Long-Term Outcomes in Patients Using Protocol-Directed Active Surveillance for Prostate Cancer.

Importance: Outcomes from protocol-directed active surveillance for favorable-risk prostate cancers are needed to support decision-making. Objective: To characterize the long-term oncological outcomes of patients receiving active surveillance in a multicenter, protocol-directed cohort. Design, Setting, and Participants: The Canary Prostate Active Surveillance Study (PASS) is a prospective cohort study initiated in 2008. A cohort of 2155 men with favorable-risk prostate cancer and no prior treatment were enrolled at 10 North American centers through August 2022. Exposure: Active surveillance for prostate cancer. Main Outcomes and Measures: Cumulative incidence of biopsy grade reclassification, treatment, metastasis, prostate cancer mortality, overall mortality, and recurrence after treatment in patients treated after the first or subsequent surveillance biopsies. Results: Among 2155 patients with localized prostate cancer, the median follow-up was 7.2 years, median age was 63 years, 83% were White, 7% were Black, 90% were diagnosed with grade group 1 cancer, and median prostate-specific antigen (PSA) was 5.2 ng/mL. Ten years after diagnosis, the incidence of biopsy grade reclassification and treatment were 43% (95% CI, 40%-45%) and 49% (95% CI, 47%-52%), respectively. There were 425 and 396 patients treated after confirmatory or subsequent surveillance biopsies (median of 1.5 and 4.6 years after diagnosis, respectively) and the 5-year rates of recurrence were 11% (95% CI, 7%-15%) and 8% (95% CI, 5%-11%), respectively. Progression to metastatic cancer occurred in 21 participants and there were 3 prostate cancer-related deaths. The estimated rates of metastasis or prostate cancer-specific mortality at 10 years after diagnosis were 1.4% (95% CI, 0.7%-2%) and 0.1% (95% CI, 0%-0.4%), respectively; overall mortality in the same time period was 5.1% (95% CI, 3.8%-6.4%). Conclusions and Relevance: In this study, 10 years after diagnosis, 49% of men remained free of progression or treatment, less than 2% developed metastatic disease, and less than 1% died of their disease. Later progression and treatment during surveillance were not associated with worse outcomes. These results demonstrate active surveillance as an effective management strategy for patients diagnosed with favorable-risk prostate cancer.

Prevalence of genotoxic bacteria in men undergoing biopsy for prostate cancer.

BACKGROUND: New evidence suggests that bacteria-produced DNA toxins may have a role in the development or progression of prostate cancer. To determine the prevalence of these genes in a noninfection (i.e., colonized) state, we screened urine specimens in men before undergoing a biopsy for prostate cancer detection. METHODS: We developed a multiplex polymerase chain reaction using three of the most described bacterial genotoxin gene primers: Colibactin (polyketone synthase [pks] gene island: clbN and clbB), cytotoxic necrotizing factor (cnf1) toxin, and cytolethal distending toxin B (cdtB) represented gene islands. After calibration on Escherichia coli samples of known genotypes, we used a training and validation cohort. We performed multiplex testing on a training cohort of previously collected urine from 45 men undergoing prostate biopsy. For the validation cohort, we utilized baseline urine samples from a previous randomized clinical trial (n = 263) with known prostate cancer outcomes. RESULTS: The prevalence of four common bacterial genotoxin genes detected in the urine before prostate biopsy for prostate cancer is 8% (25/311). The prevalence of pks island (clbN and clbB), cnf1, and cdt toxin genes are 6.1%, 2.4%, and 1.7%, respectively. We found no association between urinary genotoxins and prostate cancer (p = 0.83). We did identify a higher proportion of low-grade cancer (92% vs. 44%) in those men positive for urinary genotoxin and higher-grade cancer in those genotoxin negative (8% vs. 56%, p = 0.001). CONCLUSIONS: The prevalence of urinary genotoxins is low and does not correspond to a prostate cancer diagnosis. The urine was taken at one point in time and does not rule out the possibility of previous exposure.

Diabetes, Obesity, and Pathological Upstaging in Renal Cell Carcinoma: Results From a Large Multi-institutional Consortium.

PURPOSE: We sought to determine whether clinical risk factors and morphometric features on preoperative imaging can be utilized to identify those patients with cT1 tumors who are at higher risk of upstaging (pT3a). MATERIALS AND METHODS: We performed a retrospective international case-control study of consecutive patients treated surgically with radical or partial nephrectomy for nonmetastatic renal cell carcinoma (cT1 N0) conducted between January 2010 and December 2018. Multivariable logistic regression models were used to study associations of preoperative risk factors on pT3a pathological upstaging among all patients, as well as subsets with those with preoperative tumors ≤4 cm, renal nephrometry scores, tumors ≤4 cm with nephrometry scores, and clear cell histology. We also examined association with pT3a subsets (renal vein, sinus fat, perinephric fat). RESULTS: Among the 4,092 partial nephrectomy and 2,056 radical nephrectomy patients, pathological upstaging occurred in 4.9% and 23.3%, respectively. Among each group independent factors associated with pT3a upstaging were increasing preoperative tumor size, increasing age, and the presence of diabetes. Specifically, among partial nephrectomy subjects diabetes (OR=1.65; 95% CI 1.17, 2.29), male sex (OR=1.62; 95% CI 1.14, 2.33), and increasing BMI (OR=1.03; 95% CI 1.00, 1.05 per 1 unit BMI) were statistically associated with upstaging. Subset analyses identified hilar tumors as more likely to be upstaged (partial nephrectomy OR=1.91; 95% CI 1.12, 3.16; radical nephrectomy OR=2.16; 95% CI 1.44, 3.25). CONCLUSIONS: Diabetes and higher BMI were associated with pathological upstaging, as were preoperative tumor size, increased age, and male sex. Similarly, hilar tumors were frequently upstaged.

Absolute Prostate Specific Antigen after 6 Months of Androgen Deprivation Therapy Is a Predictor of Overall and Cancer-Specific Mortality in Men with Hormone-Sensitive Prostate Cancer.

PURPOSE: We sought to determine if absolute prostate specific antigen (PSA) value after 6 months of androgen deprivation therapy (ADT) is predictive of subsequent survival in patients with prostate adenocarcinoma. MATERIALS AND METHODS: We performed a retrospective review of men receiving care within the Veterans Health Administration who initiated ADT for prostate adenocarcinoma. We used low- (≤0.2 ng/ml), intermediate- (>0.2 to 4 ng/ml) and high-risk (>4 ng/ml) absolute PSA values after 6-9 months of ADT, previously described in Southwest Oncology Group trial 9346. The primary endpoints were all-cause mortality and prostate cancer-specific mortality (PCSM). Kaplan-Meier survival curves for each PSA category were estimated and log-rank test was conducted. We employed Cox regression analysis adjusted for covariates and inverse propensity score weights associated with PSA categories to estimate the PSA category association with PCSM and all-cause mortality. RESULTS: We identified 9,170 patients in our cohort. Following ADT induction, 3,508 patients had low, 3,419 had intermediate and 2,243 had high PSA values. Two- and 5-year survival rates for low, intermediate and high PSA groups were 93.9% and 85.2% vs 88.6% and 71.2% vs 63.6% and 38.6%, respectively (p <0.0001). Patients in the high and intermediate PSA categories had a 15-fold and 3-fold higher risk of PCSM compared to those with PSA <0.2 ng/ml (p <0.0001). CONCLUSIONS: Absolute PSA in hormone-sensitive prostate cancer after 6-9 months of ADT is a predictor of overall mortality and PCSM. This measure can rapidly assess the efficacy of new interventions in phase 2 clinical trials.

A Decade of Robotic-Assisted Radical Nephrectomy with Inferior Vena Cava Thrombectomy: A Systematic Review and Meta-Analysis of Perioperative Outcomes.

PURPOSE: Open radical nephrectomy with inferior vena cava thrombectomy (O-CT) is standard management for renal cell carcinoma with inferior vena cava thrombus. First reported a decade ago, robotic-assisted radical nephrectomy with inferior vena cava thrombectomy (R-CT) is a minimally invasive option for this disease. We aimed to perform a systematic review to assess the safety and feasibility of R-CT in terms of perioperative outcomes and compare the outcomes between R-CT and O-CT. MATERIALS AND METHODS: The PubMed®, Scopus®, Cochrane Central Register of Controlled Trials and Web of ScienceTM databases were searched using the free-text and MeSH terms "renal cell carcinoma," "inferior vena cava," "thrombosis" or "thrombus," "robot" and "thrombectomy." Studies reporting perioperative outcomes of R-CT and studies comparing R-CT with O-CT were included. The review was done in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. RESULTS: The search retrieved 28 articles describing R-CT, including 7 comparative studies. This systematic review included 1,375 patients, out of which 329 patients were in single-arm studies and 1,046 patients were in comparative studies. Of the 329 patients who underwent R-CT, 14.7% were level I, 60.9% level II, 20.4% level III and 2.5% level IV thrombus. Operative time ranged from 150 to 530 minutes; blood transfusion was administered in 38.2% (126). The overall complication rate was 30.3% (99). R-CT, in comparison to O-CT, was associated with a lower blood transfusion rate (18.4% vs 64.3%, p=0.002) and a lower complication rate (14.5% vs 36.7%, p=0.005). Major complication and 30-day mortality rates were similar in both groups. CONCLUSIONS: R-CT has acceptable perioperative outcomes in carefully selected patients. Compared with O-CT, R-CT is associated with a lower blood transfusion rate and fewer overall complications. In experienced hands with carefully selected patients, R-CT is feasible and safe, with acceptable outcomes; however, selection bias limits definitive inference of these results, and optimal patient selection criteria remain to be described.

Impact of Prostate Health Index Results for Prediction of Biopsy Grade Reclassification During Active Surveillance.

PURPOSE: We assessed whether Prostate Health Index results improve prediction of grade reclassification for men on active surveillance. METHODS AND MATERIALS: We identified men in Canary Prostate Active Surveillance Study with Grade Group 1 cancer. Outcome was grade reclassification to Grade Group 2+ cancer. We considered decision rules to maximize specificity with sensitivity set at 95%. We derived rules based on clinical data (R1) vs clinical data+Prostate Health Index (R3). We considered an "or"-logic rule combining clinical score and Prostate Health Index (R4), and a "2-step" rule using clinical data followed by risk stratification based on Prostate Health Index (R2). Rules were applied to a validation set, where values of R2-R4 vs R1 for specificity and sensitivity were evaluated. RESULTS: We included 1,532 biopsies (n = 610 discovery; n = 922 validation) among 1,142 men. Grade reclassification was seen in 27% of biopsies (23% discovery, 29% validation). Among the discovery set, at 95% sensitivity, R2 yielded highest specificity at 27% vs 17% for R1. In the validation set, R3 had best performance vs R1 with Δsensitivity = -4% and Δspecificity = +6%. There was slight improvement for R3 vs R1 for confirmatory biopsy (AUC 0.745 vs R1 0.724, ΔAUC 0.021, 95% CI 0.002-0.041) but not for subsequent biopsies (ΔAUC -0.012, 95% CI -0.031-0.006). R3 did not have better discrimination vs R1 among the biopsy cohort overall (ΔAUC 0.007, 95% CI -0.007-0.020). CONCLUSIONS: Among active surveillance patients, using Prostate Health Index with clinical data modestly improved prediction of grade reclassification on confirmatory biopsy and did not improve prediction on subsequent biopsies.

Accommodating heterogeneous missing data patterns for prostate cancer risk prediction.

BACKGROUND: We compared six commonly used logistic regression methods for accommodating missing risk factor data from multiple heterogeneous cohorts, in which some cohorts do not collect some risk factors at all, and developed an online risk prediction tool that accommodates missing risk factors from the end-user. METHODS: Ten North American and European cohorts from the Prostate Biopsy Collaborative Group (PBCG) were used for fitting a risk prediction tool for clinically significant prostate cancer, defined as Gleason grade group ≥ 2 on standard TRUS prostate biopsy. One large European PBCG cohort was withheld for external validation, where calibration-in-the-large (CIL), calibration curves, and area-underneath-the-receiver-operating characteristic curve (AUC) were evaluated. Ten-fold leave-one-cohort-internal validation further validated the optimal missing data approach. RESULTS: Among 12,703 biopsies from 10 training cohorts, 3,597 (28%) had clinically significant prostate cancer, compared to 1,757 of 5,540 (32%) in the external validation cohort. In external validation, the available cases method that pooled individual patient data containing all risk factors input by an end-user had best CIL, under-predicting risks as percentages by 2.9% on average, and obtained an AUC of 75.7%. Imputation had the worst CIL (-13.3%). The available cases method was further validated as optimal in internal cross-validation and thus used for development of an online risk tool. For end-users of the risk tool, two risk factors were mandatory: serum prostate-specific antigen (PSA) and age, and ten were optional: digital rectal exam, prostate volume, prior negative biopsy, 5-alpha-reductase-inhibitor use, prior PSA screen, African ancestry, Hispanic ethnicity, first-degree prostate-, breast-, and second-degree prostate-cancer family history. CONCLUSION: Developers of clinical risk prediction tools should optimize use of available data and sources even in the presence of high amounts of missing data and offer options for users with missing risk factors.

Survival after minimally invasive vs. open radical nephrectomy for stage I and II renal cell carcinoma.

BACKGROUND: A recently reported phase III randomized trial comparing open and minimally invasive hysterectomy showed significantly higher rates of local recurrence after minimally invasive surgery (MIS) for cervical cancer. This raised concerns regarding patterns of recurrences and survival after MIS in general. This study aims to determine the effect of MIS on all-cause mortality among patients undergoing radical nephrectomy for Stage I and II renal cell carcinoma (RCC). METHODS: We utilized the National Cancer Database to identify patients diagnosed with clinical stage I-II RCCs between 2010 and 2013. Patients for whom a laparoscopic or robotic radical nephrectomy was attempted were compared to patients who underwent open radical nephrectomy (ORN). Adjusted regression models with inverse probability propensity score weighting (IPW) were utilized to identify independent predictors of receiving MIS. All-cause mortality rates were compared using IPW survival functions and log-rank tests. Adjusted Cox proportional hazard models were fitted to determine independent predictors of OS. RESULTS: 27,642 patients were identified; 11,524 (41.7%) had MIS, while 16,118 (58.3%) had ORN. Kaplan-Meier survival curves in the IPW cohort showed significant OS advantage for patients who underwent MIS (p < 0.001). Furthermore, length of hospital stays (3 vs. 4 days), 30 day readmission rates (2.4 vs. 2.87%), 30 day (0.53 vs. 0.96%) and 90 day mortality rates (1.04 vs. 1.77%) were significantly higher in the ORN group (p < 0.001). CONCLUSIONS: MIS was associated with better OS outcomes compared to ORN for stage I and II RCC. In addition, MIS had lower post-operative readmission, 30- and 90 day mortality rates.

Restriction Spectrum Imaging-Magnetic Resonance Imaging to Improve Prostate Cancer Imaging in Men on Active Surveillance.

PURPOSE: Restriction spectrum imaging-magnetic resonance imaging is a short duration enhanced diffusion-weighted technique that seeks to standardize sequences and predict upgrading. We test this technology for active surveillance biopsies. Our objective is to investigate the utility of restriction spectrum imaging-magnetic resonance imaging to improve upgrading detection in a prostate cancer active surveillance cohort. MATERIALS AND METHODS: We prospectively enrolled men on active surveillance undergoing repeat biopsy from January 2016 to June 2019. Subjects underwent prostate multiparametric magnetic resonance imaging and restriction spectrum imaging-magnetic resonance imaging reviewed by a urological radiologist for PI-RADS® scored lesions, followed by magnetic resonance imaging-guided prostate biopsy by a urologist. Restriction spectrum imaging-magnetic resonance imaging analysis with proprietary research software (CorTechs Labs, San Diego, California) generated a restricted signal map. We compared the restricted signal map and apparent diffusion coefficient values using T-test, ANOVA, and logistic regression analyses for prediction of upgrading. RESULTS: Of 123 enrolled men we identified 74 restriction spectrum imaging-magnetic resonance imaging regions of interest (targeted lesions) in 110 subjects, with 105 subjects completing biopsy. The restricted signal map was significant per PI-RADS score for true-positive lesion detection (mean difference 28, SD 0.7, p=0.001), and better than apparent diffusion coefficient (mean difference -15, SD 55, p=0.6). Restriction spectrum imaging generated restricted signal map values >50 improved sensitivity, specificity, positive predictive value and negative predictive value (81.0%, 81.8%, 54.2% and 94.2%) over PI-RADS ≥3 (71.4%, 38.9%, 23.7% and 83.7%, respectively) for Gleason upgrading. Overall restriction spectrum imaging is able to improve the AUC of 0.70 (95% CI 0.49-0.92, p=0.03) to 0.90 (95% CI 0.82-0.98, p <0.001). CONCLUSIONS: Restriction spectrum imaging-magnetic resonance imaging enhances the standard PI-RADS system by providing a noninvasive radiological biomarker to predict upgrading in active surveillance.

Comparison of rectal swab, glove tip, and participant-collected stool techniques for gut microbiome sampling.

BACKGROUND: Studies of the gut microbiome are becoming increasingly important. Such studies require stool collections that can be processed or frozen in a timely manner so as not to alter the microbial content. Due to the logistical difficulties of home-based stool collection, there has been a challenge in selecting the appropriate sample collection technique and comparing results from different microbiome studies. Thus, we compared stool collection and two alternative clinic-based fecal microbiome collection techniques, including a newer glove-based collection method. RESULTS: We prospectively enrolled 22 adult men from our prostate cancer screening cohort SABOR (San Antonio Biomarkers of Risk for prostate cancer) in San Antonio, TX, from 8/2018 to 4/2019. A rectal swab and glove tip sample were collected from each participant during a one-time visit to our clinics. A single stool sample was collected at the participant's home. DNA was isolated from the fecal material and 16 s rRNA sequencing of the V1-V2 and V3-V4 regions was performed. We found the gut microbiome to be similar in richness and evenness, noting no differences in alpha diversity among the collection methods. The stool collection method, which remains the gold-standard method for the gut microbiome, proved to have different community composition compared to swab and glove tip techniques (p< 0.001) as measured by Bray-Curtis and unifrac distances. There were no significant differences in between the swab and glove tip samples with regard to beta diversity (p> 0.05). Despite differences between home-based stool and office-based fecal collection methods, we noted that the distance metrics for the three methods cluster by participant indicating within-person similarities. Additionally, no taxa differed among the methods in a Linear Discriminant Analysis Effect Size (LEfSe) analysis comparing all-against-all sampling methods. CONCLUSION: The glove tip method provides similar gut microbiome results as rectal swab and stool microbiome collection techniques. The addition of a new office-based collection technique could help easy and practical implementation of gut microbiome research studies and clinical practice.

Evidence for 2-Methoxyestradiol-Mediated Inhibition of Receptor Tyrosine Kinase RON in the Management of Prostate Cancer.

2-Methoxyestradiol (2-ME2) possesses anti-tumorigenic activities in multiple tumor models with acceptable tolerability profile in humans. Incomplete understanding of the mechanism has hindered its development as an anti-tumorigenic compound. We have identified for the first-time macrophage stimulatory protein 1 receptor (MST1R) as a potential target of 2-ME2 in prostate cancer cells. Human tissue validation studies show that MST1R (a.k.a RON) protein levels are significantly elevated in prostate cancer tissues compared to adjacent normal/benign glands. Serum levels of macrophage stimulatory protein (MSP), a ligand for RON, is not only associated with the risk of disease recurrence, but also significantly elevated in samples from African American patients. 2-ME2 treatment inhibited mechanical properties such as adhesion and elasticity that are associated with epithelial mesenchymal transition by downregulating mRNA expression and protein levels of MST1R in prostate cancer cell lines. Intervention with 2-ME2 significantly reduced tumor burden in mice. Notably, global metabolomic profiling studies identified significantly higher circulating levels of bile acids in castrated animals that were decreased with 2-ME2 intervention. In summary, findings presented in this manuscript identified MSP as a potential marker for predicting biochemical recurrence and suggest repurposing 2-ME2 to target RON signaling may be a potential therapeutic modality for prostate cancer.

Magnetic Resonance Imaging for the Detection of High Grade Cancer in the Canary Prostate Active Surveillance Study.

PURPOSE: We investigated the ability of prostate magnetic resonance imaging to detect Gleason Grade Group 2 or greater cancer in a standardized, multi-institutional active surveillance cohort. MATERIALS AND METHODS: We evaluated men enrolled in Canary Prostate Active Surveillance Study with Gleason Grade Group less than 2 and who underwent biopsy within 12 months of multiparametric magnetic resonance imaging. Our primary outcome was biopsy reclassification to Gleason Grade Group 2 or greater. We evaluated the performance of magnetic resonance imaging PI-RADS® score and clinical factors. Multivariable logistic regression models were fit with magnetic resonance imaging and clinical factors and used to perform receiver operating curve analyses. RESULTS: There were 361 participants with 395 prostate magnetic resonance imaging studies with a median followup of 4.1 (IQR 2.0-7.6) years. Overall 108 (27%) biopsies showed reclassification. Defining positive magnetic resonance imaging as PI-RADS 3-5, the negative predictive value and positive predictive value for detecting Gleason Grade Group 2 or greater cancer was 83% (95% CI 76-90) and 31% (95% CI 26-37), respectively. PI-RADS was significantly associated with reclassification (PI-RADS 5 vs 1 and 2 OR 2.71, 95% CI 1.21-6.17, p=0.016) in a multivariable model but did not improve upon a model with only clinical factors (AUC 0.768 vs 0.762). In 194 fusion biopsies higher grade cancer was found in targeted cores in 21 (11%) instances, while 25 (13%) had higher grade cancer in the systematic cores. CONCLUSIONS: This study adds the largest cohort data to the body of literature for magnetic resonance imaging in active surveillance, recommending systematic biopsy in patients with negative magnetic resonance imaging and the inclusion of systematic biopsy in patients with positive magnetic resonance imaging.

Systematic Review of Current Ultrasound Use in Education and Simulation in the Field of Urology.

PURPOSE OF THE REVIEW: We investigate articles in the literature published in the last 5 years (2014-2019) regarding ultrasound education in the specialty of urology. RECENT FINDINGS: Ultrasound has been touted as the modern day stethoscope. Medical educational governing bodies have encouraged the incorporation of ultrasound in medical school education. However, in this review, we find that there are gaps in educational opportunities and standardization in residency and continuing education for urology practitioners. We have identified several new tools for procedure-specific training published in the last 5 years including MRI fusion prostate biopsy and percutaneous nephrolithotomy. New technology is being fused with traditional ultrasound training to provide procedure-specific ultrasound knowledge. There is a need to incorporate new technology and standards into resident and continuing medical education.

Development and implementation of competency-based assessment for urological ultrasound training using SonoSim: A preliminary evaluation.

INTRODUCTION: Urology residents are encouraged to learn ultrasound (U/S) imaging, yet there are few tools available for teaching and assessing a resident`s competence. The aim of this study was to test the new SonoSim LiveScan® and to propose a competency-based assessment model for the urology graduate medical education. MATERIALS AND METHODS: Urology residents attended an interactive training session covering the urological U/S techniques guided by the assessment model developed by the authors. Faculty members evaluated the residents using defined objectives, and the residents were surveyed on their comfort level for performing each of the model tasks. A subset of the residents then underwent a structured testing using the SonoSim LiveScan device 6 months following the training. The model developed assessed: general U/S setup, structure identification, and pathologic clinical scenarios. RESULTS: The residents felt most comfortable in identifying the bladder (4.73/5) and the kidneys (4.53/5) during the training sessions. They felt least comfortable while testing for total ureteric obstruction (3.13/5). All the residents were confident that additional U/S training sessions would improve their comfort level in performing the assessed objectives. Resident`s assessment performed at 6 months had a median test score of 15.5/20 and the assessment scores increased with resident seniority. Self-reported comfort, however, did not seem to correlate with seniority. In general, the residents felt that the SonoSim device was highly functional (4.4/5) and the pathologic assessments in particular were very helpful (4.4/5). CONCLUSIONS: Through pilot testing, we propose that a competency-based assessment used with the SonoSim LiveScan could guide the resident`s education through the acquisition of U/S skills and warrants testing in a larger cohort.

Multi-cohort modeling strategies for scalable globally accessible prostate cancer risk tools.

BACKGROUND: Online clinical risk prediction tools built on data from multiple cohorts are increasingly being utilized for contemporary doctor-patient decision-making and validation. This report outlines a comprehensive data science strategy for building such tools with application to the Prostate Biopsy Collaborative Group prostate cancer risk prediction tool. METHODS: We created models for high-grade prostate cancer risk using six established risk factors. The data comprised 8492 prostate biopsies collected from ten institutions, 2 in Europe and 8 across North America. We calculated area under the receiver operating characteristic curve (AUC) for discrimination, the Hosmer-Lemeshow test statistic (HLS) for calibration and the clinical net benefit at risk threshold 15%. We implemented several internal cross-validation schemes to assess the influence of modeling method and individual cohort on validation performance. RESULTS: High-grade disease prevalence ranged from 18% in Zurich (1863 biopsies) to 39% in UT Health San Antonio (899 biopsies). Visualization revealed outliers in terms of risk factors, including San Juan VA (51% abnormal digital rectal exam), Durham VA (63% African American), and Zurich (2.8% family history). Exclusion of any cohort did not significantly affect the AUC or HLS, nor did the choice of prediction model (pooled, random-effects, meta-analysis). Excluding the lowest-prevalence Zurich cohort from training sets did not statistically significantly change the validation metrics for any of the individual cohorts, except for Sunnybrook, where the effect on the AUC was minimal. Therefore the final multivariable logistic model was built by pooling the data from all cohorts using logistic regression. Higher prostate-specific antigen and age, abnormal digital rectal exam, African ancestry and a family history of prostate cancer increased risk of high-grade prostate cancer, while a history of a prior negative prostate biopsy decreased risk (all p-values < 0.004). CONCLUSIONS: We have outlined a multi-cohort model-building internal validation strategy for developing globally accessible and scalable risk prediction tools.

The Microbiome and Prostate Cancer Risk.

PURPOSE OF THE REVIEW: There is an abundance of evidence that the human microbiome plays an important and nuanced role in controlling human metabolism, immunity, and cancer. Herein we aim to review the most current research looking at prostate cancer and its link with the gut and genitourinary microbiome. There is now a host of evidence for a unique genitourinary (GU) microbiome. The prostate microbiota, to include viral, bacterial, fungal, and parasitic contributions, as assessed from formalin-fixed tissue is described nicely in the study by Banerjee et al. Further hierarchical analysis by this group found a unique microbiome signature for higher Gleason score cancers and validation PCR studies noted a marked number of viral genomic insertions into host DNA. Shretha et al. also recently established unique GU microbiomes in patients with prostate cancer or benign prostate pathology based on urine samples. The gut microbiome likely also has an indirect but significant role in prostate cancer development and treatment. Liss et al. and Golombos et al. found significant associations between specific gut microbiota and prostate cancer. Interestingly, the balance of inflammatory and anti-inflammatory bacterial lipopolysaccharides, production of bile salts, and metabolism of dietary fiber to short chain fatty acids all likely play important roles in creating systemic pro- or anti-carcinogenic states. In terms of prostate cancer treatment effects, Sfanos et al. noted a unique microbial signature in patients undergoing oral androgen deprivation therapy (ADT) as compared with prostate cancer patients not on ADT. Patients undergoing ADT also had enrichment of bacterial metabolic pathways promoting androgen synthesis. Together, these studies have identified a unique GU microbiome and linked both the GU microbiome and unique gut microbial signatures with prostate cancer and prostate cancer treatments. Whether this information can be used in cancer prevention, treatment, or diagnosis are areas of ongoing and active research.

Targeted Antimicrobial Prophylaxis Does Not Always Prevent Sepsis after Transrectal Prostate Biopsy.

PURPOSE: We compared the effectiveness of targeted prophylaxis to augmented empirical prophylaxis and single agent empirical prophylaxis to prevent sepsis after transrectal prostate biopsy. MATERIALS AND METHODS: We retrospectively reviewed the records of transrectal prostate biopsies performed during 3 years at 13 Southern California Kaiser Permanente® departments of urology. Targeted prophylaxis was guided by rectal culture bacterial susceptibility for use of a single prophylactic antibiotic while for empirical prophylaxis 1 antibiotic (single agent empirical prophylaxis) or multiple antibiotics (augmented empirical prophylaxis) were given according to the usual practice of the urologist. Sepsis was the primary outcome analyzed. RESULTS: We reviewed 15,236 transrectal prostate biopsy cases. Targeted prophylaxis, single agent empirical prophylaxis and augmented empirical prophylaxis were administered in 26%, 58% and 16% of cases, respectively. The overall incidence of post-biopsy sepsis was 0.64%. On multivariable analysis there was no significant difference in the rate of post-biopsy sepsis after targeted prophylaxis compared to empirical prophylaxis (single agent and augmented empirical prophylaxis together) (OR 0.86, 95% CI 0.53-1.41, p = 0.561). However, on subanalysis augmented empirical prophylaxis showed a significantly lower incidence of sepsis than single agent empirical or targeted prophylaxis (OR 0.35, 95% CI 0.16-0.76, p = 0.008). Based on blood and urine cultures 38% of the patients with sepsis after transrectal prostate biopsy had been given the correct prophylactic antibiotic prior to biopsy. On multivariable analysis Asian/Pacific Islander or Hispanic/Latino ethnicity was associated with a higher incidence of harboring fluoroquinolone resistant bacteria on rectal swab cultures. CONCLUSIONS: This large retrospective study showed that augmented empirical prophylaxis was statistically superior to single agent empirical and targeted prophylaxis. Sepsis developed in a significant number of patients despite being given a prophylactic antibiotic to which the sepsis causing bacteria were sensitive.

The effectiveness of targeted relative to empiric prophylaxis on infectious complications after transrectal ultrasound-guided prostate biopsy: a meta-analysis.

PURPOSE: Rectal culture screening for fluoroquinolone (FQ)-resistant Enterobacteriaceae before transrectal ultrasound guided prostate (TRUSPB) biopsy and targeted antibiotic prophylaxis (TAP) may decrease post-TRUSPB infection rates compared to empiric (EAP) regimens. The objective of this study was to evaluate the effectiveness of targeted relative to empiric prophylaxis regimens on rates of infectious complications after TRUSPB and to determine the baseline prevalence of FQ resistance based on prior rectal swabs. METHODS: An electronic search within literature databases including EMBASE and Web of Science (all databases) for articles assessing TAP as an approach to TRUSPB prophylaxis was conducted. Quality assessment was performed using the Hoy instrument. Meta-analysis was performed using MetaXL 5.3. RESULTS: From 15 studies (eight retrospective and seven prospective) representing 12,320 participants, infectious complication incidence was 3.4% in EAP and 0.8% in TAP patients. The number needed to treat with TAP to avoid one more infection when compared to the EAP group was 39. Effect sizes were homogeneous. Prevalence of FQ resistance showed low (15%) and high (28%) subgroups, likely due to region of origin (within and outside USA, respectively). CONCLUSIONS: Rectal culture prior to TRUSPB and use of TAP adjusts for endemic FQ resistance and is associated with less infectious complications and resulting morbidity when compared to EAP. Overtreatment associated with augmented prophylaxis approaches may be reduced as a result. Further prospective assessment and cost-benefit analyses are required before widespread implementation can be recommended.

Prostate cancer prevention with 5-alpha reductase inhibitors: concepts and controversies.

PURPOSE OF REVIEW: We review the concepts surrounding prostate cancer prevention strategies with 5-alpha reductase inhibitors (5-ARIs) and the controversies associated with their use. RECENT FINDINGS: Updated data have shown no increased risk of death from the diagnosis of higher risk cancer; however, 5-ARIs remain controversial and not approved for prostate cancer prevention. SUMMARY: The main theme of the review identifies the success of reducing insignificant prostate cancer and the controversy with the increased association of higher risk prostate cancer by approximately 20%. The reduction was shown to be most significant reduction in low-grade prostate cancer. The initial concern about 5-ARI use was that it could potentially increase high-risk prostate cancer leading to higher mortality in those men. Higher mortality has not been seen in follow-up data; however, 5-ARIs continue to have a black box warning and are not approved for prostate cancer prevention.