Metastatic prostate cancer is associated with distinct higher frequency of genetic mutations at diagnosis

INTRODUCTION AND OBJECTIVES

We explored characteristic genetic mutations associated with metastatic prostate cancer (PCa) by comparing next generation sequencing (NGS) data between men with or without metastatic disease at diagnosis.

METHODS

We queried the American Association for Cancer Research Project Genomics Evidence Neoplasia Information Exchange (GENIE) registry for men diagnosed with PCa. Patients were categorized into with (M1) or without metastatic disease (M0) groups. The difference in the frequency of genetic mutations between the two groups and the prognostic significance of the mutations were analyzed using SPSS V28. We included frequency rate of > 5% and P values < 0.05 were considered statistically significant to maintain over 95% true positive detection rate.

RESULTS

Of a total of 10,580 patients with diagnosis of PCa in the dataset, we selected a study cohort of 1268 patients without missing data; 700 (55.2%) had nonmetastatic PCa, 421 (33.2%) and 147 (11.6%) patients had metastatic castration sensitive and resistant PCa respectively. The median age at diagnosis and serum prostate specific antigen (PSA) level for the entire cohort was 62.8 years (IQR 56.3-68.4) and 8.0 ng/ml (IQR 4.9-20.9) respectively. A vast majority of the cohort were of Caucasian ancestry (89.1%). Of a total of 561 genes sequenced, there were mutations in 79 genes (14.1%). The mutation frequency was significantly higher in M1PCa compared to M0PCa, 35.7% and 23.3%, respectively (P = <0.001). The median tumor mutational burden was also significantly higher in the samples from M1PCa (2.59 mut/MB) compared to M0PCa (1.96 mut/MB) (P < 0.001). Compared to M0PCa patients, M1PCa patients demonstrated significantly higher rate of genetic mutations; TP53 (38.73% vs. 17.71% P < 0.001), PTEN (25.70% vs. 11.71% P < 0.001), AR (17.25% vs. 1.43% P < 0.001), APC (11.8% vs. 4.43% P < 0.001), TMPRSS2 (31.5% vs. 11.14% P < 0.001), ERG (23.59% vs. 13.13% P < 0.001), FOXA1 (17.43% vs. 6.33% P < 0.001), MYC (8.45% vs. 2.29% P < 0.001), RB1 (10.39% vs. 2.43% P < 0.001) and CDK12 (8.45% vs. 1.31% P < 0.001).  Of the various cellular signaling pathways, the androgen receptor signaling pathway was most often impacted. In the cohort with M1 disease, compared to men without genetic mutations the men with genetic mutations demonstrated worse survival (P = <0.001, log rank test). Compared to castration sensitive M1 patients, AR (57% vs. 4% P < 0.001), TP53 (50.7% vs. 34% P < 0.001), PTEN (35.2% vs. 22.1% P < 0.001), RB1(23.9% vs. 4.75% P < 0.001) were significantly more frequently mutated in castration resistant M1 patients. In contrast, mutations of SPOP (13.3% vs. 7.9% P < 0.001), FOXA1 (17.6% vs. 5.3% P < 0.001) and CDK12 (12% vs. 6.45% P < 0.001) were significantly more frequently found in castration sensitive M1 patients compared to castration resistant patients.

CONCLUSION

Patients with M1PCa demonstrated characteristic genetic mutations compared to M0PCa, which most often influenced androgen receptor signaling and is associated with worse survival. In addition, we identified distinct genetic mutations between castration sensitive and resistant M1PCa. These findings may be used to further our understanding and management of men with PCa.

Genetic mutations in smoking-associated prostate cancer

OBJECTIVES

Tobacco smoking is known to cause cancers potentially predisposed by genetic risks. We compared the frequency of gene mutations using a next generation sequencing database of smokers and nonsmokers with prostate cancer (PCa) to identify subsets of patients with potential genetic risks.

MATERIALS AND METHODS

Data from the American Association for Cancer Research Project Genomics Evidence Neoplasia Information Exchange (GENIE) registry was analyzed. The GENIE registry contains clinically annotated sequenced tumor samples. We included 1832 men with PCa in our cohort, categorized as smokers and nonsmokers, and compared the frequency of mutations (point mutations, copy number variations, and structural variants) of 47 genes with more than 5% mutation rate between the two categories and correlated with overall survival using logistic regression analysis.

RESULTS

Overall, 1007 (55%) patients were nonsmokers, and 825 (45%) were smokers. The mutation frequency was significantly higher in smokers compared to nonsmokers, 47.6% and 41.3%, respectively (p = 0.02). The median tumor mutational burden was also significantly higher in the samples from smokers (3.59 mut/MB) compared to nonsmokers (1.87 mut/MB) (p < 0.001). Patients with a smoking history had a significantly higher frequency of PREX2, PTEN, AGO2, KMT2C, and a lower frequency of adenomatous polyposis coli (APC) and KMT2A mutations than compared to nonsmokers. The overall mortality rate (28.5% vs. 22.8%) was significantly higher among smokers (p = 0.006). On a multivariate logistic regression analysis, the presence of metastatic disease at the time of diagnosis (OR: 2.26, 95% CI: 1.78-2.89, p < 0.001), smoking history (OR: 1.32, 95% CI: 1.05-1.65, p = 0.02), and higher frequency of PTEN somatic gene mutation (OR: 1.89, 95% CI: 1.46-2.45, p < 0.001) were independent predictors of increased overall mortality among patients with PCa. Patients with PTEN mutation had poorer overall survival compared to men without PTEN mutations: 96.00 (95% CI: 65.36-113.98) and 120.00 (95% CI: 115.05-160.00) months, respectively (p < 0.001) irrespective of smoking history although the G129R PTEN mutation was characteristically detected in smokers.

CONCLUSIONS

PCa patients with a tobacco smoking history demonstrated a significantly higher frequency of somatic genetic mutations. Whereas mutations of PREX2, KMT2C, AGO2, and PTEN genes were higher in smokers, the APC and KMT2A mutations were higher in nonsmokers. The PTEN somatic gene mutation was associated with increased overall mortality among patients with PCa irrespective of smoking history. We found that G129R PTEN mutation known to reduce the PTEN phosphatase activity and K267Rfs*9 a frameshift deletion mutation in the C2 domain of PTEN associated with membrane binding exclusively detected in smokers and nonsmokers, respectively. These findings may be used to further our understanding of PCa associated with smoking.

Abstract 2475: Bromodomain inhibitor: MT1 and its potential role in modulation of prostate cancer progression

Bromodomains (BD) are epigenetic readers of histone acetylation involved in chromatin remodeling and transcriptional regulation of protooncogene cellular myelocytomatosis (c- Myc) and other genes. Because c-Myc cannot be directly targeted by small molecular inhibitors due to disordered alpha helical structure, epigenetic targeting of c-Myc by BD inhibitors is an attractive therapeutic strategy for diseases such as prostate cancer (PC) associated with increased c-Myc upregulation with advancing disease. We studied the efficacy of MT1, a novel bivalent BD inhibitor that is 100-fold more potent than the first in class BD inhibitor JQ1, at inhibiting PC growth. We tested the effect on viability by MT-1 on PC cell lines, 3D spheroids derived from clinically annotated drug resistant patient derived xenografts (PDX), mice PDX models and corroborated the molecular mechanism of MT1 down regulation of Myc leading to downstream Myc-dependent up regulation of Protein Kinase D1 (PrKD) substrate phosphorylation by western blot. MT-1 inhibited growth of PC in castration sensitive (LNCaP) and resistant PC cells (PC-3). MT-1 treatment upregulated PrKD expression and phosphorylation of known PrKD substrates: threonine 120 (Thr-120) residues in beta-catenin and the serine 216 in Cell Division Cycle 25 (CDC25C) in PC-3 cells. Moreover, MT-1 was effective in inhibition of 3D spheroids growth at IC 50 between 0.27-0.92µM in Abiraterone, Enzalutamide, Docetaxel, Cabazitaxel metastatic castrate resistant PCa patient-derived tumor 3D spheroids. Additionally, MT1 was effective in inhibiting the tumor growth in PDX mice model. A combined intra-peritoneal administration of MT-1 with another c-Myc inhibitor (3JC48-3), an obligate c-Myc and MYC-associated protein X (MAX) heterodimerization inhibitor, increased the efficacy of inhibiting the PDX growth in mice. This study provides strong pre-clinical in vitro and in vivo evidence for advancing MT- 1 as a novel c-Myc targeting drug in PC. The MT-1 drug development will likely be highly impactful as c-Myc is dysregulated in three fourths of men with advanced PC.

Citation Format: Sanjeev Shukla, Mohammed Al-Toubat, Allison H. Feibus, Ahmed Elshafei, Carlos Riveros, Nathalie Meurice, Justyna Gleba, Jonathan Chardon-Robles, Adam M. Kase, John A. Copland III, Joachim L. Petit, Teruko Osumi, K.C. Balaji. Bromodomain inhibitor: MT1 and its potential role in modulation of prostate cancer progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2475.

Magnetic resonance imaging radiomic features for recurrent prostate cancer following proton radiation therapy-A pilot study

OBJECTIVE

The role of multiparametric MRI (mp-MRI) for postproton radiation evaluation is unclear. In this pilot study, we characterize the mp-MRI features using the Prostate Imaging-Reporting and Data System (PI-RADS) for recurrent prostate cancer (PCa) following proton radiation therapy.

METHODS

After obtaining IRB approval, we identified 163 consecutive cases who underwent MRI-fusion prostate biopsy at our institution from November 2017 to May 2020. This study evaluated patients with prostate cancer (PCa) with biochemical recurrence following proton radiation. Patients were excluded if they had grossly metastatic disease, metal fragments, implanted devices, or with surgically removed prostates. The mpMRI studies were reviewed in depth and scored by 2 fellowship-trained radiologists. Following MRI-fusion biopsy of lesions of interest (LOI), slides were read by fellowship-trained pathologists.

RESULTS

We found 14 patients with 16 lesions who met the study inclusion criteria. The median age was 69 years (range 57-79) and median time to biochemical recurrence was 7.3 years (range 3-13). On post-treatment imaging, decreases in prostate size and diffusely decreased T2 signal intensity were observed, making the use of apparent diffusion coefficient (ADC) and early enhancement at dynamic contrast enhanced (DCE) imaging often necessary for diagnosis of disease recurrence. We identified a total of 16 lesions with PIRADS scores of 3 or higher. Of these lesions, there were 5 PIRADS 3 lesions (4/5 (80%) without prostate cancer), 7 PIRADS 4-5 lesions (6 (86%) had high risk Pca), and 4 lesions with unassigned PIRADS scores (100% had high risk cancers). Among the MRI variables, diffusion weighted imaging (DWI) heterogeneity had the strongest association with recurrence of PCa (P < 0.001).

CONCLUSIONS

Results of our pilot study showed that the PIRADS scoring system in the postproton radiation therapy setting has some correlations with prostate cancer recurrence; However, the clinical value of these findings are unclear. While definitive PIRADS categorization of lesions demonstrated expected frequency of cancer consistent with the scoring system, all unassigned lesions also harbored malignancy suggesting a cautious approach to PIRADS scoring system in postproton radiation setting. The findings from this study may be validated using a larger cohort.

57. clinical Characteristics and Outcomes of Patients Hospitalized with COVID-19 in New Orleans, LA: A Cohort Study

Background

In Louisiana, deaths related to COVID-19 have disproportionately occurred in Black persons. Granular data are needed to better understand inequities and develop prevention strategies to mitigate further impact on Black communities.

Methods

We conducted a retrospective cohort study of patients admitted to an urban safety net hospital in New Orleans, LA with reactive SARS-CoV-2 testing from March 9–31, 2020. Clinical characteristics and outcomes of Black and other racial/ethnic group patients were compared using Wilcoxon rank-sum test and Fisher’s exact tests. We examined Day-14 status using an ordinal scale to assess race and outcome.

Table 1. Demographics and Comorbidities by Race for Patients Hospitalized with COVID-19

Results

This study included 249 patients. Median age was 59, 44% were male, 86% were age ≥65 years or had ≥1 comorbidity. Overall, 87% were Black, relative to 55% Black patients typically hospitalized at our center. Black patients had longer symptom duration at presentation (6.41 versus 5.88 days, p=0.05), and were more likely to have asthma (p=0.008), but less likely to have dementia (p=0.002). There were no racial differences in initial respiratory status or laboratory values other than higher initial LDH in Black patients. Patient age and initial oxygen requirement, but not race (adjusted proportional odds ratio = 0.92, 95%CI: 0.70–1.20), were associated with worse Day-14 outcomes.

Figure 1: Admissions over time by Race

Conclusion

Our results demonstrate minor racial differences in comorbidities or disease severity at presentation, and Day-14 outcomes were not different between groups. However, Black patients were disproportionately represented in hospitalizations, suggesting that prevention efforts should include strategies to limit SARS-CoV-2 exposures in Black communities as one step towards reducing racial inequities related to COVID-19.

Figure 3a: Logistic Regression for Initial Oxygen Requirement

Disclosures

Meredith E. Clement, MD, FHI360 (Consultant)Gilead (Research Grant or Support)Janssen (Scientific Research Study Investigator)

Prospective Observational Study of a Racially Diverse Group of Men on Active Surveillance for Prostate Cancer

OBJECTIVE

To evaluate the risk upgrading of active surveillance (AS), we reviewed the outcomes of African American men (AA) after electing AS. AS is the standard of care for men with low-grade prostate cancer (PCa). AA are known to have more advanced PCa features and are more likely to die from PCa, thus subsequent disease progression for AA on AS is unclear.

METHODS

A prospectively maintained AS database from the Southeast Louisiana Veterans Administration Medical Center, New Orleans, Lousiana was queried. We identified men with low- and very low-risk PCa (Gleason 3 + 3, PSA <10, ≤CT2a) who had undergone at least 2 prostate biopsies, including initial diagnostic and subsequent confirmatory prostate biopsies. Descriptive and comparative statistical analysis was performed using R version 3.5.1.

RESULTS

From a total of 274 men on AS (70% AA), 158 men met inclusion criteria (104 AA [66%]). All patients underwent at least 2 biopsies, and 29% underwent 3 or more biopsies. The median follow-up was 2.7 years. At 3 years on AS protocol, 57% AA and 61% Caucasians demonstrated no evidence of upgrading or treatment. No significant difference was observed between upgrading or progression to treatment when comparing racial groups. Seven (4%) patients in this cohort died from non PCa-specific causes, but no patients demonstrated metastasis or death from PCa over the course of study.

CONCLUSION

AA men with low-risk PCa can be safely followed with the same AS protocol as non-AA men. Further analysis with longer follow up is ongoing.

Clinical Characteristics and Outcomes Based on Race of Hospitalized Patients With COVID-19 in a New Orleans Cohort

Background

In Louisiana, deaths related to COVID-19 have disproportionately occurred in Black persons. Granular data are needed to better understand inequities and develop prevention strategies to mitigate further impact on Black communities.

Methods

We conducted a retrospective study of patients admitted to an urban safety net hospital in New Orleans, Louisiana, with reactive SARS-CoV-2 testing from March 9 to 31, 2020. Clinical characteristics of Black and other racial/ethnic group patients were compared using Wilcoxon rank-sum test and Fisher exact tests. The relationship between race and outcome was assessed using day 14 status on an ordinal scale.

Results

This study included 249 patients. The median age was 59, 44% were male, and 86% were age ≥65 years or had ≥1 comorbidity. Overall, 87% were Black, relative to 55% Black patients typically hospitalized at our center. Black patients had longer symptom duration at presentation (6.41 vs 5.88 days; P = .05) and were more likely to have asthma (P = .008) but less likely to have dementia (P = .002). There were no racial differences in initial respiratory status or laboratory values except for higher lactate dehydrogenase in Black patients. Patient age and initial oxygen requirement, but not race (adjusted proportional odds ratio, 0.92; 95% CI, 0.70–1.20), were associated with worse day 14 outcomes.

Conclusions

Our results demonstrate minor racial differences in comorbidities or disease severity at presentation, and day 14 outcomes were not different between groups. However, Black patients were disproportionately represented in hospitalizations, suggesting that prevention efforts should include strategies to limit SARS-CoV-2 exposures and transmission in Black communities as one step toward reducing COVID-19-related racial inequities.

Liver metastases in mCRPC patients post-therapy with abiraterone (Abi) and/or abiraterone/enzalutamide (Enza)

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Background: Liver metastases (mets) are a particularly poor prognostic group among mCRPC patients. The objective of this study is to characterize mCRPC patients who have had treatment with Abi or Enza to identify risk factors that may be associated with subsequent development of liver mets. Methods: A sample of 67 patients (n = 17 liver mets and 50 non-liver met patients matched by treatment history) seen at Tulane Cancer Center were selected for analysis. All patients had prior Abi and or Abi/Enza. Race, age at PCa diagnosis and Gleason Score at PCa diagnosis were assessed. For patients with liver mets, total liver metastatic volume was measured using CT scans and correlated against PSA, LDH and AST values at the time of the scan. Wilcoxon rank sum tests were run analyzing PSA, LDH and AST at the start of Abi treatment, end of Abi treatment as well the duration of Abi treatment, and the nadir PSA for these patients. Results: Patients were predominantly Caucasian, had a median Gleason Score of 8 at diagnosis and were at a median age of 57 for those with liver mets and 62 for non-liver met at PCa diagnosis. Pearson correlation analysis of the total liver lesion volume and lab values revealed a significant correlation for LDH (R = 0.491, < 0.01) and AST (R = 0.368, p < 0.05), but not for PSA. Further evaluation of PSA and AST values at the start and end of Abi treatment as well as at nadir PSA revealed no statistically significant differences between liver met patients and non-liver met patients. However, there was a significant difference (p = 0.015) between LDH levels at the end of Abi treatment with a median of 347 U/L for liver met and 238 U/L for non-liver met patients. Conclusions: LDH and AST levels correlate with extent of liver metastases. Additionally, elevated LDH at the end of Abi treatment is indicative of an increased risk for developing liver metastases. Larger sample sizes and molecular characterization of these tumors are required to gain more insights into this important patient population.

Racial variations in upgraded gleason scores of active surveillance candidates

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Background: Currently, active surveillance is an appropriate option for patients who have low risk PCa as determined by the NCCN as Gleason Score (GS) ≤ 6 and a PSA <10. Methods: Following IRB approval, we determined that 141 men from our database had low risk PCa and were eligible for AS, but underwent radical prostatectomy (RP). We performed a retrospective review of these patients examining GS upon RP. Disease upgrading on RP was considered Gleason score ≥ 7. A two-tailed t-test was performed to examine whether African American (AA) patients had greater incidence of upgrading on RP than non-African American patients. Results: Of the 141 patients identified (36 AA, 105 non-AA) there were no significant differences in age at RP (59 AA, 59 non-AA), median PSA (5.5 ng/dL AA, 5.4 ng/dL non-AA), and number of positive cores (3 AA, 3 non-AA) at biopsy when stratified by race. A total of 85 patients (19 AA, 66 non-AA) were found to have an upgraded GS at the time of RP; again without significant difference with respect to age (60 AA, 61 non-AA), serum PSA (5.3 AA, 5.35 non-AA), total cores taken at biopsy (12 AA, 12 non-AA) and median positive cores (3.5 AA, 3 non-AA). Of the 85 patients upgraded, 66 (12 AA, 54 non-AA) were 3+4 and the remainder were ≥ 4+3. There was no significant racial variation for patients upgraded to Gleason 3+4 (p>0.05). Next we reviewed the presence of tertiary pattern 5 within these 3+4 patients and found it present in 1 patient who was AA. For the 19 patients with ≥ 4+3 upgrading, with respect to race (7 AA, 12 non-AA, p = .08) there were no significant differences in age, serum PSA, median positive and total cores taken at biopsy. However, when comparing these 19 upgraded ≥ 4+3 patients to the total cohort, they had a higher median serum PSA (6.16 ng/dLvs 5.4 ng/dL) and higher positive cores (4 vs 3) on biopsy. For these 19 patients, upgrading resulted in reclassification from low to high-grade (GS ≥ 8) PCa in 7 patients. Conclusions: African American patients with low risk PCa have do not have an increased risk of significant upgrading at RP when compared with other races, and further investigation is needed to identify factors that contribute to upgrading.

Racial variation in the reliability of prostate cancer indicators in men undergoing subsequent prostate biopsy

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Background: Many men with an initial negative prostate biopsy have a persistently elevated prostate specific antigen (PSA) prompting physicians to perform repeat biopsies. African American men (AA) are at particular risk as they have a greater prostate cancer (PCa) incidence and mortality, yet traditional PSA testing may be less reliable in this cohort. We sought to determine the predictors of PCa and PCa severity in a racially diverse population on subsequent biopsy following an initial benign biopsy. Methods: Upon receiving Institutional Review Board approval, a retrospective analysis was performed on men with repeat prostate biopsies at Tulane Medical Center and Southeast Louisiana Veterans Health Care Services in New Orleans, Louisiana from 2003-2015. Inclusion criteria included patients with a benign initial prostate biopsy and underwent subsequent repeat prostate biopsy within 5 years. Race, age, serum PSA, PSA density (PSAD), and prostate volume by transrectal ultrasound (TRUS) were evaluated to determine if they correlate with the presence and severity of PCa. Aggressive PCa was defined as Gleason score >6. Results: A total of 209 men were included; 127 (61%) were AA, and 82 (39%) were Caucasian American men (CA). The two groups were similar with respect to PSA, PSAD, and TRUS. More AA (25.2% vs. 17.1%) had a repeat biopsy showing any PCa. Of those with PCa, 28.1% of AA and 28.6% of CA had aggressive PCa. PSAD positively correlated with any PCa (p=.015). TRUS negatively correlated with any PCa (p=.008). PSA levels (p<.001) and PSAD (p<.001) positively correlated with aggressive PCa in CA but not in AA. Conclusions: The goal of prostate biopsy particularly for those with a prior negative biopsy is to detect aggressive PCa. PSA and PSAD positively correlated with finding any PCa in both AA and CA but not with aggressive PCa in AA. PSA and PSAD are less accurate predictors of aggressive PCa in AA, and novel biomarkers are needed. [Table: see text]

Baseline differences in characteristics of a racially diverse group of men electing active surveillance

103

Background: To date, large populations of men from European ancestry have been prospectively evaluated on Active Surveillance (AS), a strategy reserved for low risk prostate cancer (PCa). African Americans (AA) deemed to be candidates for AS have yet to be fully characterized. We sought to determine the similarities and differences of our AS cohort stratified by race. Methods: We identified 308 men from our multi-institutional, prospective AS database were analyzed. Inclusion criteria was PSA < 20ng/mL, Gleason score ≤ 7, and clinical stage ≤ T2a. Men who sought treatment for their PCa or refused subsequent imaging and biopsy were excluded. Univariate analysis was done to analyze racial differences in demographic, clinical and pathologic variables. Results: We identified 308 men, 131 (43%) AA and 177 nonAA (57%). The groups were not significantly different with respect to age; 65 years, BMI 28.4, family history of PCa (22%), prior negative biopsy (21%) and clinical staging (87% T1c). Median follow-up is 25 months (IQR 12-44). Significant differences between the AA and nonAA cohorts did exist at baseline with respect to overall health, suggesting AA having worse overall health. More AA had diabetes (29 vs 14%; p = .03), were smokers (55 vs 29%; p < .01), cardiovascular disease (21 vs 9%) and erectile dysfunction (43 vs 18%; p < .01). Social characteristics also differed within the groups, with AA less likely to be married (47 vs 51%; p = .01). Despite a lack of difference with respect to biopsy Gleason score, AA had higher PSA (5.7 vs 5.0 ng/mL; p = 0.02), lower testosterone levels (250 vs 334 ng/dL; p = 0.05), greater PSA density (0.15 vs 0.12; p < 0.01), and greater linear length of cancer per biopsy core (16 vs 13mm; p < 0.01) at time of diagnosis and initiation of AS. Conclusions: Within our AS cohort, AA have worse overall health and more aggressive PCa features despite meeting inclusion criteria and selecting AS. Further prospective study is needed to determine how these competing factors may impact long term outcomes.

Early assessment of PSA response in patients with mCRPC treated with enzalutamide and abiraterone

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Background: Abiraterone (Abi) and enzaleutamide (Enza) are first-line agents for the treatment of metastatic castrate-resistant prostate cancer (mCRPC). Primary resistance is well-documented, but little data exists for rapid treatment responders. This study intended to further characterize patients with early prostate-specific antigen (PSA) decline. Methods: A single-institution retrospective review was performed on 123 mCRPC patients treated with Abi and/or Enza. PSA was recorded every 4 weeks for the duration of treatment. The primary endpoint was to describe PSA response, including sensitivities and specificities, as a predictor of later treatment response (defined as ≥50% decrease in PSA from baseline). Additional clinical covariates were also evaluated as treatment-response predictors. Results: A PSA response to Abi was achieved in 52/123 (42%) of patients. Median time to PSA nadir was 37 days. 30/52 (58%) patients responded to the drug within 4 weeks. Median length of time on drug was 110 days. A PSA response to Enza was achieved in 21/123 (17%) of patients. Median time to PSA nadir was 140 days. 18/21 (86%) of patients responded to the drug within 4 weeks. Median length of time on drug was 161 days. Conclusions: Percentage of PSA decline and time to drug response for Enza and Abi are important variables that can serve as reliable way for clinicians to predict long-term PSA response. It is vital to make appropriate treatment modifications for patients that do not display early PSA response. [Table: see text]

Treatment sequencing of abiraterone and enzalutamide in patients with mCRPC

233

Background: Abiraterone (Abi) and Enzalutamide (Enza) are among the treatment modalities available for treating metastatic castrate-resistant prostate cancer (mCRPC). This study aimed to analyze the efficacy of Abi and Enza as direct sequential treatments for patients with mCRPC. Methods: A single institution retrospective review was performed on 66 patients, in which 52 (79%) of the patients received Enza following Abi. The primary outcome measure was PSA response (50% PSA decline). Patients treated with taxanes between Abi and Enza were excluded from these analyses. Results: In patients treated first with Abi and second with Enza (n = 52), 35/52 (67%) responded initially to Abi. Following PSA progression or lack of initial response, all 52 patients were then treated with Enza, and 15/52 (29%) responded. Of the 17 patients that did not initially respond to Abi, 9 (53%) patients had a PSA response to Enza, in which 5/9 had a PSA decline ≥ 50%. 14 patients had a PSA decline ≥ 50% on initial Abi only (no PSA declines at all were noted post-Abi) and 3/14 responded to Enza. The median duration on the 1st drug was 294 days; median duration on the 2nd drug was 89 days. Conclusions: Additional investigation is needed for clinicians to understand better the cross resistance of Abi and Enza in mCRPC patients. [Table: see text]

Utility of PCA3 and TMPRSS2: ERG urinary biomarkers to predict pathologic outcomes in African American men undergoing radical prostatectomy

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Background: Tremendous disparity exists between preoperative characteristics and pathologic outcomes in men electing radical prostatectomy (RP) for localized prostate cancer (PCa). We sought to determine the performance characteristics of urinary PCA3 andTMPRSS2:ERG (T2:ERG) to predict pathologic outcomes in a racially diverse group of men undergoing RP. Methods: Following IRB approval, post digital rectal exam (DRE) urine was prospectively collected in consecutive patients with known PCa prior to RP. PCA3 and T2:ERG RNA copies were quantified and normalized to PSA mRNA copies using the Progensa assay (Hologic, San Diego, CA). Nonparametric Mann-Whitney U tests were performed to determine the ability of PCA3 and T2:ERG to predict higher risk PCa and notable disease features. Results: The cohort consisted of 214 men with PCa who underwent RP, and 89 men (42%) were African American (AA). The men in the cohort generally had higher risk disease, with 75% having AUA risk stratification of intermediate/high-risk PCa. PCA3 discriminated between biopsy low- and intermediate/high-grade Gleason Score (p = .005) and pathologic low- and intermediate/high-grade Gleason Score (p = 0.001). For men with low-risk PCa, PCA3 also predicted Gleason Score upgrading from biopsy to prostatectomy specimen (p = 0.003). PCA3 could not predict the presence of perineural invasion, lymph node positivity, seminal vesical invasion, positive surgical margins or extraprostatic extension. When stratified by race, within the AA cohort, T2:ERG did predict upgrading from Gleason 6 disease at the time of biopsy to higher grade pathology at RP (p = 0.016). However, T2:ERG was not predictive for the overall cohort, nor was it predictive for any of the disease features found to be significant with PCA3. Conclusions: In a racially-diverse group of men undergoing RP, PCA3 and T2:ERG urinary assays have limited ability to characterize aggressive pathologic features at the time of RP regardless of race.

Outcomes of men who underwent treatment for prostate cancer from a prospective follow up of a racially diverse, multi-institutional active surveillance cohort

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Background: Active surveillance (AS) is an increasingly accepted alternative to treatment for low-grade prostate cancer (PCa). However, it remains unclear what factors may predict which patients will upgrade to a higher grade cancer. We sought to analyze the characteristics at time of diagnosis and outcomes of those men in our racially diverse AS cohort who underwent treatment for PCa. Methods: Men from our AS database were analyzed. Inclusion criteria was PSA < 20 ng/mL, Gleason Score ≤ 7, and clinical stage ≤ T2a. Men who elected active treatment for their PCa at diagnosis or refused subsequent imaging and biopsy were excluded from this cohort. Univariate analysis was done to compare the clinical variables of the treatment group with the entire cohort. Results: We identified 56 men who were treated for PCa from the 308 men currently enrolled in our AS cohort. All 56 men in the treatment group had low risk PCa at diagnosis and initiation of AS. At diagnosis, the treatment group was not significantly different in comparison with our entire cohort with respect to age, BMI, family history of PCa, PSA at diagnosis, prior negative biopsy, TRUS volume, PSAD, smoking status and clinical staging. However the eventual treatment group did differ at diagnosis with respect to greater linear length of cancer per core (p < 0.01), greater % involvement of disease (p = 0.03), and greater number of total cores at time of diagnosis (p = 0.04). The men in this group underwent treatment for PCa for the following reasons: 36 for Gleason Score upgrading, 5 due to increased volume of disease, 6 due to rising PSA, 1 due to MRI findings, 1 due to rising PSA on Avodart and 7 elected treatment despite no significant changes in disease. 31 of the men had RARPs, 17 XRT, 4 had XRT + ADT, 3 had Brachytherapy, and 1 with XRT + salvage RP. Conclusions: Within our prospectively enrolled racially diverse AS cohort, the patients who underwent treatment for PCa had clinical factors that differed in comparison to the whole cohort. Further prospective study is needed to determine how these factors may ultimately impact long term outcomes.

Racial variation in prostate needle biopsy templates directed anterior to the peripheral zone

OBJECTIVES

African Americans (AA) have been reported to have both increased incidence and increased aggressiveness of prostate cancer (PCa) located anterior to the peripheral zone (APZ). We sought to evaluate the utility of prostate biopsies directed toward the APZ in a predominantly AA cohort.

METHODS AND MATERIALS

We reviewed all patients with PCa found on biopsy schema that included needle biopsies directed at both the peripheral zone (PZ) and APZ from 2010 to 2014. Self-identified race was recorded for all patients. To evaluate the reliability of APZ-directed prostate biopsies, we performed pathologic secondary review of 25 radical prostatectomy specimens. A series of the Mann-Whitney U and Chi-square tests were used to compare variables.

RESULTS

We identified 398 men, of which 277 (70%) were AA. Compared with non-AA, AA had more National Comprehensive Cancer Network-defined intermediate or high-risk (50% vs. 39%, P = 0.25) PCa. Most patients had PCa limited to the PZ only (n = 190) or in both the PZ and APZ (n = 191). For 17 patients (4%), PCa was limited only to the APZ core(s), 14 (5%) AA vs. 3 (2%) non-AA (P = 0.24). Most of these 17 patients (n = 14, 82%) had Gleason 6 disease. Patients with PCa in both the PZ and APZ had higher serum prostate-specific antigen, prostate-specific antigen density, volume of disease, and increased grade and National Comprehensive Cancer Network category (all P<0.01). Of these patients, there were no differences in race (AA = 135, 71% vs. non-AA = 56, 29%; P = 0.48). In only 21 men (11%), without racial variation, APZ tumor grade was greater than PZ. Radical prostatectomy and APZ-directed biopsies demonstrated a concordance rate of 80% (20/25), false positive rate of 8% (2/25), and false negative rate of 12% (3/25).

CONCLUSIONS

APZ-directed prostate biopsies are rarely the sole location of PCa and do not show a clear racial predilection. In those men with PCa identified in both regions, the APZ biopsy did not frequently change treatment recommendations. Biopsies directed at the APZ are not of greater benefit to AA than non-AA.

Clinical Use of PCA3 and TMPRSS2:ERG Urinary Biomarkers in African-American Men Undergoing Prostate Biopsy

PURPOSE

Prostate specific antigen has decreased performance characteristics for the detection of prostate cancer in African-American men. We evaluated urinary PCA3 and TMPRSS2:ERG in a racially diverse group of men.

MATERIALS AND METHODS

After institutional review board approval, post-examination urine was prospectively collected before prostate biopsy. PCA3 and TMPRSS2:ERG RNA copies were quantified using transcription mediated amplification assays (Hologic, San Diego, California). Prediction models were created using standard of care variables (age, race, family history, prior biopsy, abnormal digital rectal examination) plus prostate specific antigen. Decision curve analysis was performed to compare the net benefit of PCA3 and TMPRSS2:ERG.

RESULTS

Of 304 patients 182 (60%) were African-American and 139 (46%) were diagnosed with prostate cancer (69% African-American). PCA3 and TMPRSS2:ERG scores were greater in men with prostate cancer, 3 or more cores, 33.3% or more cores, greater than 50% involvement of greatest biopsy core and Epstein significant prostate cancer (p <0.01). PCA3 added to the standard of care plus prostate specific antigen model for the detection of any prostate cancer in the overall cohort (0.747 vs 0.677, p <0.0001) in African-American men only (0.711 vs 0.638, p=0.0002) and nonAfrican-American men (0.781 vs 0.732, p=0.0016). PCA3 added to the model for the prediction of high grade prostate cancer for the overall cohort (0.804 vs 0.78, p=0.0002) and African-American men only (0.759 vs 0.717, p=0.0003) but not nonAfrican-American men. Decision curve analysis demonstrated improvement with the addition of PCA3. For African-American men TMPRSS2:ERG did not improve concordance statistics for the detection of prostate cancer.

CONCLUSIONS

For African-American men urinary PCA3 improves the ability to predict the presence of any and high grade prostate cancer. However, the TMPRSS2:ERG urinary assay does not add significantly to standard tools.

Evaluating abiraterone responses in African Americans with metastatic CRPC

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Background: A disparity between African American (AA) and other racial groups is documented in prostate cancer incidence and mortality. For metastatic CRPC, abiraterone (Abi) showed improvement in overall survival and gained FDA approval. However, Phase III trials enrolled mostly Caucasian (CA) patients. Documentation of Abi response rates in AA men is scant. Further characterization of Abi responses in AA men was the objective of this study. Methods: Age at diagnosis, prior enzalutamide (Enza) and/or docetaxel (Doc), and duration of Abi treatment were assessed. Baseline values at Abi initiation for alkaline phosphatase (ALP), hemoglobin (Hgb), and lactate dehydrogenase (LDH) were recorded. PSA values at baseline and throughout treatment were also logged. The velocity of PSA decline was determined by the PSA half-life (PSAHL) based on time to nadir. PCWG2 criteria were used to define PSA response and progression. Results: This was a single institution, retrospective cohort of 103 patients with mCRPC treated with Abi (n = 24 AA; n = 79 CA). Median age at diagnosis was 61.8 years and 62.4 years for AA and CA respectively. Prior Enza/Doc was 4.2%/33.3% for AA and 6.3%/29.1% for CA. Median duration of Abi therapy in AA was 207 days and 253 days for CA; neither median age or duration were statistically distinct. Median AA baseline ALP, Hgb, LDH, and PSA was 136 (range (r) = 59-653), 11.8 (r = 8.9-15.4), 256 (r = 157-401), and 59.9 (r = 4.8-1658) respectively. Median CA baseline ALP, Hgb, LDH, and PSA were 88 (r = 51-1600), 12.4 (r = 8.4-15.0), 204 (r = 100-528), and 40.6 (r = 2.5-2890) respectively. The difference in baseline lab values between AA and CA were insignificant. No statistical difference was seen in median PSAHL (AA = 55 days; CA = 64 days), or PSA decline of > 30% (AA = 50%; CA = 52%), > 50% (AA = 46%; CA = 39%), or > 90% (AA = 21%; CA = 14%). Finally, neither the median time to nadir (AA = 119 days; CA = 137 days) or progression (AA = 157 days; CA = 131 days) were significantly different. Conclusions: Comparison between AA men and CA men in mCRPC patients being treated with Abi showed no statistical difference in response rates, duration of response, or time to progression. Prospective, multi-institutional studies are needed to further assess these findings.

Race, inflammation, and prostate cancer: A comparison of African Americans and Caucasians

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Background: African-Americans (AA) have the highest rate of prostate cancer (PCa) incidence and mortality. Studies have shown higher rates of chronic prostate inflammation in AAs compared to Caucasians (CA). In order to better understand racial disparity in PCa and chronic inflammation (CI), this study examined the effects of race and CI on clinical parameters among PCa patients. Methods: This retrospective study sample consisted of 61 AA and 52 CA PCa patients who underwent radical prostatectomies (RP) at Tulane Hospital between 2013 and 2015. Clinical data was extracted from biopsy and RP pathology reports. The study examined the relationship between CI, race, percent of positive cores, extra-prostatic extension, PSA, PSA density, urinary PCA3 and TMPRSS2, and prostate size (g). Pearson’s chi-square, Fisher’s exact, and Kruskal-Wallis tests were used to analyze categorical, non-continuous data; ANOVA tests were used to analyze continuous data. Differences between biopsy and surgical/pathologic Gleason scores and clinical/pathological stages were also assessed. Results: 94 patients (52 AAs and 42 CAs) had CI to some degree and 19 did not (9 AAs and 10 CAs). There was no difference in rate of CI between AA and CA patients (P = 0.526). Among all patients sampled, AAs had higher percentages of positive cores (P = 0.005), PCA3 copy levels (P =0.004), and PCA3 scores (P <0.001), lower TMPRSS2 scores (P =0.039), and were more likely to have “high” or “intermediate” NCCN risk strata (P =0.010). Among patients with CI, AAs were more likely than CAs to have extra-prostatic extension (P =0.026) and less likely to have undergone a prior prostate biopsy (P =0.043). Patients without CI were more likely than patients with CI to have positive tumor margins (P =0.035) and SV invasion (P =0.013). There were no significant relationships between race and CI, and changes in either total Gleason score or stage from biopsy to RP. Conclusions: This study showed that AAs and patients without CI had more advanced forms of PCa (possibly due to PSA detection biases). Findings did not reveal any significant link between race and CI. Larger studies are needed to confirm these results and better understand the relationship between race, CI, and PCa.

Racial variation in the outcome of subsequent prostate biopsies in men with an initial diagnosis of atypical small acinar proliferation (ASAP)

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Background: African Americans (AA) are known to have more aggressive prostate cancer (PCa) and a greater probability of death from PCa. We sought to determine predictors of subsequent detection and risk stratification of PCa in a racially diverse group of men who presented with atypical small acinar proliferation (ASAP) on initial prostate biopsy. Methods: Upon receiving IRB approval, a retrospective analysis was performed on men from the Southeast Louisiana Veterans Health Care System and Tulane University Medical Center who presented with ASAP on initial prostate biopsy and subsequently received confirmatory prostate biopsies from September 2000 through July 2015. Confirmatory biopsy with a greater than 3-year interval from the initial were excluded. Self-identified race, age, body mass index (BMI), transrectal ultrasound (TRUS) volume, serum prostate-specific antigen (PSA), PSA velocity (PSAV), PSA density (PSAD), and elapsed time between biopsies were evaluated to determine if they were predictors of subsequent PCa diagnosis in patients with an initial finding of ASAP. Results: Of the 106 men in the analysis cohort, 75 (71%) were AA and 31 (29%) were not African American (non-AA). AA had higher PSA, PSAV, and PSAD (all p < 0.05). Age, BMI and TRUS volume were not statistically different between AA and non-AA. PCa was diagnosed in subsequent biopsy in 42 (40%) patients without significant racial variation; 30 (40%) AA vs 12 (39%) non-AA. Of the 42 men with PCa, 25 (24%) met Epstein pathological criteria for significant disease, although without racial variation; 18 (24%) AA vs 7 (23%) Non-AA. Only 10 (9%) men, again without racial variation, had any component of Gleason 4; 7 (9%) AA vs 3 (10%) non-AA. On multivariate analysis, increasing age, PSA and PSAD were significant predictors of cancer on repeat biopsy while race, BMI, TRUS volume and number of cores with ASAP were not. Conclusions: AA diagnosed with ASAP on initial prostate biopsy do not have increased risk of PCa on confirmatory biopsy compared to non-AA. Regardless of race, most cancers were low grade and lower volume, and AA with ASAP should be managed in a similar manner to non-AA with ASAP.

Sequencing of treatments in metastatic CRPC for patients who have completed all therapeutic interventions

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Background: The current treatment paradigm for metastatic, castrate-resistant prostate cancer (mCRPC) has rapidly changed and six therapies [abiraterone (Abi), enzalutamide (Enza), docetaxel (Doc), cabazitaxel (Cab), radium-223 (Ra-223), and sipuleucel-T (Sip-T)] have now been proven to prolong overall survival. Though sequential therapy is the norm, few studies have reported on the variety and prevalence of these agents over the course of patient's lifetime. Herein, we sought to describe the temporal frequencies of mCRPC therapies in patients who completed all of their therapies. Methods: Retrospective chart reviews were conducted on 119 patients who died from mCRPC at Tulane Cancer Center from 2008-2015 (thus completing all possible therapies). Many patients were not treated with multiple life-prolonging therapies given the timing of their death. Post-mCRPC therapies were longitudinally sequenced and a frequency table was generated for first, second, third, etc. line of therapies. Results: Median duration from initial androgen deprivation therapy to mCRPC was 29 months (range: 0-252) and 34.4% of the cohort presented with distant metastatic disease (M1) at diagnosis. The most common front line mCRPC therapies were nilutamide, Doc, Abi, and ketoconazole (Keto) in that order. Keto, Doc, dexamethasone, and Abi were the most common second line therapies. Abi, Doc, DES, and Cab were the most prevalent third line therapies. Doc, Abi, Cab, and Ra-223 were most common fourth line therapies. The median overall survival for our cohort was 69 months (range: 5-270 months) from initial diagnosis. Conclusions: This retrospective analysis provides a temporal snapshot of the timing and frequency of treatments for men dying from mCRPC from 2008-2015. More recent patients are likely to have greater access to contemporary therapies.

Pathologic upgrading on confirmatory biopsy in a racially diverse group of men on active surveillance for prostate cancer

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Background: To evaluate the clinical variables associated with upgrading at confirmatory biopsy among a racially-diverse group of men with prostate cancer (PCa) who elect Active Surveillance (AS). Methods: Following IRB approval, of the more than 260 men from our multi-institutional prospective AS database we identified 140 that had undergone at least 1 confirmatory biopsy since their initial diagnosis. Patients whose diagnosis was made on TURP, had any Gleason 4 on their initial biopsy or whose initial and confirmatory biopsy were more than 2 years apart were excluded. The analysis cohort included 121 men who had Gleason Score ≤ 6, clinical stage ≤ T2a and PSA ≤ 20 ng/mL. Disease upgrading on confirmatory biopsy was Gleason score ≥ 7. Multiple variables were examined as univariate and MV predictors of upgrading. Results: We identified 121 men who fit inclusion criteria, 55 (45%) African Americans (AA) and 66 non-AA (55%) with a median follow-up of 22 months. The median age was 66, median number of biopsy cores taken at diagnostic biopsy was 12 and median time interval between diagnostic and confirmatory biopsy was 12 months. On confirmatory biopsy, no evidence of disease was noted for 51 (42%) men (26 AA, 25 non-AA), 48 (40%) men (18, AA, 30 non-AA) had findings consistent with their initial biopsy and 22 men (11 AA, 11 non-AA) experienced upgrading at repeat biopsy. Of the 22 (18%) men who were upgraded, 18 (8 AA, 10 non-AA) upgraded to a Gleason score of 7, 3 (2 AA, 1 non-AA) were upgraded to a Gleason score of 8 and 1 (AA) had a Gleason score of 9. In univariate analysis AA race was associated with a greater number of positive cores (p = 0.04) and greater total prostate volume (p = 0.03) at confirmatory biopsy. Multivariate analysis was performed and none of the clinical variables examined (race, age, BMI, PSA, volume, PSAD, number of positive cores, total number of cores, percentage of positive cores, time between biopsies) were associated with upgrading on repeat biopsy. Conclusions: Our findings suggest that race is not associated with an increased risk of upgrading at confirmatory biopsy. AA with low-risk PCa are reasonable candidates for inclusion in most AS protocols and should not be excluded based on race alone.

Utility of PCA3 and TMPRSS2:ERG urinary biomarkers in African American men undergoing prostate biopsy

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Background: To determine the performance characteristics of urinary PCA3 andTMPRSS2:ERG (T2:ERG) in a racially diverse group of men. Methods: Following IRB approval, from 2013-2015, post digital rectal exam (DRE) urine was prospectively collected in patients without known prostate cancer (PCa), prior to biopsy. PCA3 and T2:ERG RNA copies were quantified and normalized to PSA mRNA copies using Progensa assay (Hologic, San Diego, CA). Prediction models for PCa and high-grade PCa were created using standard of care (SOC) variables (age, race, family history of PCa, prior prostate biopsy and abnormal DRE) plus PSA. Decision Curve Analysis was performed to compare the net benefit of using SOC, plus PSA, with the addition of PCA3 and T2:ERG. Results: Of 304 patients, 182 (60%) were AA; 139(46%) were diagnosed with PCa (69% AA). PCA3 and T2:ERG scores were greater in men with PCa, ≥ 3 cores, ≥ 33.3% cores, > 50% involvement of greatest biopsy core and Epstein significant PCa (p-values < 0.04). PCA3 added to the SOC plus PSA model for the detection of any PCa in the overall cohort (0.747 vs 0.677; p < 0.0001), in AA only (0.711 vs 0.638; p = 0.0002) and non-AA (0.781 vs 0.732; p = 0.0016). PCA3 added to the model for the prediction of high-grade PCa for the overall cohort (0.804 vs 0.78; p = 0.0002) and AA only (0.759 vs 0.717; p = 0.0003) but not non-AA. Decision curve analysis demonstrated significant net benefit with the addition of PCA3 compared with SOC plus PSA. For AA, T2:ERG did not improve concordance statistics for the detection any or high-grade PCa. Conclusions: For AA, urinary PCA3 improves the ability to predict the presence of any and high-grade PCa. However for this population, T2:ERG urinary assay does not add significantly to standard detection and risk stratification tools.

Characterization of abiraterone responses in African American castrate-resistant prostate cancer

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Background: African American (AA) men have a higher incidence and mortality from prostate cancer (PCa) compared to other racial groups. Abiraterone acetate (Abi) is approved for treatment of mCRPC. While some AA patients were included in Abi trials, the majority of patients have been Caucasian (CA). To date, there have been no reports of Abi responses exclusively in AA men. This study evaluated Abi responses in AA men with mCRPC. Methods: PSA values during Abi treatment as well as baseline hemoglobin (Hgb), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) were tabulated. Prior therapy with docetaxel (Doc) or enzalutamide (Enza) was recorded. PSA response, progression and duration were assessed and compared between racial groups. PSA response, duration of response, and progression were defined by PCWG2 criteria. PSA half-life (PSAHL) based on time to nadir was calculated to assess rate of PSA decline. Results: A total of 74 Abi patients with mCRPC (n = 20 AA; n = 54 CA) were assessed from a single institution. Median AA baseline Hgb, ALP, LDH, and PSA were 11.8 (r = 6.4-15.4), 220 (r = 88-713), 209 (r = 157-401), and 48.41 (r = 4.8-1460) respectively. Median CA baseline Hgb, ALP, LDH, and PSA were 12.35 (r = 7.6-15), 165.5 (r = 70-1699), 218 (r = 133-528), and 44.84 (r = 1.71-2890) respectively. There were no significant differences in baseline labs between AA and CA. Prior use of Doc or Enza was 30% and 5% for AA; 31% and 4% for CA. PSA response was not significant for PSA decline of >30% (>30%: AA = 40%; CA = 44%), >50% (>50%: AA = 35%; CA = 30%), or >90% (>90%: AA = 20%; CA = 9%). In addition, no significant differences between the time to nadir (AA median = 209 days; CA median = 218 days), rate of PSA decline (AA PSAHL median = 72.4 days; CA PSAHL median = 80.1 days), or time to progression was observed. The median treatment length was 278 days and median time to progression was 66 days for AA men; 264 days and 88 days for CA men. Conclusions: Abi response rates, duration of response, and time to progression were not statistically different in AA men compared to CA men in patients with mCRPC. Larger studies are needed to fully evaluate this observation.

Clinical performance of PCA3 and TMPRSS2:ERG urinary biomarkers for African American men undergoing prostate biopsy

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Background: Urinary assaysfor PCA3 and TMPRSS2:ERG (T2:ERG) fusion are established biomarkers for the detection of prostate cancer (PCa). However few African Americans (AA) have been included in previous studies. We sought to determine the performance characteristics of these assays in a racially diverse group of men who elected to undergo prostate biopsy. Methods: Following IRB approval, from 12/2013-10/2014, post digital rectal exam urine was collected in 152 patients without a diagnosis of PCa, prior to biopsy. PCA3 and T2:ERG RNA copies were quantified using transcription-mediated amplification assays and normalized to PSA mRNA copies. Results: Of the 152 patients who met study inclusion, 93 (61%) were AA, 59 were non-AA (39%); 72(47%) were diagnosed with PCa (55% AA, 36% non-AA). Both PCA3 and T2:ERG scores were greater in men with biopsy-proven PCa, those with ≥3 PCa cores, ≥33.3% PCa cores, >50% PCa involvement of greatest biopsy core and Epstein significant PCa (all p-values ≤ 0.02). PCA3 but not T2:ERG scores were greater in men with Gleason grade ≥7 (p = 0.0003). ROC analyses for prediction of biopsy outcome resulted in AUCs of 0.7, 0.61 and 0.59 for PCA3, T2:ERG and serum PSA. For the subgroup of AA, PCA3 and T2:ERG scores were greater in men with biopsy-proven PCa, those with ≥3 PCa cores, ≥33.3% PCa cores, >50% PCa involvement of greatest biopsy core and Epstein significant PCa (all p-values ≤0.01). Both PCA3 and T2:ERG scores were greater in men with Gleason grade ≥7 (p ≤ 0.03). ROC analyses for prediction of biopsy outcome for AA only resulted in AUCs of 0.66, 0.66 and 0.58 for PCA3, T2:ERG and serum PSA. For the non-AA cohort, PCA3 scores were greater in men with biopsy-proven PCa, those with ≥3 PCa cores, ≥33.3% PCa cores, >50% PCa involvement of greatest biopsy core, Epstein significant PCa and Gleason grade ≥7 (all p-values ≤ 0.03). T2:ERG did not reach significance for any of these variables. In this subgroup, ROC analyses for prediction of biopsy outcome resulted in AUCs of 0.73, 0.54 and 0.56 for PCA3, T2:ERG and serum PSA. Conclusions: In AA men undergoing prostate biopsy, both PCA3 and T2:ERG urinary assays demonstrate clinical utility in predicting biopsy outcome and PCa disease characteristics.

Racial variation in positive prostate needle biopsy templates, which include the transition zone

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Background: Reports have suggested that African Americans (AA) with prostate cancer (PCa) have both increased incidence and increased aggressiveness of tumors located in the transition zone (TZ). Our goal was to evaluate the utility of TZ−directed prostate biopsies in a predominantly AA population at a Veterans Affairs Hospital. Methods: After obtaining IRB approval, we retrospectively reviewed all patients with PCa found on a 14 core biopsy in which 12 needle biopsies were directed at the peripheral zone (PZ) and 2 at the TZ, between January 2010 and June 2014. Location of disease was determined by the results of the biopsy, either PZ alone, TZ alone or both. Aggressiveness of disease was defined by Gleason grade, percent involvement of PCa in any core and NCCN risk-stratification. Self−identified race was recorded for all patients. A series of Mann Whitney U and Chi−square tests were used to compare variables. Results: The total patient cohort consisted of 398 men, in which 277 (70%) were AA. When compared with Caucasian Americans (CA), AA patients had more NCCN intermediate or high risk (50% vs 39%, p = 0.25) PCa. Most patients had PCa limited to the PZ only (n=190) or in both the PZ and TZ (n=191). For 17 patients (4%) PCa was limited to TZ core(s) only, 14 (5%) AA vs 3 (2%) CA (p = 0.24). Of these 17 patients, 14 (82%) had Gleason 6 only disease. Patients with PCa in both the PZ and TZ had higher PSA and PSA density, greater volume of disease, higher-grade lesions and worse NCCN category (all values p <0.01) compared with patients in which the positive biopsy was limited to the PZ. Of these 191 TZ and PZ positive patients, a greater proportion were AA (n=135, 49%) compared to CA (n=56, 46%) (p = 0.48). For patients with PZ and TZ disease, the TZ had the highest-grade in 21 (11%) men, 10% AA and 13% CA (p = 0.67). For most patients (89%), PZ tumor grade was equal to or greater than TZ. Conclusions: TZ−directed prostate needle biopsy cores were rarely the sole location of PCa and when found were usually low grade without clear racial variation. Patients with PCa in both the PZ and TZ had aggressive disease regardless of race although the TZ core resulted in upgrading in a minority of patients. TZ-directed biopsies do not appear to be of greater benefit to AA than CA.

3D Printing and Its Urologic Applications

3D printing is the development of 3D objects via an additive process in which successive layers of material are applied under computer control. This article discusses 3D printing, with an emphasis on its historical context and its potential use in the field of urology.

Active surveillance of prostate cancer in African American men

Active surveillance (AS) is a treatment strategy for prostate cancer (PCa) whereby patients diagnosed with PCa undergo ongoing characterization of their disease with the intent of avoiding radical treatment. Previously, AS has been demonstrated to be a reasonable option for men with low-risk PCa, but existing cohorts largely consist of Caucasian Americans. Because African Americans have a greater incidence, more aggressive, and potentially more lethal PCa than Caucasian Americans, it is unclear if AS is appropriate for African Americans. We performed a review of the available literature on AS with a focus on African Americans.