Impact of Gene Expression Classifier Testing on Adjuvant Treatment Following Radical Prostatectomy: The G-MINOR Prospective Randomized Cluster-crossover Trial.

BACKGROUND AND OBJECTIVE: Decipher is a tissue-based genomic classifier (GC) developed and validated in the post-radical prostatectomy (RP) setting as a predictor of metastasis. We conducted a prospective randomized controlled cluster-crossover trial assessing the use of Decipher to determine its impact on adjuvant treatment after RP. METHODS: Eligible patients had undergone RP within 9 mo of enrollment, had pT3-4 disease and/or positive surgical margins, and prostate-specific antigen <0.1 ng/ml. Centers were randomized to a sequence of 3-mo periods of either GC-informed care or usual care (UC). Cancer of the Prostate Risk Assessment Postsurgical (CAPRA-S) recurrence risk scores were provided to treating physicians and patients in all periods. KEY FINDINGS AND LIMITATIONS: Impact of GC test results on adjuvant treatment were compared with UC alone. Longitudinal patient-reported urinary and sexual function was assessed. A total of 175 patients were enrolled in 27 periods with GC and 163 in 28 periods with UC. At 18 mo after RP, an average patient in the GC arm received adjuvant treatment 9.7% of the time compared with 8.7% for an average individual in the UC arm (0.99% mean difference, 95% confidence interval [CI] -7.6%, 9.6%, p = 0.8). While controlling for CAPRA-S score, higher GC scores tended to result in an increased likelihood of adjuvant treatment that was not statistically significant (odds ratio [OR] = 1.35 per 0.1 increase in GC score, 95% CI 0.98-1.85, p = 0.066). Using the GC risk groups, reflecting clinical use, a high GC risk was associated with significantly higher odds of receiving adjuvant treatment (OR = 6.9, 95% CI 1.8, 26, p = 0.005) compared with a low GC score, adjusted for CAPRA-S score. There were no differences in patient-reported urinary and sexual function between the study arms. As oncologic outcomes are immature, the present data cannot address whether GC testing provides any cancer control benefit. CONCLUSIONS AND CLINICAL IMPLICATIONS: GC testing impacts adjuvant therapy administration when viewed through the risk categories presented in the patient report; however, these data do not provide specific support for GC testing in the adjuvant treatment setting.

Development and Optimization of a Subtraction-Normalized Immunocyte Profiling Signature for Prostate Cancer Active Surveillance Risk Stratification.

PURPOSE: Less invasive decision support tools are desperately needed to identify occult high-risk disease in men with prostate cancer (PCa) on active surveillance (AS). For a variety of reasons, many men on AS with low- or intermediate-risk disease forgo the necessary repeat surveillance biopsies needed to identify potentially higher-risk PCa. Here, we describe the development of a blood-based immunocyte transcriptomic signature to identify men harboring occult aggressive PCa. We then validate it on a biopsy-positive population with the goal of identifying men who should not be on AS and confirm those men with indolent disease who can safely remain on AS. This model uses subtraction-normalized immunocyte transcriptomic profiles to risk-stratify men with PCa who could be candidates for AS. MATERIALS AND METHODS: Men were eligible for enrollment in the study if they were determined by their physician to have a risk profile that warranted prostate biopsy. Both training (n = 1017) and validation cohort (n = 1198) populations had blood samples drawn coincident to their prostate biopsy. Purified CD2+ and CD14+ immune cells were obtained from peripheral blood mononuclear cells, and RNA was extracted and sequenced. To avoid overfitting and unnecessary complexity, a regularized regression model was built on the training cohort to predict PCa aggressiveness based on the National Comprehensive Cancer Network PCa guidelines. This model was then validated on an independent cohort of biopsy-positive men only, using National Comprehensive Cancer Network unfavorable intermediate risk and worse as an aggressiveness outcome, identifying patients who were not appropriate for AS. RESULTS: The best final model for the AS setting was obtained by combining an immunocyte transcriptomic profile based on 2 cell types with PSA density and age, reaching an AUC of 0.73 (95% CI: 0.69-0.77). The model significantly outperforms (P < .001) PSA density as a biomarker, which has an AUC of 0.69 (95% CI: 0.65-0.73). This model yields an individualized patient risk score with 90% negative predictive value and 50% positive predictive value. CONCLUSIONS: While further validation in an intended-use cohort is needed, the immunocyte transcriptomic model offers a promising tool for risk stratification of individual patients who are being considered for AS.

Positive Impact of Implementing a Comprehensive Genetic Testing Protocol for Prostate Cancer Patients in a Multi-disciplinary Uro-oncology Practice.

INTRODUCTION: Prior to the 2017 Philadelphia Consensus Conference guidelines, genetic testing for prostate cancer was conducted based on personal and family history of malignancy pursuant to National Comprehensive Cancer Network recommendations. The updated 2019 guidelines addressed the subject of genetic testing by endorsing point-of-care genetic testing and referral to genetic counseling. However, limited literature is available regarding successful implementation of a streamlined method for genetic testing. This paper explores the benefits of implementing an on-site guideline-based genetic testing process for prostate cancer patients. METHODS: Data were retrospectively reviewed for 552 prostate cancer patients seen in a uro-oncology clinic since January 2017. Prior to September 2018 genetic testing was recommended based on National Comprehensive Cancer Network guidelines, and swabs for testing were procured off-site 1 mile from the clinic (n = 78). After September 2018 genetic testing was recommended based on the Philadelphia Consensus Conference guidelines, and swabs for testing were procured at the clinic itself (n = 474). RESULTS: A statistically significant increase in testing compliance was observed after the implementation of on-site, guideline-based testing. Genetic testing compliance increased from 33.3% to 98.7%. The time to receive the genetic test results was also reduced from 38 days to 21 days. CONCLUSIONS: The implementation of an on-site, guideline-based genetic testing model for prostate cancer patients significantly improved compliance with genetic testing to 98.7% and decreased the time to receive genetic test results by 17 days. Adopting a guideline-based model with on-site genetic testing can significantly improve the detection rate for pathogenic and actionable mutations and increase the utilization of targeted therapies.

Evaluation of an RNAseq-Based Immunogenomic Liquid Biopsy Approach in Early-Stage Prostate Cancer.

The primary objective of this study is to detect biomarkers and develop models that enable the identification of clinically significant prostate cancer and to understand the biologic implications of the genes involved. Peripheral blood samples (1018 patients) were split chronologically into independent training (n = 713) and validation (n = 305) sets. Whole transcriptome RNA sequencing was performed on isolated phagocytic CD14+ and non-phagocytic CD2+ cells and their gene expression levels were used to develop predictive models that correlate to adverse pathologic features. The immune-transcriptomic model with the highest performance for predicting adverse pathology, based on a subtraction of the log-transformed expression signals of the two cell types, displayed an area under the curve (AUC) of the receiver operating characteristic of 0.70. The addition of biomarkers in combination with traditional clinical risk factors (age, serum prostate-specific antigen (PSA), PSA density, race, digital rectal examination (DRE), and family history) enhanced the AUC to 0.91 and 0.83 for the training and validation sets, respectively. The markers identified by this approach uncovered specific pathway associations relevant to (prostate) cancer biology. Increased phagocytic activity in conjunction with cancer-associated (mis-)regulation is also represented by these markers. Differential gene expression of circulating immune cells gives insight into the cellular immune response to early tumor development and immune surveillance.

Clinical outcomes in men with prostate cancer who selected active surveillance using a clinical cell cycle risk score.

Aim: To evaluate active surveillance (AS) selection, safety and durability among men with low-risk prostate cancer assessed using the clinical cell cycle risk (CCR) score, a combined clinical and molecular score. Patients & methods: Initial treatment selection (AS vs treatment) and duration of AS were evaluated for men with low-risk prostate cancer according to the CCR score and National Comprehensive Cancer Network guidelines. Adverse events included biochemical recurrence and metastasis. Results: 82.4% (547/664) of men initially selected AS (median follow-up: 2.2 years), 0.4% (2/547) of whom experienced an adverse event. Two-thirds of patients remained on AS for more than 3 years; patient choice was the most common reason for leaving AS. Conclusion: The CCR score may aid in the identification of men who can safely defer prostate cancer treatment.

Urinary Molecular Biomarker Test Impacts Prostate Biopsy Decision Making in Clinical Practice.

INTRODUCTION: There is an unmet need for noninvasive methods to better identify patients at increased risk for clinically significant prostate cancer. SelectMDx® is a molecular urine test validated for the detection of Gleason score 7 and higher cancers (ISUP [International Society of Urological Pathology] Grade Group 2-5). In this multicenter trial we evaluated the test's impact on prostate biopsy decision making in clinical practice. METHODS: The study involved 5 U.S. community urology practices which sequentially enrolled 418 patients who received a SelectMDx test between May 2016 and April 2017 while undergoing evaluation for initial prostate biopsy. All tests were ordered by the urologist for patient management. We determined biopsy and prostate cancer detection rates in patients with SelectMDx positive versus SelectMDx negative results. RESULTS: Of the 418 subjects evaluated with SelectMDx 253 (61%) had negative results and 165 (39%) had positive results. Subsequent biopsy rates for SelectMDx positive and negative cases were 60% (99) and 12% (32), respectively (p <0.001). Time from SelectMDx result to biopsy was shorter for those with positive vs negative results (median 2 vs 5 months, p=0.001). Of patients who underwent biopsy within 3 months of testing 71 (43%) with positive results underwent biopsy and 27 had cancers identified, including 10 greater than Grade Group 2. Of 9 patients with SelectMDx negative results (3.6%) who underwent biopsy 4 were diagnosed with cancer, all Grade Group 2 or less. CONCLUSIONS: SelectMDx had a significant impact on initial prostate biopsy decision making. Biopsy rates in SelectMDx positive cases were fivefold higher than in SelectMDx negative cases. These results describe the clinical utility of SelectMDx in real-world community urology practice.

Specimen Provenance Testing Identifies Contamination That Affects Molecular Prognostic Assay Results in Prostate Cancer Biopsy Specimens.

OBJECTIVE: To determine if tissue contamination in histologic specimens can significantly affect the results of prognostic molecular markers that are routinely used as confirmatory tests to safely assign appropriate candidates to prostate cancer active surveillance protocols. MATERIALS AND METHODS: This study evaluates 2134 cases from a single, large urology practice that were successfully tested for DNA specimen provenance verification using short tandem repeat analysis for the presence of a significant level of contaminating DNA. After removal of the contamination, 5 of the samples were retested, and the results of the molecular diagnostic test were compared. RESULTS: Forty-nine of the 2134 cases (2.3%) sent for DNA provenance analysis were found to possess significant levels of contamination. Of these 49 cases, 7 were resent for a repeat molecular diagnostic test after being decontaminated. Five of these prostate cancer specimens had sufficient tissue and RNA to give a more accurate cell cycle progression (CCP) score. The average absolute change in these patients' CCP scores was 0.48, with a minimum of 0.1-unit and a maximum of 1.0-unit difference. These changes in CCP scores are significant enough to cause meaningful alterations in a patient's calculated 10-year mortality rate, as defined by their combined risk score. CONCLUSION: DNA contamination in unstained tissue sections sent for prognostic prostate cancer molecular diagnostic testing occurs in 2.3% of the cases, and can be of a magnitude that affects the results and subsequent clinical decision of appropriateness for active surveillance.

Prostatectomy-based validation of combined urine and plasma test for predicting high grade prostate cancer.

BACKGROUND: Distinguishing between low- and high-grade prostate cancers (PCa) is important, but biopsy may underestimate the actual grade of cancer. We have previously shown that urine/plasma-based prostate-specific biomarkers can predict high grade PCa. Our objective was to determine the accuracy of a test using cell-free RNA levels of biomarkers in predicting prostatectomy results. METHODS: This multicenter community-based prospective study was conducted using urine/blood samples collected from 306 patients. All recruited patients were treatment-naïve, without metastases, and had been biopsied, designated a Gleason Score (GS) based on biopsy, and assigned to prostatectomy prior to participation in the study. The primary outcome measure was the urine/plasma test accuracy in predicting high grade PCa on prostatectomy compared with biopsy findings. Sensitivity and specificity were calculated using standard formulas, while comparisons between groups were performed using the Wilcoxon Rank Sum, Kruskal-Wallis, Chi-Square, and Fisher's exact test. RESULTS: GS as assigned by standard 10-12 core biopsies was 3 + 3 in 90 (29.4%), 3 + 4 in 122 (39.8%), 4 + 3 in 50 (16.3%), and > 4 + 3 in 44 (14.4%) patients. The urine/plasma assay confirmed a previous validation and was highly accurate in predicting the presence of high-grade PCa (Gleason ≥3 + 4) with sensitivity between 88% and 95% as verified by prostatectomy findings. GS was upgraded after prostatectomy in 27% of patients and downgraded in 12% of patients. CONCLUSIONS: This plasma/urine biomarker test accurately predicts high grade cancer as determined by prostatectomy with a sensitivity at 92-97%, while the sensitivity of core biopsies was 78%.

Clinical Utility of Gene Expression Classifiers in Men With Newly Diagnosed Prostate Cancer.

PURPOSE: Tissue-based gene expression classifiers (GECs) may assist with management decisions in patients with newly diagnosed prostate cancer. We sought to assess the current use of GEC tests and determine how the test results are associated with primary disease management. METHODS: In this observational study, patients diagnosed with localized prostate cancer were tracked through the Michigan Urological Surgery Improvement Collaborative registry. The utilization and results of three GECs (Decipher Prostate Biopsy, Oncotype DX Prostate, and Prolaris) were prospectively collected. Practice patterns, predictors of GEC use, and effect of GEC results on disease management were investigated. RESULTS: Of 3,966 newly diagnosed patients, 747 (18.8%) underwent GEC testing. The rate of GEC use in individual practices ranged from 0% to 93%, and patients undergoing GEC testing were more likely to have a lower prostate-specific antigen level, lower Gleason score, lower clinical T stage, and fewer positive cores (all P < .05). Among patients with clinical favorable risk of cancer, the rate of active surveillance (AS) differed significantly among patients with a GEC result above the threshold (46.2%), those with a GEC result below the threshold (75.9%), and those who did not undergo GEC (57.9%; P < .001 for comparison of the three groups). This results in an estimate that, for every nine men with favorable risk of cancer who undergo GEC testing, one additional patient may have their disease initially managed with AS. On multivariable analysis, patients with favorable-risk prostate cancer who were classified as GEC low risk were more likely to be managed on AS than those without testing (odds ratio, 1.84; P = .006). CONCLUSION: There is large variability in practice-level use and GEC tests ordered in patients with newly diagnosed, localized prostate cancer. In patients with clinical favorable risk of cancer, GEC testing significantly increased the use of AS. Additional follow-up will help determine whether incorporation of GEC testing into initial patient care favorably affects clinical outcomes.

A Multi-Center Prospective Study to Validate an Algorithm Using Urine and Plasma Biomarkers for Predicting Gleason ≥3+4 Prostate Cancer on Biopsy.

Background: Unnecessary biopsies and overdiagnosis of prostate cancer (PCa) remain a serious healthcare problem. We have previously shown that urine- and plasma-based prostate-specific biomarkers when combined can predict high grade prostate cancer (PCa). To further validate this test, we performed a prospective multicenter study recruiting patients from community-based practices. Patients and Methods: Urine and plasma samples from 2528 men were tested prospectively. Results were correlated with biopsy findings, if a biopsy was performed as deemed necessary by the practicing urologist. Of the 2528 patients, biopsy was performed on only 524 (21%) patients. Results: Of the 524 patients, Gleason≥3+4 PCa was found in 161 (31%) and Gleason ≥4+3 was found in 62 (12%) of the patients. The urine/plasma biomarkers algorithm showed sensitivity and specificity of 75% and 69% for predicting Gleason ≥3+4. However, upon incorporating prostate size and prior history of biopsy in the algorithm, we achieved a sensitivity between 97% and 86% and a specificity between 36% and 57%, dependent on the used cut-off point. Sensitivity for predicting PCa Gleason ≥4+3 was between 96% and 99% and specificity between 59% and 37%, dependent on the cut-off point. Diagnosis of Gleason ≥3+4 was missed in 1% to 3% of tested patients and of Gleason ≥4+3 in 0.2% to 1%. Conclusion: This test when integrated with prostate volume and the prior prostate biopsy enhance the sensitivity and specificity for predicting the presence of high grade prostate cancer with negative predictive value (NPV) of 90% to 97% for Gleason ≥3+4 and between 98% to 99% for Gleason ≥4+3.

The clinical and economic implications of specimen provenance complications in diagnostic prostate biopsies.

PURPOSE: Inaccurate diagnoses of prostate cancer can result from transposition or contamination of patient biopsy specimens, which are known as specimen provenance complications. We assessed the clinical and economic burden of specimen provenance complications in prostate biopsies in the United States. MATERIALS AND METHODS: We performed a comprehensive, systematic review of the literature to approximate the effect of specimen provenance complications on direct medical costs, patient QALYs and medicolegal costs. Data were extracted from published studies on specimen provenance complications rates, prostate cancer treatment efficacy, treatment cost, litigation/settlement costs after false diagnoses of prostate biopsies and patient quality of life. Sensitivity analysis was done to identify factors that most influenced the outcomes and assess the robustness of the findings. RESULTS: Of the estimated 806,251 primary and secondary prostate biopsies performed annually in the United States 20,322 specimen provenance complications were projected to result in 4,570 clinically meaningful false diagnoses and an expected loss of 634 QALYs. The total burden of specimen provenance complications was projected to exceed $879.9 million or $3,776 per positive cancer diagnosis. This estimate was most sensitive to the indemnity cost per false-positive case and the rate of transpositions at independent reference laboratories. CONCLUSIONS: The societal burden of specimen provenance complications in patients who undergo prostate biopsy exceeds $880 million annually in the United States. This analysis framework may be useful as policy makers, health organizations and researchers seek to decrease false diagnoses of prostate cancer and the consequent effects of delayed or unnecessary treatment. Further study is warranted to quantify the economic burden among additional diseases.

Reduced Rate of Repeated Prostate Biopsies Observed in ConfirmMDx Clinical Utility Field Study.

BACKGROUND: The diagnosis of prostate cancer is dependent on histologic confirmation in biopsy core tissues. The biopsy procedure is invasive, puts the patient at risk for complications, and is subject to significant sampling errors. An epigenetic test that uses methylation-specific polymerase chain reaction to determine the epigenetic status of the prostate cancer-associated genes GSTP1, APC, and RASSF1 has been clinically validated and is used in clinical practice to increase the negative predictive value in men with no history of prostate cancer compared with standard histopathology. Such information can help to avoid unnecessary repeat biopsies. The repeat biopsy rate may provide preliminary clinical utility evidence in relation to this assay's potential impact on the number of unnecessary repeat prostate biopsies performed in US urology practices. OBJECTIVE: The purpose of this preliminary study was to quantify the number of repeat prostate biopsy procedures to demonstrate a low repeat biopsy rate for men with a history of negative histopathology who received a negative epigenetic assay result on testing of the residual prostate tissue. METHODS: In this recently completed field observation study, practicing urologists used the epigenetic test called ConfirmMDx for Prostate Cancer (MDxHealth, Inc, Irvine, CA) to evaluate cancer-negative men considered at risk for prostate cancer. This test has been previously validated in 2 blinded multicenter studies that showed the superior negative predictive value of the epigenetic test over standard histopathology for cancer detection in prostate biopsies. A total of 5 clinical urology practices that had ordered a minimum of 40 commercial epigenetic test requisitions for patients with previous, cancer-negative biopsies over the course of the previous 18 months were contacted to assess their interest to participate in the study. Select demographic and prostate-screening parameter information, as well as the incidence of repeat biopsy, specifically for patients with a negative test result, was collected and merged into 1 collective database. All men from each of the 5 sites who had negative assay results were included in the analysis. RESULTS: A total of 138 patients were identified in these urology practices and were included in the analysis. The median age of the men was 63 years, and the current median serum prostate-specific antigen level was 4.7 ng/mL. Repeat biopsies had been performed in 6 of the 138 (4.3%) men with a negative epigenetic assay result, in whom no evidence of cancer was found on histopathology. CONCLUSION: In this study, a low rate of repeat prostatic biopsies was observed in the group of men with previous histopathologically negative biopsies who were considered to be at risk for harboring cancer. The data suggest that patients managed using the ConfirmMDx for Prostate Cancer negative results had a low rate of repeat prostate biopsies. These results warrant a large, controlled, prospective study to further evaluate the clinical utility of the epigenetic test to lower the unnecessary repeat biopsy rate.

The E2F1/DNMT1 axis is associated with the development of AR negative castration resistant prostate cancer.

BACKGROUND: Research on castration resistant prostate cancer (CRPC) has focused primarily on functional alterations of the androgen receptor (AR). However, little is known about the loss of AR gene expression itself and the possible contribution of AR negative cells to CRPC. METHODS: Human and murine prostate cancer tissue microarrays (TMAs) were evaluated with antibodies specific for E2F1, DNA methyltransferase 1 or AR. The human prostate cancer TMA consisted of clinical samples ranging from normal tissue to samples of metastatic disease. The murine TMA was comprised of benign, localized or metastatic prostate cancer acquired from TRAMP mice treated with castration and/or 5'-Aza-2'-deoxycytidine (5Aza). RESULTS: Immunohistochemical analysis revealed increased nuclear DNMT1 staining in localized PCa (P < 0.0001) and metastatic PCa (P < 0.0001) compared to normal tissue. Examination of specific diagnoses revealed that Gleason seven tumors exhibited greater nuclear DNMT1 staining than Gleason six tumors (P < 0.05) and that metastatic tissue exhibited greater levels of nuclear DNMT1 than Gleason seven tumors (P < 0.01). Evaluation of the murine tissue cores revealed that 8.2% and 8.1% of benign tissue cores stained positive for E2F1 and DNMT1 respectively, while 97.0% were AR positive. Conversely, 81% and 100% of tumors were positive for E2F1 and DNMT1 respectively. This was in stark contrast to only 18% of tumors positive for AR. Treatment of mice with 5Aza reduced DNMT1 staining by 30%, while AR increased by 27%. CONCLUSIONS: These findings demonstrate that the E2F1/DNMT1 inhibitory axis of AR transcription is activated during the emergence of CRPC.

Repression of androgen receptor transcription through the E2F1/DNMT1 axis.

Although androgen receptor (AR) function has been extensively studied, regulation of the AR gene itself has been much less characterized. In this study, we observed a dramatic reduction in the expression of androgen receptor mRNA and protein in hyperproliferative prostate epithelium of keratin 5 promoter driven E2F1 transgenic mice. To confirm an inhibitory function for E2F1 on AR transcription, we showed that E2F1 inhibited the transcription of endogenous AR mRNA, subsequent AR protein, and AR promoter activity in both human and mouse epithelial cells. E2F1 also inhibited androgen-stimulated activation of two AR target gene promoters. To elucidate the molecular mechanism of E2F-mediated inhibition of AR, we evaluated the effects of two functional E2F1 mutants on AR promoter activity and found that the transactivation domain appears to mediate E2F1 repression of the AR promoter. Because DNMT1 is a functional intermediate of E2F1 we examined DNMT1 function in AR repression. Repression of endogenous AR in normal human prostate epithelial cells was relieved by DNMT1 shRNA knock down. DNMT1 was shown to be physically associated within the AR minimal promoter located 22 bps from the transcription start site; however, methylation remained unchanged at the promoter regardless of DNMT1 expression. Taken together, our results suggest that DNMT1 operates either as a functional intermediary or in cooperation with E2F1 inhibiting AR gene expression in a methylation independent manner.

Molecular markers that can be utilized in diet and dietary supplement research.

Prostate and other cancers have a multitude of potential markers that can be used in laboratory and clinical studies of diet and dietary supplement interventions. More overt clinical markers include imaging tests, biopsy samples, prostate-specific antigen kinetics, and urinary testing. Many molecular markers are currently available, including antiapoptotic and apoptotic proteins, cell adhesion molecules, cell cycle compounds, growth factors, angiogenic markers, and proliferative and inflammatory signals. Protein kinases and transcription factors should also be considered for diversity. Testing of numerous molecular markers has become critical in gaining preliminary insight into the potential impact of a novel diet and supplemental agents.

Is residual neurovascular tissue on prostatectomy specimens associated with surgeon intent at nerve-sparing and postoperative quality of life measures?

OBJECTIVES: Preservation of periprostatic neurovascular tissue at the time of radical prostatectomy has been correlated with subsequent erectile function and urinary continence. We evaluated whether the amount of neurovascular tissue identified on prostatectomy specimens correlated with surgeon's intention of nerve-sparing and/or predicted quality of life outcomes. MATERIALS AND METHODS: Radical prostatectomy specimens from 60 patients were evaluated by 2 pathologists for residual neurovascular bundle tissue. Reviewable pathology was available for 17, 19, and 19 patients with bilateral, unilateral, and non-nerve-sparing radical prostatectomy, respectively. The patients completed the Expanded Prostate Cancer Index Composite, a validated quality of life questionnaire. Differences between neurovascular tissue thickness, surgeon's intent at nerve-sparing, and quality of life among patients in each group were analyzed using standard statistical software. RESULTS: Neurovascular tissue thickness identified on radical prostatectomy specimens did not correlate with surgeon's intent at performing a nerve-sparing procedure, nor was it found to be predictive of postoperative quality of life. Surgeon's intent at neurovascular preservation, however, was associated with improved sexual and urinary function scores at 1 year (both P < 0.05). CONCLUSIONS: Surgeon intent, regardless of the amount of neurovascular tissue identified on radical prostatectomy specimen, is predictive of postoperative sexual-related and urinary quality of life. This suggests that factors other than the amount of neurovascular tissue spared contribute to postoperative sexual and urinary function.

Histotripsy of the prostate: dose effects in a chronic canine model.

OBJECTIVES: To develop the technique of histotripsy ultrasound therapy as a noninvasive treatment for benign prostatic hyperplasia and to examine the histotripsy dose-tissue response effect over time to provide an insight for treatment optimization. We have previously demonstrated the feasibility of prostate histotripsy fractionation in a canine model. METHODS: Various doses of histotripsy were applied transabdominally to the prostates of 20 canine subjects. Treated prostates were then harvested at interval time points from 0 to 28 days and assessed for histologic treatment response. RESULTS: The lowest dose applied was found to produce only scattered cellular disruption and necrosis, whereas higher doses produced more significant regions of tissue effect that resulted in sufficient fractionation of tissue so the material could be voided with urination. Urethral tissue was more resistant to the lower histotripsy doses than was parenchymal tissue. Treatment of the urethra at the lowest doses appeared to heal, with minimal long-term sequelae. CONCLUSIONS: Histotripsy was effective at fractionating parenchymal and urethral tissue in the prostate, in the presence of a sufficient dose. Further development of this technique could lead to a noninvasive method for debulking the prostate to relieve symptoms associated with benign prostatic hyperplasia.

Rational approach to implementation of prostate cancer antigen 3 into clinical care.

BACKGROUND: Prostate cancer antigen 3 (PCA3) encodes a prostate-specific messenger ribonucleic acid (mRNA) that serves as the target for a novel urinary molecular assay for prostate cancer detection. The objective of the current study was to evaluate the ability of PCA3, added to measurements of serum prostate-specific antigen (PSA), to predict cancer detection by extended template biopsy. METHODS: Between September 2006 and December 2007, whole urine samples were collected after attentive digital rectal examinations from 187 men before they underwent ultrasound-guided, 12-core prostate biopsy in a urology outpatient clinic. Urine PCA3/PSA mRNA ratio scores were measured within 1 month, and serum PSA was measured within 6 months prior to biopsy. Those measurements were related to cancer-positive biopsies. RESULTS: Overall, 87 of 187 biopsies (46.5%) were positive for cancer. The sensitivity and specificity of a PCA3 score > or =35 for positive biopsy were 52.9% and 80%, respectively, and the positive and negative predictive values were 69.7% and 66.1%, respectively. By using receiver operating characteristic curve analysis, PSA alone resulted in an area under the curve (AUC) of 0.63 for prostate cancer detection; whereas a combined PSA and PCA3 score resulted in an AUC of 0.71. The likelihood of prostate cancer detection rose with increasing PCA3 score ranges (P > .0001), providing possible PCA3 score parameters for stratification into groups at low risk, moderate risk, high risk, and very high risk for a positive biopsy. CONCLUSIONS: Adding PCA3 to serum PSA improved prostate cancer prediction. The use of PCA3 in a clinical setting may help to stratify patients according to their risk for biopsy and cancer detection, although a large-scale validation study will be needed to address assay standardization, optimal cutoff values, and appropriate patient populations.

Body composition and serum prostate-specific antigen: review and findings from Flint Men's Health Study.

Recent studies have suggested that obesity is associated with lower serum prostate-specific antigen levels, perhaps influencing the recommendation for prostate biopsy and potentially explaining part of the observed poorer prognosis among obese men. African-American men have the greatest rates of prostate cancer and are more likely to die of the disease, making early detection a priority in this group. We present findings from the Flint Men's Health Study, a study of African-American men, that are consistent with most studies suggesting that overweight men have prostate-specific antigen levels that are 0.15 to 0.30 ng/mL lower than those who are not overweight. We have coupled our results with a systematic review of publications in this area.

Glutamine tract length of human androgen receptors affects hormone-dependent and -independent prostate cancer in mice.

The androgen receptor (AR) is involved in the initiation and progression of prostate cancer and its transition to androgen independence. Genetic variation in AR may contribute to disease risk and has been studied for a polymorphic N-terminal glutamine (Q) tract that shows population heterogeneity. While the length of this tract is known to affect AR in vitro, association with disease is complicated by genetic and environmental factors that have led to discordant epidemiological findings. To clarify the effect of Q tract polymorphism on prostate cancer, we created mice bearing humanized AR genes (h/mAr) varying in Q tract length. ARs with short Q tracts (12Q), which are transcriptionally more active, induce earlier disease in the transgene-induced TRAMP prostate cancer model than alleles with median (21Q) or long (48Q) tracts. Disease length varies within each genotype, with greater differentiation and AR expression in slower growing tumors. Remarkably, following androgen ablation, Q tract length has effects that are also allele-dependent and in directions opposite to those in hormone intact mice. Differences in AR activity conferred by Q tract length thus appear to direct distinct pathways of androgen-independent as well as androgen-dependent progression, and highlight substantial risk that may be associated with alterations in the androgen axis. This AR allelic series in humanized mice provides an experimental paradigm to dissect the role of AR in prostate cancer initiation and progression, to model response to treatment and to test therapies targeted specifically to the human AR.