1989-2015

Significant racial disparities in prostate cancer (PCa) outcomes have been reported, with African-American men (AAM) more likely to endure adverse oncologic outcomes. Despite efforts to dissipate racial disparities in PCa, a survival gap persists and it remains unclear to what extent this disparity can be explained by known clinicodemographic factors. In this study, we leveraged our large institutional database, spanning over 25 years, to investigate whether AAM continued to experience poor PCa outcomes and factors that may contribute to racial disparities in PCa. A total of 7307 patients diagnosed with PCa from 1989 through 2015 were included. Associations of race and clinicodemographic characteristics were analyzed using chi-square for categorical and Mann-Whitney U-test for continuous variables. Racial differences in prostate cancer outcomes were analyzed using competing risk analysis methods of Fine and Gray. Median follow-up time was 106 months. There were 2304 deaths recorded, of which 432 resulted from PCa. AAM were more likely to be diagnosed at an earlier age (median 60 vs. 65 years, P = <0.001) and were more likely to have ≥1 comorbidities (13.6% vs. 7.5%, P < 0.001). In a multivariate competing risk model, adjusted for baseline covariates, AAM experienced significantly higher risk of PCSM compared to NHW men (HR, 1.62, 95% CI, 1.02-2.57, P = 0.03) NHW. Among men diagnosed at an older age (>60 years), racial differences in PCSM were more pronounced, with AAM experiencing higher rates of PCSM (HR, 2.05, 95% CI, 1.26-3.34, P = 0.003). After adjustment of clinicodemographic and potential risk factors, AAM continue to experience an increased risk of mortality from PCa, especially older AAM. Furthermore, AAM are more likely to be diagnosed at an early age and more likely to have higher comorbidity indices.

68Ga-PSMA-11 PET/CT in primary staging of prostate carcinoma: preliminary results on differences between black and white South-Africans

PURPOSE

The incidence of prostate cancer is 60% higher and the mortality rate is two- to three-times greater in black versus white men. We report on differences in ⁶⁸Ga-PSMA-11 PET/CT imaging findings in 77 black South-African (BSAs) and 18 white South-African (WSAs) treatment-naïve primary prostate carcinoma (PPC) patients.

METHODS

⁶⁸Ga-PSMA-11 PET/CT imaging findings were compared to histological, biochemical and morphological imaging data. Patients were grouped into three Gleason grade groups (GG), GG 1 (scores 3 + 3 and 3 + 4), GG2 (scores 4 + 3 and 4 + 4) and GG3 (scores 9 and 10), and the PSA difference among the groups was determined. Inter-racial difference in SUVmax of the primary tumor as well as its correlation with serum PSA were also determined.

RESULTS

Ninety-three out of 95 PPC where readily identified on ⁶⁸Ga-PSMA-11 PET/CT imaging. Median PPC SUVmax and serum PSA values proved significantly higher (p = 0.033 and p = 0.003) in GG3 patients (median 16.4 and 180 ng/ml) when compared to GG1 patients (median 9.6 and 25.1 ng/ml) or GG2 patients (median 8.8 and 46.2 ng/ml). SUVmax significantly correlated with serum PSA-values (r = 0.377 (p = 0.0001)). Age, frequency of lymph node involvement and distant metastases, and GGs (p ≥ 0.153) were similar in BSAs and WSAs, both median serum PSA-values as well as SUVmax values proved significantly higher in BSAs when compared to WSAs, respectively, 81.6 ng/ml versus 14.5 ng/ml (p = 0.0001) and 11.9 versus 4.38 (p = 0.004). Moreover, Gleason-score normalized median SUVmax values proved 2.5 times higher in BSAs when compared to WSAs (p = 0.005).

CONCLUSION

SUVmax values proved significantly related to GG and to be significantly higher in BSAs when compared to WSAs. Also, SUVmax significantly correlated with serum PSA values, which was significantly higher in BSAs when compared with WSAs.

Race and risk of metastases and survival after radical prostatectomy: Results from the SEARCH database

BACKGROUND

Black race is associated with prostate cancer (PC) diagnosis and poor outcome. Previously, the authors reported that black men undergoing radical prostatectomy (RP) in equal-access hospitals had an increased risk of biochemical disease recurrence (BCR), but recurrences were equally aggressive as those occurring in white men. The authors examined the association between race and long-term outcomes after RP.

METHODS

Data regarding 1665 black men (37%) and 2791 white men (63%) undergoing RP were analyzed. Using Cox models, the authors tested the association between race and BCR, BCR with a prostate-specific antigen (PSA) doubling time <9 months (aggressive disease recurrence), metastases, PC-specific death, and overall death.

RESULTS

At a median follow-up of 102 months, 1566 men (35%) developed BCR, 217 men (5%) experienced aggressive disease recurrence, 193 men (4%) developed metastases, and 1207 men (27%) had died, 107 of whom (2%) died of PC. White men were older and had a lower preoperative PSA level, a lower biopsy and pathological grade group, and more capsular penetration but less seminal vesicle invasion and positive surgical margins versus black men (all P<.05). Black men were found to have a more recent surgery year (P<.001). On univariable analysis, black race was associated with increased BCR (P = .003) and reduced overall death (P = .017). On multivariable analysis, black race was not found to be associated with BCR (hazard ratio [HR], 1.07; P = .26), aggressive recurrence (HR, 1.14; P = .42), metastasis (HR, 1.24; P = .21), PC-specific death (HR, 1.03; P = .91), or overall death (HR, 1.03; P = .67).

CONCLUSIONS

Among men undergoing RP at equal-access centers, although black men were found to have an increased risk of BCR, they had similar risks of aggressive disease recurrence, metastasis, and PC-specific death compared with white men, and the risk of BCR was found to be similar after controlling for risk parameters. Longer follow-up is needed to confirm these findings. Cancer 2017;123:4199-4206. © 2017 American Cancer Society.

Prostate cancer screening practices in a large, integrated health system: 2007-2014

OBJECTIVES

To assess prostate cancer screening practices in primary care since the initial United States Preventive Services Task Force (USPSTF) recommendation against prostate-specific antigen (PSA) testing for older men, and to assess primary provider variation associated with prostate cancer screening.

PATIENTS AND METHODS

Our study population included 160 211 men aged ≥40 years with at least one visit to a primary care clinic in any of the study years in a large, integrated health system. We conducted a retrospective cohort study using electronic medical record data from January 2007 to December 2014. Yearly rates of screening PSA testing by primary care providers (PCPs), rates of re-screening, and rates of prostate biopsies were assessed.

RESULTS

Annual PSA-screening testing declined from 2007 to 2014 in all age groups, as did biennial and quadrennial screening. Yearly rates declined for men aged ≥70 years, from 22.8% to 8.9%; ages 50-69 years, from 39.2% to 20%; and ages 40-49 years, from 11% to 4.6%. Overall rates were lower for African-American (A-A) men vs non-A-A men; for men with a family history of prostate cancer, rates were similar or slightly higher than for those without a family history. PCP variation associated with ordering of PSA testing did not substantially change after the USPSTF recommendations. While the number of men screened and rates of follow-up prostate cancer screening declined in 2011-2014 compared to 2007-2010, similar re-screening rates were noted for men aged 45-75 years with initial PSA levels of <1 ng/mL or 1-3 ng/mL in both the earlier and later cohorts. For men aged >75 years with initial PSA levels of <3 ng/mL screened in both cohorts, follow-up screening rates were similar. Rates of prostate biopsy declined for men aged ≥70 years in 2014 compared to 2007. For men who had PSA screening, rates of first prostate biopsy increased in later years for A-A men and men with a family history of prostate cancer.

CONCLUSIONS

Prostate cancer screening declined from 2007 to 2014 even in higher-risk groups and follow-up screening rates were not related to previous PSA level. However, rates of first prostate biopsy in men who were screened with a PSA test were higher for men with an increased risk of prostate cancer in later years. Variation in PSA testing was noted among PCPs. Future work should further explore sources of variation in screening practices and implementation of risk-based strategies for prostate cancer screening in primary care.

The Genomic Impact of DNA CpG Methylation on Gene Expression; Relationships in Prostate Cancer

The process of DNA CpG methylation has been extensively investigated for over 50 years and revealed associations between changing methylation status of CpG islands and gene expression. As a result, DNA CpG methylation is implicated in the control of gene expression in developmental and homeostasis processes, as well as being a cancer-driver mechanism. The development of genome-wide technologies and sophisticated statistical analytical approaches has ushered in an era of widespread analyses, for example in the cancer arena, of the relationships between altered DNA CpG methylation, gene expression, and tumor status. The remarkable increase in the volume of such genomic data, for example, through investigators from the Cancer Genome Atlas (TCGA), has allowed dissection of the relationships between DNA CpG methylation density and distribution, gene expression, and tumor outcome. In this manner, it is now possible to test that the genome-wide correlations are measurable between changes in DNA CpG methylation and gene expression. Perhaps surprisingly is that these associations can only be detected for hundreds, but not thousands, of genes, and the direction of the correlations are both positive and negative. This, perhaps, suggests that CpG methylation events in cancer systems can act as disease drivers but the effects are possibly more restricted than suspected. Additionally, the positive and negative correlations suggest direct and indirect events and an incomplete understanding. Within the prostate cancer TCGA cohort, we examined the relationships between expression of genes that control DNA methylation, known targets of DNA methylation and tumor status. This revealed that genes that control the synthesis of S-adenosyl-l-methionine (SAM) associate with altered expression of DNA methylation targets in a subset of aggressive tumors.

Predicting Prostate Cancer Recurrence After Radical Prostatectomy

BACKGROUND

Prostate cancer prognosis is variable, and management decisions involve balancing patients' risks of recurrence and recurrence-free death. Moreover, the roles of body mass index (BMI) and race in risk of recurrence are controversial [1,2]. To address these issues, we developed and cross-validated RAPS (Risks After Prostate Surgery), a personal prediction model for biochemical recurrence (BCR) within 10 years of radical prostatectomy (RP) that includes BMI and race as possible predictors, and recurrence-free death as a competing risk.

METHODS

RAPS uses a patient's risk factors at surgery to assign him a recurrence probability based on statistical learning methods applied to a cohort of 1,276 patients undergoing RP at the University of Pennsylvania. We compared the performance of RAPS to that of an existing model with respect to calibration (by comparing observed and predicted outcomes), and discrimination (using the area under the receiver operating characteristic curve (AUC)).

RESULTS

RAPS' cross-validated BCR predictions provided better calibration than those of an existing model that underestimated patients' risks. Discrimination was similar for the two models, with BCR AUCs of 0.793, 95% confidence interval (0.766-0.820) for RAPS, and 0.780 (0.745-0.815) for the existing model. RAPS' most important BCR predictors were tumor grade, preoperative prostate-specific antigen (PSA) level and BMI; race was less important [3]. RAPS' predictions can be obtained online at https://predict.shinyapps.io/raps.

CONCLUSION

RAPS' cross-validated BCR predictions were better calibrated than those of an existing model, and BMI information contributed substantially to these predictions. RAPS predictions for recurrence-free death were limited by lack of co-morbidity data; however the model provides a simple framework for extension to include such data. Its use and extension should facilitate decision strategies for post-RP prostate cancer management. Prostate 77:291-298, 2017. © 2016 Wiley Periodicals, Inc.

Very high-risk prostate cancer: stratification by outcomes of radiotherapy and long-term androgen deprivation therapy

AIM

The definition of very high-risk (VHR) prostate cancer is currently based on the study of radical prostatectomy. We aimed to identify a suitable definition for VHR group following external beam radiation therapy (EBRT) and long-term androgen-deprivation therapy (ADT).

METHODS

This retrospective study included 356 high-risk patients treated with EBRT and long-term ADT. A median follow-up time was 68 months. At first, associations of previously described prognostic factors with biochemical disease-free survival (bDFS), clinical relapse-free survival (cRFS) and prostate cancer-specific survival (CSS) were examined. Second, the combination of significant adverse factors in the first analysis served as VHR test definitions. For each factor, a Cox proportional hazards model was used to calculate their hazard ratios for bDFS and cRFS. The logrank test was used to evaluate the association between each factor and CSS.

RESULTS

Primary Gleason pattern 5, T4 and ≥ 5 or 4 cores with Gleason score 8-10 were risk factors associated with bDFS, cRFS and CSS. Eleven VHR test definitions composed of these adverse factors were associated significantly with bDFS, cRFS and CSS. The final definition was described by primary Gleason pattern 5 or T4 or ≥ 4 cores with Gleason score 8-10 because of the largest sample size of 38% among 11 test definitions. bDFS, cRFS and CSS of the VHR group were significantly lower compared with other high-risk patients (P < 0.001, P < 0.001 and P = 0.015, respectively).

CONCLUSION

These VHR criteria were best fitted following EBRT with long-term ADT.

miRNAs as drivers of TMPRSS2-ERG negative prostate tumors in African American men

African Americans (AAs) who have PCa typically have more aggressive disease and make up a disproportionate number of the disease deaths, relative to European Americans (EAs). TMPRSS2 translocations, a common event in EA patients, are exploited in diagnostic and prognostic settings, whereas they are diminished in frequency in AA men. Thus, these patients with TMPRSS2 fusion-negative disease represent an under-investigated patient group. We propose that epigenetic events are a significant and alternative driver of aggressive disease in fusion-negative PCa. To reveal epigenetically governed microRNAs (miRNAs) that are enriched in fusion-negative disease and associated with aggressive in AA PCa, we leveraged both our experimental evidence and publically available data. These analyses identified 18 miRNAs that are differentially altered in fusion-negative disease, associated with DNA CpG methylation, and implicated in aggressive and AA PCas. Understanding the relationships between miRNA expression, upstream epigenetic regulation by DNA methylation, and downstream regulation of mRNA targets in fusion negative disease is imperative to understanding the biological basis of the racial health disparity in PCa.

Proteomic Upregulation of Fatty Acid Synthase and Fatty Acid Binding Protein 5 and Identification of Cancer- and Race-Specific Pathway Associations in Human Prostate Cancer Tissues

Protein profiling studies of prostate cancer have been widely used to characterize molecular differences between diseased and non-diseased tissues. When combined with pathway analysis, profiling approaches are able to identify molecular mechanisms of prostate cancer, group patients by cancer subtype, and predict prognosis. This strategy can also be implemented to study prostate cancer in very specific populations, such as African Americans who have higher rates of prostate cancer incidence and mortality than other racial groups in the United States. In this study, age-, stage-, and Gleason score-matched prostate tumor specimen from African American and Caucasian American men, along with non-malignant adjacent prostate tissue from these same patients, were compared. Protein expression changes and altered pathway associations were identified in prostate cancer generally and in African American prostate cancer specifically. In comparing tumor to non-malignant samples, 45 proteins were significantly cancer-associated and 3 proteins were significantly downregulated in tumor samples. Notably, fatty acid synthase (FASN) and epidermal fatty acid-binding protein (FABP5) were upregulated in human prostate cancer tissues, consistent with their known functions in prostate cancer progression. Aldehyde dehydrogenase family 1 member A3 (ALDH1A3) was also upregulated in tumor samples. The Metastasis Associated Protein 3 (MTA3) pathway was significantly enriched in tumor samples compared to non-malignant samples. While the current experiment was unable to detect statistically significant differences in protein expression between African American and Caucasian American samples, differences in overrepresentation and pathway enrichment were found. Structural components (Cytoskeletal Proteins and Extracellular Matrix Protein protein classes, and Biological Adhesion Gene Ontology (GO) annotation) were overrepresented in African American but not Caucasian American tumors. Additionally, 5 pathways were enriched in African American prostate tumors: the Small Cell Lung Cancer, Platelet-Amyloid Precursor Protein, Agrin, Neuroactive Ligand-Receptor Interaction, and Intrinsic pathways. The protein components of these pathways were either basement membrane proteins or coagulation proteins.

Multiparametric prostate magnetic resonance imaging in the evaluation of prostate cancer

Imaging has traditionally played a minor role in the diagnosis and staging of prostate cancer. However, recent controversies generated by the use of prostate-specific antigen (PSA) screening followed by random biopsy have encouraged the development of new imaging methods for prostate cancer. Multiparametric magnetic resonance imaging (mpMRI) has emerged as the imaging method best able to detect clinically significant prostate cancers and to guide biopsies. Here, the authors explain what mpMRI is and how it is used clinically, especially with regard to high-risk populations, and we discuss the impact of mpMRI on treatment decisions for men with prostate cancer. CA Cancer J Clin 2016;66:326-336. © 2015 American Cancer Society.

Pathological and Biochemical Outcomes among African-American and Caucasian Men with Low Risk Prostate Cancer in the SEARCH Database: Implications for Active Surveillance Candidacy

PURPOSE

Racial disparities in the incidence and risk profile of prostate cancer at diagnosis among African-American men are well reported. However, it remains unclear whether African-American race is independently associated with adverse outcomes in men with clinical low risk disease.

MATERIALS AND METHODS

We retrospectively analyzed the records of 895 men in the SEARCH (Shared Equal Access Regional Cancer Hospital) database in whom clinical low risk prostate cancer was treated with radical prostatectomy. Associations of African-American and Caucasian race with pathological biochemical recurrence outcomes were examined using chi-square, logistic regression, log rank and Cox proportional hazards analyses.

RESULTS

We identified 355 African-American and 540 Caucasian men with low risk tumors in the SEARCH cohort who were followed a median of 6.3 years. Following adjustment for relevant covariates African-American race was not significantly associated with pathological upgrading (OR 1.33, p = 0.12), major upgrading (OR 0.58, p = 0.10), up-staging (OR 1.09, p = 0.73) or positive surgical margins (OR 1.04, p = 0.81). Five-year recurrence-free survival rates were 73.4% in African-American men and 78.4% in Caucasian men (log rank p = 0.18). In a Cox proportional hazards analysis model African-American race was not significantly associated with biochemical recurrence (HR 1.11, p = 0.52).

CONCLUSIONS

In a cohort of patients at clinical low risk who were treated with prostatectomy in an equal access health system with a high representation of African-American men we observed no significant differences in the rates of pathological upgrading, up-staging or biochemical recurrence. These data support continued use of active surveillance in African-American men. Upgrading and up-staging remain concerning possibilities for all men regardless of race.

The significance of anterior prostate lesions on multiparametric magnetic resonance imaging in African-American men

INTRODUCTION

African-American (AA) men tend to harbor high-risk prostate cancer (PCa) and exhibit worse outcomes when compared to other groups. It has been postulated that AA men may harbor more anterior prostate lesions (APLs) that are undersampled by the standard transrectal ultrasound guided-biopsy (SBx), potentially resulting in greater degree of Gleason score (GS) upgrading at radical prostatectomy. We aimed to evaluate the detection rate of anterior PCa significance of APLs in AA men on multiparametric magnetic resonance imaging (mpMRI) and compare it to a matched cohort of White/Other (W/O) men.

MATERIALS AND METHODS

A review of 1,267 men who had an mpMRI with suspicious prostate lesions and who underwent magnetic resonance transrectal ultrasound fusion-guided biopsy (FBx) with concurrent SBx in the same biopsy session was performed. All AA men were matched to a control group of W/O using a 1:1 propensity score-matching algorithm with age, prostate-specific antigen, and prostate volume as matching variables. Logistic regression analysis was used to determine predictors of APLs in AA men.

RESULTS

Of the 195 AA men who underwent mpMRI, 93 (47.7%) men had a total of 109 APLs. Prior negative SBx was associated with the presence of APLs in AA men (Odds ratio = 1.81; 95% CI: 1.03-3.20; P = 0.04). On multivariate logistic regression analysis, smaller prostate (P = 0.001) and rising prostate-specific antigen (P = 0.007) were independent predictors of cancer-positive APLs in AA men. Comparative analysis of AA (93/195, 47.7%) vs. W/O (100/194, 52%) showed no difference in the rates of APLs (P = 0.44) or in cancer detection rate within those lesions or the distribution of GS within those cancers (P = 0.63) despite an overall higher cancer detection rate in AA men (AA: 124/195 [63.6%] vs. W/O: 97/194 [50.0%], P = 0.007). In cases where APLs were positive for PCa on FBx, the GS of APL was equal to the highest GS of the entire gland in 82.9% (29/35) and 90.9% (30/33) of the time in AA and W/O men, respectively.

CONCLUSION

Cancer-positive APLs represented the highest risk GS in most cases. AA men with prior negative SBx are twice as likely to harbor a concerning APL. In our cohort, AA and W/O men had comparable rates of APLs on mpMRI. Thus, differences in APLs do not explain the higher risk of AA men for deahth due to PCa. However, targeting of APLs via FBx can clinically improve PCa risk stratification and guide appropriate treatment options.

Prostate cancer in men of African origin

Men of African origin are disproportionately affected by prostate cancer: prostate cancer incidence is highest among men of African origin in the USA, prostate cancer mortality is highest among men of African origin in the Caribbean, and tumour stage and grade at diagnosis are highest among men in sub-Saharan Africa. Socioeconomic, educational, cultural, and genetic factors, as well as variations in care delivery and treatment selection, contribute to this cancer disparity. Emerging data on single-nucleotide-polymorphism patterns, epigenetic changes, and variations in fusion-gene products among men of African origin add to the understanding of genetic differences underlying this disease. On the diagnosis of prostate cancer, when all treatment options are available, men of African origin are more likely to choose radiation therapy or to receive no definitive treatment than white men. Among men of African origin undergoing surgery, increased rates of biochemical recurrence have been identified. Understanding differences in the cancer-survivorship experience and quality-of-life outcomes among men of African origin are critical to appropriately counsel patients and improve cultural sensitivity. Efforts to curtail prostate cancer screening will likely affect men of African origin disproportionately and widen the racial disparity of disease.

MethylAction: detecting differentially methylated regions that distinguish biological subtypes

DNA methylation differences capture substantial information about the molecular and gene-regulatory states among biological subtypes. Enrichment-based next generation sequencing methods such as MBD-isolated genome sequencing (MiGS) and MeDIP-seq are appealing for studying DNA methylation genome-wide in order to distinguish between biological subtypes. However, current analytic tools do not provide optimal features for analyzing three-group or larger study designs. MethylAction addresses this need by detecting all possible patterns of statistically significant hyper- and hypo- methylation in comparisons involving any number of groups. Crucially, significance is established at the level of differentially methylated regions (DMRs), and bootstrapping determines false discovery rates (FDRs) associated with each pattern. We demonstrate this functionality in a four-group comparison among benign prostate and three clinical subtypes of prostate cancer and show that the bootstrap FDRs are highly useful in selecting the most robust patterns of DMRs. Compared to existing tools that are limited to two-group comparisons, MethylAction detects more DMRs with strong differential methylation measurements confirmed by whole genome bisulfite sequencing and offers a better balance between precision and recall in cross-cohort comparisons. MethylAction is available as an R package at http://jeffbhasin.github.io/methylaction.

Evolution of a CDC Public Health Research Agenda for Low-Risk Prostate Cancer

Men with prostate cancer face difficult choices when selecting a therapy for localized prostate cancer. Comparative data from controlled studies are lacking and clinical opinions diverge about the benefits and harms of treatment options. Consequently, there is limited guidance for patients regarding the impact of treatment decisions on quality of life. There are opportunities for public health to intervene at several decision-making points. Information on typical quality of life outcomes associated with specific prostate cancer treatments could help patients select treatment options. From 2003 to present, the Division of Cancer Prevention and Control at CDC has supported projects to explore patient information-seeking behavior post-diagnosis, caregiver and provider involvement in treatment decision making, and patient quality of life following prostate cancer treatment. CDC's work also includes research that explores barriers and facilitators to the presentation of active surveillance as a viable treatment option and promotes equal access to information for men and their caregivers. This article provides an overview of the literature and considerations that initiated establishing a prospective public health research agenda around treatment decision making. Insights gathered from CDC-supported studies are poised to enhance understanding of the process of shared decision making and the influence of patient, caregiver, and provider preferences on the selection of treatment choices. These findings provide guidance about attributes that maximize patient experiences in survivorship, including optimal quality of life and patient and caregiver satisfaction with information, treatment decisions, and subsequent care.

Methylome-wide Sequencing Detects DNA Hypermethylation Distinguishing Indolent from Aggressive Prostate Cancer

A critical need in understanding the biology of prostate cancer is characterizing the molecular differences between indolent and aggressive cases. Because DNA methylation can capture the regulatory state of tumors, we analyzed differential methylation patterns genome-wide among benign prostatic tissue and low-grade and high-grade prostate cancer and found extensive, focal hypermethylation regions unique to high-grade disease. These hypermethylation regions occurred not only in the promoters of genes but also in gene bodies and at intergenic regions that are enriched for DNA-protein binding sites. Integration with existing RNA-sequencing (RNA-seq) and survival data revealed regions where DNA methylation correlates with reduced gene expression associated with poor outcome. Regions specific to aggressive disease are proximal to genes with distinct functions from regions shared by indolent and aggressive disease. Our compendium of methylation changes reveals crucial molecular distinctions between indolent and aggressive prostate cancer.

Racial variation in the clinical and economic burden of skeletal-related events among elderly men with stage IV metastatic prostate cancer

Prostate cancer (PCa) outcomes vary widely among African American (AA) and non-Hispanic White (NHW) men. The authors investigated racial variation in the incidence of skeletal-related events (SREs) and SRE-related healthcare costs among AA and NHW men, a topic that has received limited attention in the literature. AA and NHW men diagnosed with metastatic PCa were identified from the linked Surveillance, Epidemiology and End Results-Medicare dataset. The sample included 6455 men with metastatic PCa, including 5420 NHW men and 1035 AA men. Approximately 16% experienced SREs during follow-up. AA men were less likely to experience SREs compared with NHW men, controlling for individual characteristics (adjusted odds ratio: 0.79; 95% CI: 0.66- 0.94). The SRE-specific costs were US$35,725 (US$22,190-US$49,260) among AA men and US$25,896 (US$21,669-US$30,123) among NHW men. Although AA men were less likely to experience SREs, there were substantial costs attributable to the treatment of SREs among AA men.