Benchmarking blood collection tubes and processing intervals for extracellular vesicle performance metrics.

The analysis of extracellular vesicles (EV) in blood samples is under intense investigation and holds the potential to deliver clinically meaningful biomarkers for health and disease. Technical variation must be minimized to confidently assess EV-associated biomarkers, but the impact of pre-analytics on EV characteristics in blood samples remains minimally explored. We present the results from the first large-scale EV Blood Benchmarking (EVBB) study in which we systematically compared 11 blood collection tubes (BCT; six preservation and five non-preservation) and three blood processing intervals (BPI; 1, 8 and 72 h) on defined performance metrics (n = 9). The EVBB study identifies a significant impact of multiple BCT and BPI on a diverse set of metrics reflecting blood sample quality, ex-vivo generation of blood-cell derived EV, EV recovery and EV-associated molecular signatures. The results assist the informed selection of the optimal BCT and BPI for EV analysis. The proposed metrics serve as a framework to guide future research on pre-analytics and further support methodological standardization of EV studies.

Removal of platelets from blood plasma to improve the quality of extracellular vesicle research.

BACKGROUND: Blood plasma is commonly used for biomarker research of extracellular vesicles (EVs). Removing all cells prior to analysis of EVs is essential. OBJECTIVES: We therefore studied the efficacy of the most commonly used centrifugation protocol to prepare cell-free plasma. METHODS: Plasma was prepared according to the double centrifugation protocol of the International Society on Thrombosis and Haemostasis (ISTH) in three independent studies. The concentrations of platelets, platelet-derived EVs, and erythrocyte-derived EVs were measured by calibrated flow cytometry. RESULTS: The mean platelet concentration ranged from 5.1 × 105 /ml to 2.8 × 107 /ml and differed 55-fold between studies. Thus, the ISTH centrifugation protocol does not remove all platelets and results in variation between studies. As the concentration of platelet-derived EVs and platelets correlates linearly (R2  = .56), and the volume fraction of EVs and platelets in plasma are similar, the presence of platelets affects downstream analysis. To remove platelets a 0.8-µm polycarbonate filter was used to lower the platelet concentration 146-fold (p = .0013), without affecting the concentration of platelet-derived and erythrocyte-derived EVs (p = .982, p = .742). CONCLUSIONS: To improve the quality of EV research, we recommend (1) measuring and reporting the platelet concentration in plasma used for EV research, or (2) removing platelets by centrifugation followed by filtration.

Multicentre, prospective study on local treatment of metastatic prostate cancer (LoMP study).

OBJECTIVES: To investigate the role of cytoreductive radical prostatectomy in addition to standard of care for patients with newly diagnosed metastatic prostate cancer. MATERIALS AND METHODS: This multicentre, prospective study included asymptomatic patients from 2014 to 2018 (NCT02138721). Cytoreductive radical prostatectomy was offered to all fit patients with resectable tumours, resulting in 40 patients. Standard of care was administered to 40 patients who were ineligible or unwilling to undergo surgery. The primary endpoint was castration resistant cancer-free survival at the time point of ≥50% events. The secondary endpoint was local event-free survival. Kaplan-Meier and Cox regression analyses with propensity-score analysis were applied. RESULTS: After a median (quartiles) follow-up of 35 (24-47) months, 42 patients became castration-resistant or died. The median castration resistant cancer-free survival was 53 (95% confidence interval [CI] 14-92) vs 21 (95% CI 15-27) months for cytoreductive radical prostatectomy compared to standard of care (P = 0.017). The 3-year estimates for local event-free survival were 83% (95% CI 71-95) vs 59% (95% CI 51-67) for cytoreductive radical prostatectomy compared to standard of care (P = 0.012). However, treatment group showed no significance in the multivariable models for castration resistant cancer-free survival (P = 0.5) or local event-free survival (P = 0.3), adjusted for propensity-score analysis. Complications were similar to the non-metastatic setting. Patients undergoing surgery were younger, with lower baseline prostate-specific antigen levels, alkaline phosphatase levels and metastatic burden. CONCLUSION: The present LoMP study was unable to show a difference between the two inclusion groups regarding castration resistant cancer-free survival for asymptomatic patients with newly diagnosed metastatic prostate cancer. These results validate previous evidence that, in well-selected and informed patients, cytoreductive radical prostatectomy is feasible and safe, with corresponding continence rates compared to the non-metastatic, high-risk setting. Whether cytoreductive radical prostatectomy could be a valuable option to achieve good local palliation needs to be further researched. Overall, the role of cytoreductive radical prostatectomy needs to be further explored in randomized studies to correct for potential bias.

Integrins are enriched on aberrantly fucosylated tumour-derived urinary extracellular vesicles.

Urinary extracellular vesicles (uEVs) are enriched with glycosylated proteins which have been extensively studied as putative biomarkers of urological cancers. Here, we characterized the glycosylation and integrin profile of EVs derived from urological cancer cell lines. We used fluorescent europium-doped nanoparticles coated with lectins and antibodies to identify a biomarker combination consisting of integrin subunit alpha 3 (ITGA3) and fucose. In addition, we used the same cancer cell line-derived EVs as analytical standards to assess the sensitivity of the ITGA3-UEA assay. The clinical performance of the ITGA3-UEA assay was analysed using urine samples of various urological pathologies including diagnostically challenging benign prostatic hyperplasia (BPH), prostate cancer (PCa) and bladder cancer (BlCa). The assay can significantly discriminate BlCa from all other patient groups: PCa (9.2-fold; p = 0.00038), BPH (5.5-fold; p = 0.004) and healthy individuals (and 23-fold; p = 0.0001). Our results demonstrate that aberrantly fucosylated uEVs and integrin ITGA3 can be detected with fucose-specific lectin UEA in a simple bioaffinity assay for the detection of BlCa directly from unprocessed urine.

Detection of bladder cancer with aberrantly fucosylated ITGA3.

We describe a simple, non-invasive assay to identify fucosylated-glycoisoform of integrin alpha-3 (ITGA3) directly from unprocessed urine. ITGA3 was detected directly from the urine of bladder cancer (BlCa) (n = 13) and benign prostatic hyperplasia (BPH) (n = 9) patients with the use of lectins coated on europium-doped-nanoparticles (Eu3+-NPs). Lectin Ulex europaeus agglutinin-I (UEA) showed enhanced binding with BlCa-derived ITGA3. The evaluation with individual samples showed that a glycovariant ITGA3-UEA assay could significantly discriminate BlCa from BPH patients (p = 0.007). The detection of aberrantly fucosylated-isoform of ITGA3 from urine can be used to distinguish BlCa from age-matched benign controls in a simple sandwich assay.

Preparation of Multi-omics Grade Extracellular Vesicles by Density-Based Fractionation of Urine.

The multidimensional cargo of extracellular vesicles (EV) released in urine is a reflection of the pathophysiological processes occurring within their cells and tissues of origin in the urogenital system. Here, we describe a step-by-step protocol for density-based separation of urinary EV with high specificity and repeatability. The implementation of integrative omics allows the study of the molecular complexity of highly purified urinary EV, supporting the identification of EV-specific functions and biomarkers. For complete details on the use and execution of this protocol, please refer to Dhondt et al. (2020).

Unravelling the proteomic landscape of extracellular vesicles in prostate cancer by density-based fractionation of urine.

Extracellular vesicles (EV) are increasingly being recognized as important vehicles of intercellular communication and promising diagnostic and prognostic biomarkers in cancer. Despite this enormous clinical potential, the plethora of methods to separate EV from biofluids, providing material of highly variable purity, and lacking knowledge regarding methodological repeatability pose a barrier to clinical translation. Urine is considered an ideal proximal fluid for the study of EV in urological cancers due to its direct contact with the urogenital system. We demonstrate that density-based fractionation of urine by bottom-up Optiprep density gradient centrifugation separates EV and soluble proteins with high specificity and repeatability. Mass spectrometry-based proteomic analysis of urinary EV (uEV) in men with benign and malignant prostate disease allowed us to significantly expand the known human uEV proteome with high specificity and identifies a unique biological profile in prostate cancer not uncovered by the analysis of soluble proteins. In addition, profiling the proteome of EV separated from prostate tumour conditioned medium and matched uEV confirms the specificity of the identified uEV proteome for prostate cancer. Finally, a comparative proteomic analysis with uEV from patients with bladder and renal cancer provided additional evidence of the selective enrichment of protein signatures in uEV reflecting their respective cancer tissues of origin. In conclusion, this study identifies hundreds of previously undetected proteins in uEV of prostate cancer patients and provides a powerful toolbox to map uEV content and contaminants ultimately allowing biomarker discovery in urological cancers.

Intradetrusor onabotulinum-a toxin injections in children with therapy-resistant idiopathic detrusor overactivity. A retrospective study.

INTRODUCTION AND OBJECTIVE: The use of intravesical onabotulinum-A toxin (BoNT-A) injections in the treatment of idiopathic detrusor overactivity has been widely studied in adults [2-5]. However, in pediatric populations, study groups are small, and results are not yet sufficient to support this treatment as a standard practice. The aim of this study is to determine the effectiveness and safety of this treatment in children with non-neurogenic detrusor overactivity, resistant to conservative therapy. MATERIAL AND METHODS: We retrospectively evaluated the effect and safety of the intradetrusor injection of 100 Units (U) of BoNT-A in 257 children with therapy-resistant non-neurogenic detrusor overactivity between May 2003 and August 2017. Outcome parameters were the number of daytime incontinence and enuresis episodes per week and bladder capacity (BC). Treatment outcomes were classified into complete response, partial response, or no response. RESULTS: The database includes 257 children, of which are 102 girls and 155 boys. Median age of first BoNT-A injection was 8 years (range 4-18 years). Of the patients with enuresis, daytime incontinence or both, a complete response was seen in 50%, 45.7%, and 17%, respectively. BC was significantly higher after the first, second, and third injection of 100 U BoNT-A. We estimated that the mean duration of the effect of an injection with a dose of 100 U is around 12 months. After the first injection, one girl (0.4%) developed urinary retention, which required temporary clean intermittent catheterization (CIC). Seventeen patients (6.6%) developed a urinary tract infection. In three patients (1.2%), postoperative vesicoureteral reflux was seen. DISCUSSION: A distinction between the effect on daytime incontinence and enuresis was made. A poorer effect on enuresis in children who suffered from both conditions was observed. Drawbacks of this study are its retrospective design and the lack of anticholinergic treatment standardization before and after BoNT-A injection. CONCLUSION: BoNT-A injection is a potentially effective adjuvant therapy in the treatment of children with therapy-resistant overactive bladder (OAB). Bladder capacity increases significantly after the first, second, and third injections. A better effect on daytime incontinence than on enuresis was seen. Prospective randomized trials with standardization of conservative treatment and symptoms questionnaires are necessary to confirm the beneficial effect of BoNT-A injections on BC and incontinence.

Performance assessment of total RNA sequencing of human biofluids and extracellular vesicles.

RNA profiling has emerged as a powerful tool to investigate the biomarker potential of human biofluids. However, despite enormous interest in extracellular nucleic acids, RNA sequencing methods to quantify the total RNA content outside cells are rare. Here, we evaluate the performance of the SMARTer Stranded Total RNA-Seq method in human platelet-rich plasma, platelet-free plasma, urine, conditioned medium, and extracellular vesicles (EVs) from these biofluids. We found the method to be accurate, precise, compatible with low-input volumes and able to quantify a few thousand genes. We picked up distinct classes of RNA molecules, including mRNA, lncRNA, circRNA, miscRNA and pseudogenes. Notably, the read distribution and gene content drastically differ among biofluids. In conclusion, we are the first to show that the SMARTer method can be used for unbiased unraveling of the complete transcriptome of a wide range of biofluids and their extracellular vesicles.

The generation and use of recombinant extracellular vesicles as biological reference material.

Recent years have seen an increase of extracellular vesicle (EV) research geared towards biological understanding, diagnostics and therapy. However, EV data interpretation remains challenging owing to complexity of biofluids and technical variation introduced during sample preparation and analysis. To understand and mitigate these limitations, we generated trackable recombinant EV (rEV) as a biological reference material. Employing complementary characterization methods, we demonstrate that rEV are stable and bear physical and biochemical traits characteristic of sample EV. Furthermore, rEV can be quantified using fluorescence-, RNA- and protein-based technologies available in routine laboratories. Spiking rEV in biofluids allows recovery efficiencies of commonly implemented EV separation methods to be identified, intra-method and inter-user variability induced by sample handling to be defined, and to normalize and improve sensitivity of EV enumerations. We anticipate that rEV will aid EV-based sample preparation and analysis, data normalization, method development and instrument calibration in various research and biomedical applications.

Abiraterone and spironolactone in prostate cancer: a combination to avoid.

Objectives: Disease progression in metastatic castration-resistant prostate cancer (mCRPC) is dependent on androgen signaling. This case describes the complex adaptive androgen signaling mechanisms in mCRPC and illustrates that caution should be exercised when treating these patients with drugs influencing the androgen axis.Methods: Single case report and review of the literature.Results: We report the case of an 86-year-old man with mCRPC, treated with the secondary antihormonal agent abiraterone acetate. Following association of spironolactone to deal with symptoms related to mineralocorticoid excess, biochemical and radiographic disease progression occurred. Spironolactone was discontinued and 8 months after withdrawal, the patient continues to show a biochemical response to abiraterone.Conclusions: Although spironolactone generally exerts anti-androgenic effects, experimental evidence exists that it acts as an androgen receptor agonist in an androgen-depleted environment, capable of inducing prostate cancer proliferation. This is supported by the observations described in this case report. Therefore, spironolactone should be avoided in prostate cancer patients suffering from treatment-associated side effects of abiraterone.

Importance of metastatic volume in prognostic models to predict survival in newly diagnosed metastatic prostate cancer.

PURPOSE: To explore the prognostic importance of metastatic volume in a contemporary daily practice cohort of patients with newly diagnosed metastatic hormone-naive prostate cancer (mHNPC) and to develop a pragmatic prognostic model to predict survival for these patients. METHODS: Since 2014, 113 patients with newly diagnosed mHNPC were prospectively registered. Statistical analysis was performed using SPSS 25.0™ with two-sided p value < 0.05 indicating statistical significance. Univariate and multivariate cox regression analyses were performed to identify prognostic risk factors. Kaplan-Meier method with log-rank statistics was constructed to analyze difference in survival in the prognostic groups. Model performance was assessed using the Concordance-index (C-index) and cross-validated in R v3.4.1. High-volume mHNPC (HVD) was defined as the presence of visceral metastasis or ≥ 4 bone metastases with ≥ 1 appendicular lesion. RESULTS: Multivariate analysis identified HVD (p = 0.047) and elevated alkaline phosphatase (ALP) (p = 0.018) as independent prognostic risk factors for overall survival (OS). Consequently, three prognostic groups were created: a good (no risk factors), intermediate (1 risk factor) and poor prognosis group (2 risk factors). Median OS for the good, intermediate and poor prognosis group was not reached, 73 and 20 months (95% CI 9-31 months with p < 0.001 and Correspondence-index of 0.78), respectively. CONCLUSIONS: We developed a pragmatic and qualitative prognostic model consisting of three prognostic risk groups for OS in a daily practice cohort of patients with newly diagnosed mHNPC. Independent prognostic risk factors included in the model were HVD and abnormal ALP.

Discovery and validation of a serum microRNA signature to characterize oligo- and polymetastatic prostate cancer: not ready for prime time.

PURPOSE: Patients with oligometastatic prostate cancer (PC) may benefit from metastasis-directed therapy (MDT), delaying disease progression and the start of palliative systemic treatment. However, a significant proportion of oligometastatic PC patients progress to polymetastatic PC within a year following MDT, suggesting an underestimation of the metastatic load by current staging modalities. Molecular markers could help to identify true oligometastatic patients eligible for MDT. METHODS: Patients with asymptomatic biochemical recurrence following primary PC treatment were classified as oligo- or polymetastatic based on 18F-choline PET/CT imaging. Oligometastatic patients had up to three metastases at baseline and did not progress to more than three lesions following MDT or surveillance within 1 year of diagnosis of metastases. Polymetastatic patients had > 3 metastases at baseline or developed > 3 metastases within 1 year following imaging. A model aiming to prospectively distinguish oligo- and polymetastatic PC patients was trained using clinicopathological parameters and serum-derived microRNA expression profiles from a discovery cohort of 20 oligometastatic and 20 polymetastatic PC patients. To confirm the models predictive performance, it was applied on biomarker data obtained from an independent validation cohort of 44 patients with oligometastatic and 39 patients with polymetastatic disease. RESULTS: Oligometastatic PC patients had a more favorable prognosis compared to polymetastatic ones, as defined by a significantly longer median CRPC-free survival (not reached versus 38 months; 95% confidence interval 31-45 months with P < 0.001). Despite the good performance of a predictive model trained on the discovery cohort, with an AUC of 0.833 (0.693-0.973; 95% CI) and a sensitivity of 0.894 (0.714-1.000; 95% CI) for oligometastatic disease, none of the miRNA targets were found to be differentially expressed between oligo- and polymetastatic PC patients in the signature validation cohort. The multivariate model had an AUC of 0.393 (0.534 after cross-validation) and therefore, no predictive ability. CONCLUSIONS: Although PC patients with oligometastatic disease had a more favorable prognosis, no serum-derived biomarkers allowing for prospective discrimination of oligo- and polymetastatic prostate cancer patients could be identified.

Urinary extracellular vesicle biomarkers in urological cancers: From discovery towards clinical implementation.

Urine contains cellular elements, biochemicals, and proteins derived from glomerular filtration of plasma, renal tubule excretion, and urogenital tract secretions that reflect an individual's metabolic and pathophysiologic state. Despite intensive research into the discovery of urinary biomarkers to facilitate early diagnosis, accurate prognosis and prediction of therapy response in urological cancers, none of these markers has reached widespread use. Their implementation into daily clinical practice is hampered by a substantial degree of heterogeneity in performance characteristics and uncertainty about reliability, clinical utility and cost-effectiveness, in addition to several technical limitations. Extracellular vesicles (EV) have raised interest as a potential source of biomarker discovery because of their role in intercellular communication and the resemblance of their molecular content to that of the releasing cells. We review currently used urinary biomarkers in the clinic and attempts that have been made to identify EV-derived biomarkers for urological cancers. In addition, we discuss technical and methodological considerations towards their clinical implementation.

Metastatic burden in newly diagnosed hormone-naive metastatic prostate cancer: Comparing definitions of CHAARTED and LATITUDE trial.

OBJECTIVES: No uniformity exists in the definition of metastatic burden in metastatic hormone-naive prostate cancer (mHNPC) across clinical trials making their comparison challenging. We explored definition agreement and prognostic significance of bulky mHNPC according to the CHAARTED and LATITUDE trial. MATERIALS AND METHODS: Since 2014, 95 patients with newly diagnosed mHNPC were prospectively registered. For this study, they were categorized as having high-volume (HVD) vs. low-volume (LVD) and high-risk (HRD) vs. low-risk disease (LRD) according to the definition of CHAARTED and LATITUDE, respectively. Agreement was tested using Cohen's κ coefficient. The Kaplan-Meier method was used to compare castration-resistant prostate cancer-free survival (CRPC-FS) and overall survival (OS). Prognostic significance was analyzed using Cox regression models. RESULTS: In total, 44 (46%) and 46 (48%) patients showed HVD and HRD, respectively. Cohen's κ coefficient was 0.83 indicating "almost perfect" agreement (P<0.001). Median CRPC-FS was 40 (95% CI: 25-55) vs. 11 months (95% CI: 8-14) for LVD and HVD (P = 0.001); 40 (95% CI: 27-53) vs. 11 months (95% CI: 8-14) for LRD and HRD (P<0.001), respectively. Median OS was not reached vs. 51 months (95% CI: 0-102) for LVD and HVD (P = 0.001); not reached vs. 51 months (95% CI: 2-100) for LRD and HRD (P = 0.003), respectively. The prognostic significance of both definitions remained significant in the multivariate model for CRPC-FS (P = 0.012 and P = 0.003). CONCLUSIONS: There is an excellent agreement between the definitions of bulky mHNPC in the CHAARTED and LATITUDE trial. Both definitions have significant prognostic value for predicting worse CRPC-FS and OS.

Prognostic and Therapeutic Implications of Circulating Androgen Receptor Gene Copy Number in Prostate Cancer Patients Using Droplet Digital Polymerase Chain Reaction.

BACKGROUND: Resistance mechanisms in the androgen receptor (AR) signaling pathway remain key drivers in the progression to castration-resistant prostate cancer (CRPC) and relapse under antihormonal therapy. MATERIALS AND METHODS: We evaluated the circulating AR gene copy number (CN) gain using droplet digital polymerase chain reaction in 21 control and 91 prostate cancer serum samples and its prognostic and therapeutic implications in prostate cancer. RESULTS: In CRPC, AR CN gain was associated with faster progression to CRPC (P = .026), a greater number of previous treatments (P = .045), and previous chemotherapy (P = .016). Comparing patients with and without CN gain, the median progression-free survival (PFS) in the abiraterone subgroup was 1.7 months versus not reached (P = .004), and the median overall survival (OS) was 7 months versus 20.9 months (P = .020). In the enzalutamide subgroup, PFS was 1.7 versus 10.8 months (P = .006), and OS was 6.1 versus 16.5 months (P = .042). In the taxane subgroup, PFS was 3.2 versus 6.5 months (P = .093), and OS was 3.9 months versus not reached (P = .026). The presence of more AR copies correlated with shorter androgen deprivation (P = .002), abiraterone (P = .022), enzalutamide (P = .008), and taxane (P = .039) therapy. CONCLUSION: Circulating AR CN gain predicts for a poor prognosis in CRPC. It is a promising biomarker predetermining rapid CRPC progression and predicting worse abiraterone and enzalutamide outcomes. Furthermore, it is associated with multiple previous treatments and previous chemotherapy.

Confounding factors of ultrafiltration and protein analysis in extracellular vesicle research.

Identification and validation of extracellular vesicle (EV)-associated biomarkers requires robust isolation and characterization protocols. We assessed the impact of some commonly implemented pre-analytical, analytical and post-analytical variables in EV research. Centrifugal filters with different membrane types and pore sizes are used to reduce large volume biofluids prior to EV isolation or to concentrate EVs. We compared five commonly reported filters for their efficiency when using plasma, urine and EV-spiked PBS. Regenerated cellulose membranes with pore size of 10 kDa recovered EVs the most efficient. Less than 40% recovery was achieved with other filters. Next, we analyzed the effect of the type of protein assays to measure EV protein in colorimetric and fluorometric kits. The fluorometric assay Qubit measured low concentration EV and BSA samples the most accurately with the lowest variation among technical and biological replicates. Lastly, we quantified Optiprep remnants in EV samples from density gradient ultracentrifugation and demonstrate that size-exclusion chromatography efficiently removes Optiprep from EVs. In conclusion, choice of centrifugal filters and protein assays confound EV analysis and should be carefully considered to increase efficiency towards biomarker discovery. SEC-based removal of Optiprep remnants from EVs can be considered for downstream applications.

EV-TRACK: transparent reporting and centralizing knowledge in extracellular vesicle research.

We argue that the field of extracellular vesicle (EV) biology needs more transparent reporting to facilitate interpretation and replication of experiments. To achieve this, we describe EV-TRACK, a crowdsourcing knowledgebase (http://evtrack.org) that centralizes EV biology and methodology with the goal of stimulating authors, reviewers, editors and funders to put experimental guidelines into practice.

Whole pelvis radiotherapy for pathological node-positive prostate cancer : Oncological outcome and prognostic factors.

PURPOSE: The goal of this work was to investigate the oncological outcome of whole pelvis radiotherapy (wpRT) in pathologic pelvic lymph node-positive (pN1) prostate cancer (PCa), evaluate the location of relapse, and identify potential prognostic factors. PATIENTS AND METHODS: All patients undergoing pelvic lymph node dissection (PLND) since the year 2000 at a single tertiary care center were evaluated. A total of 154 patients with pN1 PCa were treated with wpRT (39 in an adjuvant setting) and 2-3 years of androgen deprivation therapy (ADT). Kaplan-Meier analysis was performed to estimate biochemical recurrence-free survival (bRFS), clinical progression-free survival (cPFS), and prostate cancer-specific survival (CSS). Uni- and multivariate regression analyses were performed to identify prognostic factors. RESULTS: Estimated bRFS was 67%, cPFS was 71%, and CSS was 96% at 5 years. Median follow-up was 55 months (interquartile range 25-87). Multivariate analysis identified having only 1 positive lymph node, a shorter time between diagnosis and PLND, and older age as independent favorable prognostic factors for biochemical and clinical recurrence. The number of positive lymph nodes was prognostic for CSS (hazard ratio [HR] 1.34, 95% confidence interval 1.17-1.54) and OS (HR 1.22, 95% confidence interval 1.10-1.36). Bone metastases were the most frequent location of PCa relapse (n = 32, 64%). CONCLUSIONS: Patients with pN1 PCa treated with wpRT and 2-3 years ADT have an encouraging 5­year CSS. Understaging of the disease extent may be the most important enemy in definitive pN1 PCa treatment.