Determination of variability due to biological and technical variation in urinary extracellular vesicles as a crucial step in biomarker discovery studies.

Urinary extracellular vesicles (EVs) are an attractive source of biomarkers for urological diseases. A crucial step in biomarker discovery studies is the determination of the variation parameters to perform a sample size calculation. In this way, a biomarker discovery study with sufficient statistical power can be performed to obtain biologically significant biomarkers. Here, a variation study was performed on both the protein and lipid content of urinary EVs of healthy individuals, aged between 52 and 69 years. Ultrafiltration (UF) in combination with size exclusion chromatography (SEC) was used to isolate the EVs from urine. Different experimental variation set-ups were used in this variation study. The calculated standard deviations (SDs) of the 90% least variable peptides and lipids did not exceed 2 and 1.2, respectively. These parameters can be used in a sample size calculation for a well-designed biomarker discovery study at the cargo of EVs.

Intravascular double J stent migration: A case report, review, and management algorithm.

A double J stent (DJS) is the main therapy for ureteral obstruction when conservative treatment fails. Antegrade migration in the bladder - or retrograde migration in the ureter - are well-known complications. We present a case with intravascular migration of a DJS into the inferior vena cava. Inferior venocavagraphy confirmed the position of the stent, and thrombus formation was excluded at its tip. The stent was retracted endoscopically. After the procedure, limited contrast leakage was seen at the perforation site on venography. The current available literature is reviewed. Based on this, a management algorithm is drawn up.

Bladder Cancer Diagnosis and Follow-Up: The Current Status and Possible Role of Extracellular Vesicles.

Diagnostic methods currently used for bladder cancer are cystoscopy and urine cytology. Cystoscopy is an invasive tool and has low sensitivity for carcinoma in situ. Urine cytology is non-invasive, is a low-cost method, and has a high specificity but low sensitivity for low-grade urothelial tumors. Despite the search for urinary biomarkers for the early and non-invasive detection of bladder cancer, no biomarkers are used at the present in daily clinical practice. Extracellular vesicles (EVs) have been recently studied as a promising source of biomarkers because of their role in intercellular communication and tumor progression. In this review, we give an overview of Food and Drug Administration (FDA)-approved urine tests to detect bladder cancer and why their use is not widespread in clinical practice. We also include non-FDA approved urinary biomarkers in this review. We describe the role of EVs in bladder cancer and their possible role as biomarkers for the diagnosis and follow-up of bladder cancer patients. We review recently discovered EV-derived biomarkers for the diagnosis of bladder cancer.

TP53 Outperforms Other Androgen Receptor Biomarkers to Predict Abiraterone or Enzalutamide Outcome in Metastatic Castration-Resistant Prostate Cancer.

PURPOSE: To infer the prognostic value of simultaneous androgen receptor (AR) and TP53 profiling in liquid biopsies from patients with metastatic castration-resistant prostate cancer (mCRPC) starting a new line of AR signaling inhibitors (ARSi).Experimental Design: Between March 2014 and April 2017, we recruited patients with mCRPC (n = 168) prior to ARSi in a cohort study encompassing 10 European centers. Blood samples were collected for comprehensive profiling of CellSearch-enriched circulating tumor cells (CTC) and circulating tumor DNA (ctDNA). Targeted CTC RNA sequencing (RNA-seq) allowed the detection of eight AR splice variants (ARV). Low-pass whole-genome and targeted gene-body sequencing of AR and TP53 was applied to identify amplifications, loss of heterozygosity, mutations, and structural rearrangements in ctDNA. Clinical or radiologic progression-free survival (PFS) was estimated by Kaplan-Meier analysis, and independent associations were determined using multivariable Cox regression models. RESULTS: Overall, no single AR perturbation remained associated with adverse prognosis after multivariable analysis. Instead, tumor burden estimates (CTC counts, ctDNA fraction, and visceral metastases) were significantly associated with PFS. TP53 inactivation harbored independent prognostic value [HR 1.88; 95% confidence interval (CI), 1.18-3.00; P = 0.008], and outperformed ARV expression and detection of genomic AR alterations. Using Cox coefficient analysis of clinical parameters and TP53 status, we identified three prognostic groups with differing PFS estimates (median, 14.7 vs. 7.51 vs. 2.62 months; P < 0.0001), which was validated in an independent mCRPC cohort (n = 202) starting first-line ARSi (median, 14.3 vs. 6.39 vs. 2.23 months; P < 0.0001). CONCLUSIONS: In an all-comer cohort, tumor burden estimates and TP53 outperform any AR perturbation to infer prognosis.See related commentary by Rebello et al., p. 1699.

Cell-free DNA profiling of metastatic prostate cancer reveals microsatellite instability, structural rearrangements and clonal hematopoiesis.

BACKGROUND: There are multiple existing and emerging therapeutic avenues for metastatic prostate cancer, with a common denominator, which is the need for predictive biomarkers. Circulating tumor DNA (ctDNA) has the potential to cost-efficiently accelerate precision medicine trials to improve clinical efficacy and diminish costs and toxicity. However, comprehensive ctDNA profiling in metastatic prostate cancer to date has been limited. METHODS: A combination of targeted and low-pass whole genome sequencing was performed on plasma cell-free DNA and matched white blood cell germline DNA in 364 blood samples from 217 metastatic prostate cancer patients. RESULTS: ctDNA was detected in 85.9% of baseline samples, correlated to line of therapy and was mirrored by circulating tumor cell enumeration of synchronous blood samples. Comprehensive profiling of the androgen receptor (AR) revealed a continuous increase in the fraction of patients with intra-AR structural variation, from 15.4% during first-line metastatic castration-resistant prostate cancer therapy to 45.2% in fourth line, indicating a continuous evolution of AR during the course of the disease. Patients displayed frequent alterations in DNA repair deficiency genes (18.0%). Additionally, the microsatellite instability phenotype was identified in 3.81% of eligible samples (≥ 0.1 ctDNA fraction). Sequencing of non-repetitive intronic and exonic regions of PTEN, RB1, and TP53 detected biallelic inactivation in 47.5%, 20.3%, and 44.1% of samples with ≥ 0.2 ctDNA fraction, respectively. Only one patient carried a clonal high-impact variant without a detectable second hit. Intronic high-impact structural variation was twice as common as exonic mutations in PTEN and RB1. Finally, 14.6% of patients presented false positive variants due to clonal hematopoiesis, commonly ignored in commercially available assays. CONCLUSIONS: ctDNA profiles appear to mirror the genomic landscape of metastatic prostate cancer tissue and may cost-efficiently provide somatic information in clinical trials designed to identify predictive biomarkers. However, intronic sequencing of the interrogated tumor suppressors challenges the ubiquitous focus on coding regions and is vital, together with profiling of synchronous white blood cells, to minimize erroneous assignments which in turn may confound results and impede true associations in clinical trials.

Effects of a six-month supervised physical exercise program on physical and cardio-metabolic profile and quality of life in patients with prostate cancer on androgen deprivation therapy: a pilot and feasibility study.

INTRODUCTION: To evaluate the effect of a six-month supervised physical exercise program on the physical and cardio-metabolic profile and quality of life in patients with prostate cancer on androgen deprivation therapy. MATERIAL AND METHODS: Twenty-seven patients with prostate cancer on androgen deprivation therapy were included in a physical exercise program. The program consisted of supervised physical exercises during a six-month period (two hours, twice a week). The exercise program contained moderate to high intensity aerobic and resistance exercises: cycling, walking or jogging for 45 minutes at an intensity of ±80% of the individual maximum heart rate, followed by resistance exercises targeting the major lower and upper body muscles. All patients were assessed prior to the exercise program, including anthropometrical parameters, blood analysis, quality of life and physical fitness. Blood analysis was repeated at a three-month follow-up. Anthropometrical parameters, physical fitness and quality of life were recorded at a three-, six- and nine-month follow-up. RESULTS: A positive effect on physical performance, muscular strength and quality of life was seen. The applied physical exercise program was well tolerated and characterized by a high satisfaction rate. An alarming issue of remarkably unfavorable baseline cardio-metabolic profile was revealed within our study population. CONCLUSIONS: Our data indicates that a six-month supervised physical exercise program can be beneficial in preventing androgen deprivation therapy-related side effects in patients with prostate cancer. We emphasize the importance of screening for cardio-metabolic risk factors in patients who are treated with androgen deprivation therapy.

Circulating tumor cells and survival in abiraterone- and enzalutamide-treated patients with castration-resistant prostate cancer.

BACKGROUND: The outcome to treatment administered to patients with metastatic castration-resistant prostate cancer (mCRPC) greatly differs between individuals, underlining the need for biomarkers guiding treatment decision making. OBJECTIVE: To investigate the prognostic value of circulating tumor cell (CTC) enumeration and dynamics, in the context of second-line endocrine therapies (ie, abiraterone acetate or enzalutamide), irrespective of prior systemic therapies. DESIGN, SETTINGS, AND PARTICIPANTS: In a prospective, multicentre study blood samples for CTC enumeration were collected from patients with mCRPC at baseline (n = 174). In patients who responded for minimally 10-12 weeks a follow-up sample was collected. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: For baseline analysis, patients were stratified in <5 or ≥5 CTCs/7.5 mL, whereas for the analysis of CTC dynamics at 10-12 weeks, in patients with stable, increasing or decreasing CTC counts. Progression-free survival (PFS), overall survival (OS), and PSA changes at 10-12 weeks were compared between groups. RESULTS: Patients demonstrating increasing CTCs on therapy had a shorter median PFS (4.03 vs 12.98 vs 13.67 months, HR 3.6, 95%CI 1.9-6.8; P < 0.0001) and OS (11.2 months vs not reached, HR 9.5, 95%CI 3.7-24; P < 0.0001), compared to patients with decreasing or stable CTCs. Multivariable Cox regression showed that prior chemotherapy (HR 4.1, 95%CI 1.9-8.9; P = 0.0003), a high baseline CTC count (HR 1.5, 95%CI 1.2-1.9; P = 0.002) and increasing CTCs at follow-up (HR 3.3, 95%CI 1.4-7.6; P = 0.005) were independent predictors of worse PFS. Previous chemotherapy (HR 7, 95%CI 1.9-25; P = 0.003), high baseline CTC counts (HR 2.2, 95%CI 1.4-3.7; P = 0.002) and increasing CTCs during therapy (HR 4.6, 95%CI 1.4-15; P = 0.01) were independently associated with shorter OS. ≥30% and ≥50% PSA responses less frequently occurred in patients with CTC inclines at 10-12 weeks on therapy (χ2 test: P < 0.01). CONCLUSIONS: CTC dynamics during therapy are associated with PSA response and provide independent clinical prognostication over PSA declines. Hence the study demonstrates the pharmacodynamic properties of CTCs.

Functional bladder capacity after bladder biofeedback predicts long-term outcome in children with nocturnal enuresis.

OBJECTIVE: We previously reported a 70% cure rate for bladder biofeedback in children with primary nocturnal enuresis associated with small bladder capacity and detrusor instability. In this paper we report on bladder capacity and incidence of enuresis after 60 months of follow-up and discuss the role of decreased bladder capacity in nocturnal enuresis. MATERIAL AND METHODS: We prospectively evaluated 21 boys and 3 girls (mean age 10.4 years) treated with bladder biofeedback between October 1993 and July 1995. Baseline bladder capacity and capacity at the end of treatment and at 60 months follow-up were determined from a micturition chart. RESULTS: At the end of primary treatment 17/24 patients had stopped bedwetting. In 4/17 responders and 4/7 non-responders the bladder capacity was <90% of normal for age. At 60 months, 4 patients had been lost to follow-up, 15 were dry at night and 4 continued bedwetting. One patient underwent surgery and was excluded from the study. Only 2/15 dry patients but 3/4 patients with persistent nocturnal enuresis had a bladder capacity of <90% of normal. CONCLUSIONS: Bladder biofeedback can be successfully used to treat children with refractory nocturnal enuresis associated with small bladder capacity and unstable detrusor. Normalization of bladder capacity and continuous growth of the bladder in order to keep the capacity normal would seem to be crucial to the long-term resolution of bedwetting in this select patient population.