UBC® Rapid Test for detection of carcinoma in situ for bladder cancer

New Perspectives on the Role of Liquid Biopsy in Bladder Cancer: Applicability to Precision Medicine

Bladder cancer (BC) is one of the most common tumors in the world. Cystoscopy and tissue biopsy are the standard methods in screening and early diagnosis of suspicious bladder lesions. However, they are invasive procedures that may cause pain and infectious complications. Considering the limitations of both procedures, and the recurrence and resistance to BC treatment, it is necessary to develop a new non-invasive methodology for early diagnosis and multiple evaluations in patients under follow-up for bladder cancer. In recent years, liquid biopsy has proven to be a very useful diagnostic tool for the detection of tumor biomarkers. This non-invasive technique makes it possible to analyze single tumor components released into the peripheral circulation and to monitor tumor progression. Numerous biomarkers are being studied and interesting clinical applications for these in BC are being presented, with promising results in early diagnosis, detection of microscopic disease, and prediction of recurrence and response to treatment.

Comet-FISH analysis of urothelial cells. A screening opportunity for bladder cancer?

INTRODUCTION

Bladder cancer (BCa) is the most frequent cancer of the urinary tract, with more than 500,000 reported cases and nearly 200,000 related deaths yearly. Cystoscopy is the standard examination used for the initial diagnosis and follow-up of BCa in the noninvasive stage. However, the American Cancer Society does not include BCa screening in its list of recommended cancer screenings.

AREAS COVERED

Recently, several urine-based bladder tumor markers (UBBTMs) that identify genomic, transcriptomic, epigenetic, or protein alterations have been introduced, some of which have been approved by the Food and Drug Administration (FDA) to improve its diagnosis and surveillance. Several biomarkers have been found in the tissues and blood of individuals with BCa or predisposed to develop the disease, further enriching our information.

EXPERT OPINION

From a prevention perspective, alkaline Comet-FISH could be a valuable tool with broad potential for clinical application. Furthermore, a comet assay could be more beneficial for diagnosing and monitoring bladder cancer and determining individual susceptibility. Thus, we recommend further studies to understand the potential of this combined assay in the general population as a potential screening test and in patients initiated into the diagnostic process.

The Role of Novel Bladder Cancer Diagnostic and Surveillance Biomarkers-What Should a Urologist Really Know?

The aim of this review is to analyze and describe the current landscape of bladder cancer diagnostic and surveillance biomarkers. We researched the literature from 2016 to November 2021 to find the most promising new molecules and divided them into seven different subgroups based on their function and location in the cell. Although cystoscopy and cytology are still the gold standard for diagnosis and surveillance when it comes to bladder cancer (BCa), their cost is quite a burden for national health systems worldwide. Currently, the research is focused on finding a biomarker that has high negative predictive value (NPV) and can exclude with a certainty the presence of the tumor, considering missing it could be disastrous for the patient. Every subgroup has its own advantages and disadvantages; for example, protein biomarkers cost less than genomic ones, but on the other hand, they seem to be less precise. We tried to simplify this complicated topic as much as possible in order to make it comprehensible to doctors and urologists that are not as familiar with it, as well as encourage them to actively participate in ongoing research.

The Development of Non-Invasive Diagnostic Tools in Bladder Cancer

Bladder cancer is a common urinary tract cancer with a difficult clinical course. With frequent recurrence, patients with a history of bladder cancer often undergo surveillance that involves invasive cystoscopies and biopsies. Not only is this financially burdensome for patients but it is also mentally and physically intensive. Given this predicament, the field has shifted towards the use of non-invasive urinary tests to detect bladder cancer earlier in the disease course and to avoid unnecessary procedures. The first non-invasive test developed was urine cytology; however, that was found to have a low sensitivity, especially for low-grade lesions. There are many tests that are available that utilize common protein biomarkers to enhance the sensitivity of detection. However, many of these tests lack the specificity seen with cytology. With recent technological and research advancements, there are newer detection systems such as RNA sequencing and microfluidics along with novel bladder cancer biomarkers including mRNAs, methylation patterns and exosomes, which have potential to be used in clinical practice. The aim of this review is to highlight established non-invasive bladder cancer diagnostic tests as well as innovative methodologies that are on the horizon for use in bladder cancer detection.

Liquid biopsy in bladder cancer: State of the art and future perspectives

Bladder cancer is the most common malignancy of the urinary tract. Cystoscopy represents the gold standard in the diagnosis of suspicious bladder lesions. However, the procedure is invasive and burdened by pain, discomfort and infective complications. Cytology, which represents an alternative diagnostic possibility is limited by poor sensitivity. Considering the limitations of both procedures, and the necessity to perform multiple evaluations in patients who are in follow-up for bladder cancer, an improved non-invasive methodology is required in the clinical management of this disease. Liquid biopsy, e.g. the detection of clinical biomarkers in urine, represent a promising novel and non-invasive approach that could overcome those limitations and be integrated into the current clinical practice. The aim of this review is to summarize the state of the art of this approach and the latest novelties regarding detection, prognosis and surveillance of bladder cancer.

Trends in urine biomarker discovery for urothelial bladder cancer: DNA, RNA, or protein?

Urothelial bladder cancer is a complex disease displaying a landscape of heterogenous molecular subtypes, mutation profiles and clinical presentations. Diagnosis and surveillance rely on flexible cystoscopy which has high accuracy, albeit accompanied by a high-cost burden for healthcare providers and discomfort for patients. Advances in "omic" technologies and computational biology have provided insights into the molecular pathogenesis of bladder cancer and provided powerful tools to identify markers for disease detection, risk stratification, and predicting responses to therapy. To date, numerous attempts have been made to discover and validate diagnostic biomarkers that could be deployed as an adjunct to the cystoscopic diagnosis and long-term surveillance of bladder cancer. We report a comprehensive literature analysis using PubMed to assess the changing trends in investigating DNA, RNA, or proteins as diagnostic urinary biomarkers over a period of 5 decades: 1970-2020. A gradual shift has been observed in research away from protein biomarkers to nucleic acids including different classes of RNA, and DNA methylation and mutation markers. Until 2000, publications involving protein biomarker discovery constituted 87% of the total number of research articles with DNA comprising 6% and RNA 7%. Since 2000 the proportion of protein biomarker articles has fallen to 40%, and DNA and RNA studies increased to 32% and 28%, respectively. Clearly research focus, perhaps driven by technological innovation, has shifted from proteins to nucleic acids. We optimistically hypothesise that, following thorough validation, a clinically useful detection test for bladder cancer based on a panel of DNA or RNA markers could become reality within 5-10 years.

Tumoral markers in bladder cancer (Review)

Bladder tumors are frequently diagnosed urologic malignant diseases with an extremely high recurrence rate compared to other neoplastic tumors. Urothelial bladder carcinomas are mostly identified in their incipient form, as non-muscle invasive, but despite that, a third of them develop into aggressive recurrent disease. The diagnosis of bladder carcinoma at this moment is established using cytology and cystoscopy and is a great challenge for clinicians due to the lack of sensitivity. Urinary biomarkers could improve and enhance the diagnosis and screening techniques and determine a more accurate recurrence rate. However, bladder cancer is a heterogeneous disease and the existence of a single marker test with reduced cost is unlikely; thus, until then, the use of a panel of markers to obtain valuable information is inevitable even though suboptimal for use. To improve this deadlock, new biomarker panels should be identified and prepared to equalize the cost-efficiency balance. The present paper is a literature review concerning the most commonly used tumor markers in urinary bladder cancer as well as the most commonly encountered genetic modifications in such patients.

Research Progress of Urine Biomarkers in the Diagnosis, Treatment, and Prognosis of Bladder Cancer

Bladder cancer (BC) is one of the most common tumor with high incidence. Relative to other cancers, BC has a high rate of recurrence, which results in increased mortality. As a result, early diagnosis and life-long monitoring are clinically significant for improving the long-term survival rate of BC patients. At present, the main methods of BC detection are cystoscopy and biopsy; however, these procedures can be invasive and expensive. This can lead to patient refusal and reluctance for monitoring. There are several BC biomarkers that have been approved by the FDA, but their sensitivity, specificity, and diagnostic accuracy are not ideal. More research is needed to identify suitable biomarkers that can be used for early detection, evaluation, and observation. There has been heavy research in the proteomics and genomics of BC and many potential biomarkers have been found. Although the advent of metabonomics came late, with the recent development of advanced analytical technology and bioinformatics, metabonomics has become a widely used diagnostic tool in clinical and biomedical research. It should be emphasized that despite progress in new biomarkers for BC diagnosis, there remains challenges and limitations in metabonomics research that affects its translation into clinical practice. In this chapter, the latest literature on BC biomarkers was reviewed.

Noninvasive Urine-Based Tests to Diagnose or Detect Recurrence of Bladder Cancer

Liquid biopsies are increasingly used for the diagnosis and follow-up of cancer patients. Urine is a body fluid that can be used to detect cancers and others diseases. It is noninvasive and easy to collect. To detect Bladder Cancer (BC), cytology is the first assay used. It is an effective way to detect high grade BC but has a high rate of equivocal results, especially for low grade BC. Furthermore, cystoscopy is used to confirm cytology results and to determine cancer status. Cystoscopy is also effective but highly invasive, and not well accepted by patients, especially for BC follow-up. In this review we survey the numerous assays recently developed in order to diagnose BC at an early stage, and to facilitate the follow-up of patients. We discuss their effectiveness, ease of use, and applications. Finally, we discuss assays that, in the future, could improve the diagnosis and management of BC patients.

Can new immunoassay techniques improve bladder cancer diagnostics With protein biomarkers?

The search for new diagnostic tests for cancer or ways to improve existing tests is primarily driven by the desire to identify the disease as early as possible. In this report, we summarize the current knowledge of the most promising diagnostic protein bladder cancer (BC) markers reported over the last decade. Unfortunately, analysis of published data suggests that a reliable, highly sensitive biomarker test-system based on ELISA for detecting BC has not yet been developed. The use of more sensitive assays to detect ultra-low concentrations of biomarkers not available for ELISA, could be very beneficial. Based on the literature and pilot experimental data, we conclude that a highly sensitive immunoassay using microarrays and magnetic labels, could be an effective and cheap technique suitable for the detection of diagnostically relevant BC biomarkers.

Biomarkers for Precision Urothelial Carcinoma Diagnosis: Current Approaches and the Application of Single-Cell Technologies

Simple Summary

Urothelial carcinoma (UC) is the most frequently diagnosed cancer of the urinary tract and is ranked the sixth most diagnosed cancer in men worldwide. About 70–75% of newly diagnosed UCs are non-invasive or low grade. Different tests such as urine cytology and cystoscopy are used to detect UC. If abnormal tissue is found during cystoscopy, then a biopsy will be performed. Cytology has low sensitivity for low-grade cancer while cystoscopy is invasive and costly. Detecting UC early improves the chances of treatment success. Therefore, many researchers have painstakingly identified urine biological markers for non-invasive UC diagnosis. In this review, we summarize some of the latest and most promising biological markers (including FDA-approved and investigational markers). We also discuss some new technologies that can aid research efforts in biological marker discovery for early UC detection.

Abstract

Urothelial carcinoma (UC) is the most frequent malignancy of the urinary system and is ranked the sixth most diagnosed cancer in men worldwide. Around 70–75% of newly diagnosed UC manifests as the non-muscle invasive bladder cancer (NMIBC) subtype, which can be treated by a transurethral resection of the tumor. However, patients require life-long monitoring due to its high rate of recurrence. The current gold standard for UC diagnosis, prognosis, and disease surveillance relies on a combination of cytology and cystoscopy, which is invasive, costly, and associated with comorbidities. Hence, there is considerable interest in the development of highly specific and sensitive urinary biomarkers for the non-invasive early detection of UC. In this review, we assess the performance of current diagnostic assays for UC and highlight some of the most promising biomarkers investigated to date. We also highlight some of the recent advances in single-cell technologies that may offer a paradigm shift in the field of UC biomarker discovery and precision diagnostics.

Proteomic profiling of bladder cancer for precision medicine in the clinical setting: A review for the busy urologist

At present, proteomic methods have successfully identified potential biomarkers of urological malignancies, such as prostate cancer (PC), bladder cancer (BC), and renal cell carcinoma (RCC), reflecting different numbers of key cellular processes, including extracellular environment modification, invasion and metastasis, chemotaxis, differentiation, metabolite transport, and apoptosis. The potential application of proteomics in the detection of clinical markers of urological malignancies can help improve patient assessment through early cancer detection, prognosis, and treatment response prediction. A variety of proteomic studies have already been carried out to find prognostic BC biomarkers, and a large number of potential biomarkers have been reported. It is worth noting that proteomics research has not been applied to the study of predictive markers; this may be due to the incompatibility between the number of measured variables and the available sample size, which has become particularly evident in the study of therapeutic response. On the contrary, prognostic correlation is more common, which is also reflected in existing research. We are now entering an era of clinical proteomics. Driven by proteomic-based workflows, computing tools, and the applicability of cross-correlation of proteomic data, it is now feasible to use proteomic analysis to support personalized medicine. In this paper, we will summarize the current emerging technologies for advanced discovery, targeted proteomics, and proteomic applications in BC, particularly in discovery of human-based biomarkers.

Establishment and Characterization of an Empirical Biomarker SS/PV-ROC Plot Using Results of the UBC® Rapid Test in Bladder Cancer

BACKGROUND

This investigation included both a study of potential non-invasive diagnostic approaches for the bladder cancer biomarker UBC^® Rapid Test and a study including comparative methods about sensitivity-specificity characteristic (SS-ROC) and predictive receiver operating characteristic (PV-ROC) curves that used bladder cancer as a useful example.

METHODS

The study included 289 urine samples from patients with tumors of the urinary bladder, patients with non-evidence of disease (NED) and healthy controls. The UBC^® Rapid Test is a qualitative point of care assay. Using a photometric reader, quantitative data can also be obtained. Data for pairs of sensitivity/specificity as well as positive/negative predictive values were created by variation of threshold values for the whole patient cohort, as well as for the tumor-free control group. Based on these data, sensitivity-specificity and predictive value threshold distribution curves were constructed and transformed into SS-ROC and PV-ROC curves, which were included in a single SS/PV-ROC plot.

RESULTS

The curves revealed TPP-asymmetric improper curves which cross the diagonal from above. Evaluation of the PV-ROC curve showed that two or more distinct positive predictive values (PPV) can correspond to the same value of a negative predictive value (NPV) and vice versa, indicating a complexity in PV-ROC curves which did not exist in SS-ROC curves. In contrast to the SS-ROC curve, the PV-ROC curve had neither an area under the curve (AUC) nor a range from 0% to 100%. Sensitivity of the qualitative assay was 58.5% and specificity 88.2%, PPV was 75.6% and NPV 77.3%, at a threshold value of approximately 12.5 µg/L.

CONCLUSIONS

The SS/PV-ROC plot is a new diagnostic approach which can be used for direct judgement of gain and loss of predictive values, sensitivity and specificity according to varied threshold value changes, enabling characterization, comparison and evaluation of qualitative and quantitative bioassays.

Urinary Biomarkers in Bladder Cancer: Where Do We Stand and Potential Role of Extracellular Vesicles

Extracellular vesicles (EVs) are small membrane vesicles released by all cells and involved in intercellular communication. Importantly, EVs cargo includes nucleic acids, lipids, and proteins constantly transferred between different cell types, contributing to autocrine and paracrine signaling. In recent years, they have been shown to play vital roles, not only in normal biological functions, but also in pathological conditions, such as cancer. In the multistep process of cancer progression, EVs act at different levels, from stimulation of neoplastic transformation, proliferation, promotion of angiogenesis, migration, invasion, and formation of metastatic niches in distant organs, to immune escape and therapy resistance. Moreover, as products of their parental cells, reflecting their genetic signatures and phenotypes, EVs hold great promise as diagnostic and prognostic biomarkers. Importantly, their potential to overcome the current limitations or the present diagnostic procedures has created interest in bladder cancer (BCa). Indeed, cystoscopy is an invasive and costly technique, whereas cytology has poor sensitivity for early staged and low-grade disease. Several urine-based biomarkers for BCa were found to overcome these limitations. Here, we review their potential advantages and downfalls. In addition, recent literature on the potential of EVs to improve BCa management was reviewed and discussed.

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.

UBC® Rapid Test-A Urinary Point-of-Care (POC) Assay for Diagnosis of Bladder Cancer with a focus on Non-Muscle Invasive High-Grade Tumors: Results of a Multicenter-Study

Objectives: UBC^®Rapid Test measures soluble fragments of cytokeratins 8 and 18 in urine. We present results of a multicenter study using an updated version of UBC^®Rapid Test in bladder cancer patients, patients with urinary bladder cancer positive history, and healthy controls. Material and Methods: In total 530 urine samples have been included in this study. Clinical urine samples were used from 242 patients with tumors of the urinary bladder (134 non-muscle-invasive low-grade tumors (NMI-LG), 48 non-muscle-invasive high-grade tumors (NMI-HG), and 60 muscle-invasive high-grade tumors (MI-HG)), 62 patients with non-evidence of disease (NED), and 226 healthy controls. Urine samples were analyzed by the UBC^® Rapid point-of-care (POC) assay and evaluated by Concile Omega 100 POC Reader. All statistical analyses have been performed using R version 3.2.3. Results: Elevated levels of UBC^® Rapid Test in urine are higher in patients with bladder cancer in comparison to the control group (p < 0.001). The sensitivity for the whole bladder cancer cohort was 53.3% (positive predictive value (PPV) 90.2%, negative predictive value (NPV) 65.2%) and was 38.8% (PPV 78.8%, NPV 72.1%) for non-muscle-invasive low-grade bladder cancer; 75.0% (PPV 72.0%, NPV 94.7%) for non-muscle-invasive high-grade bladder cancer and 68.3% (PPV 74.6%, NPV 91.8%) for muscle-invasive high-grade bladder cancer. The specificity for the statistical calculations was 93.8%. The cut-off value (10 µg/L) was evaluated for the whole patient cohort. The area under the curve of the quantitative UBC^® Rapid Test using the optimal threshold obtained by receiver operating characteristics (ROC) analysis was 0.774. Elevated values of UBC^®Rapid Test in urine are higher in patients with high-grade bladder cancer in comparison to low-grade tumors and the healthy control group. Conclusions: UBC^®Rapid Test has potential to be a clinically valuable urinary protein biomarker for detection of high-grade bladder cancer patients and could be added in the management of NMI-HG tumors. UBC^®Rapid results generated in both study centers in the present multicenter study are very similar and reproducible. Furthermore UBC^®Rapid Test is standardized and calibrated and thus independent of used batch of test as well as study site.

Urinary Markers in Bladder Cancer: An Update

Bladder cancer (BC) is ones of the most common cancer worldwide. It is classified in muscle invasive (MIBC) and muscle non-invasive (NMIBC) BC. NMIBCs frequently recur and progress to MIBCs with a reduced survival rate and frequent distant metastasis. BC detection require unpleasant and expensive cystoscopy and biopsy, which are often accompanied by several adverse effects. Thus, there is an urgent need to develop novel diagnostic methods for initial detection and surveillance in both MIBCs and NMIBCs. Multiple urine-based tests approved by FDA for BC detection and surveillance are commercially available. However, at present, sensitivity, specificity and diagnostic accuracy of these urine-based assays are still suboptimal and, in the attend to improve them, novel molecular markers as well as multiple-assays must to be translated in clinic. Now there are growing evidence toward the use of minimally invasive “liquid biopsy” to identify biomarkers in urologic malignancy. DNA- and RNA-based markers in body fluids such as blood and urine are promising potential markers in diagnostic, prognostic, predictive and monitoring urological malignancies. Thus, circulating cell-free DNA, DNA methylation and mutations, circulating tumor cells, miRNA, IncRNA and mRNAs, cell-free proteins and peptides, and exosomes have been assessed in urine specimens. However, proteomic and genomic data must to be validated in well-designed multicenter clinical studies, before to be employed in clinic oncology.

Diagnostic accuracy of the UBC® Rapid Test for bladder cancer: A meta-analysis

Bladder cancer is one of the most common cancer types globally. The UBC^® Rapid Test is a potential novel diagnostic method for bladder cancer, but studies into its accuracy have produced inconsistent results. Thus, the present meta-analysis was conducted in order to determine the overall accuracy of the UBC^® Rapid Test in detecting bladder cancer. A comprehensive literature search was conducted using MEDLINE, Embase, Cochrane Library, Web of Science, Chinese WanFang and the China National Knowledge Infrastructure databases for relevant studies. Quality assessment of diagnostic accuracy studies 2 was used to assess the quality of each included study. The diagnostic accuracy of the UBC^® Rapid Test was evaluated by pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and the area under the curve (AUC). In addition, Deeks' funnel plot was used to evaluate potential publication bias. Eight studies were included in the quantitative meta-analysis. The results were as follows: Sensitivity 0.59 [95% confidence interval (CI), 0.55–0.62], specificity 0.76 (95% CI, 0.72–0.80), PLR 2.55 (95% CI, 1.75–3.70), NLR 0.56 (95% CI, 0.46–0.67), DOR 4.88 (95% CI, 2.82–8.45) and AUC 0.70 (95% CI, 0.67–0.74). According to the present results, the UBC^® rapid test is highly accurate in the diagnosis of bladder cancer, however, further studies with better-designed and larger samples are required in order to support the results of the present study.

[Urinary marker-old wine in new bottles?]

Some urine-based molecular markers can be used effectively in certain clinical situations, but so far none of them have made it into the daily routine. For this purpose, clinical validation in large multicentre prospective studies with defined endpoints is lacking, whereby the cost effectiveness should also be a criterion of the evaluation. This also applies to the many promising "research parameters", which were usually only examined in small groups of patients. The uniform standardization of molecular biological methods is the first step that makes a comparison possible. Current impediments to conducting such studies include elaborate analytics and their still high costs. In summary, the development that has occurred-from the uroscopy to the information that a drop of urine is able to provide today-gives an optimistic outlook on the future: the old idea (of comprehensive urine diagnostics) in new bottles (with new analysis methods?) maybe yet be realized.

Novel urinary biomarkers for the detection of bladder cancer: A systematic review

BACKGROUND

Urinary biomarkers for the diagnosis of bladder cancer represents an area of considerable research which has been tested in both patients presenting with haematuria and non-muscle invasive bladder cancer patients requiring surveillance cystoscopy. In this systematic review, we identify and appraise the diagnostic sensitive and specificity of reported novel biomarkers of different 'omic' class and highlight promising biomarkers investigated to date.

METHODS

A MEDLINE/Pubmed systematic search was performed between January 2013 and July 2017 using the following keywords: (bladder cancer OR transitional cell carcinoma OR urothelial cell carcinoma) AND (detection OR diagnosis) AND urine AND (biomarker OR assay). All studies had a minimum of 20 patients in both bladder cancer and control arms and reported sensitivity and/or specificity and/or receiver operating characteristics (ROC) curve. QUADAS-2 tool was used to assess risk of bias and applicability of studies. The search protocol was registered in the PROSPERO database (CRD42016049918).

RESULTS

Systematic search yielded 115 reports were included for analysis. In single target biomarkers had a sensitivity of 2-94%, specificity of 46-100%, positive predictive value (PPV) of 47-100% and negative predictive value (NPV) of 21-94%. Multi-target biomarkers achieved a sensitivity of 24-100%, specificity of 48-100%, PPV of 42-95% and NPV of 32-100%. 50 studies achieved a sensitivity and specificity of ≥80%. Protein (n = 59) and transcriptomic (n = 21) biomarkers represents the most studied biomarkers. Multi-target biomarker panels had a better diagnostic accuracy compared to single biomarker targets. Urinary cytology with urinary biomarkers improved the diagnostic ability of the biomarker. The sensitivity and specificity of biomarkers were higher for primary diagnosis compared to patients in the surveillance setting. Most studies were case control studies and did not have a predefined threshold to determine a positive test result indicating a possible risk of bias.

CONCLUSION

This comprehensive systematic review provides an update on urinary biomarkers of different 'omic' class and highlights promising biomarkers. Few biomarkers achieve a high sensitivity and negative predictive value. Such biomarkers will require external validation in a prospective observational setting before adoption in clinical practice.

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.

Evaluation of a New Survivin ELISA and UBC® Rapid for the Detection of Bladder Cancer in Urine

Urine-based biomarkers for non-invasive diagnosis of bladder cancer are urgently needed. No single marker with sufficient sensitivity and specificity has been described so far. Thus, a combination of markers appears to be a promising approach. The aim of this case-control study was to evaluate the performance of an in-house developed enzyme-linked immunosorbent assay (ELISA) for survivin, the UBC^®Rapid test, and the combination of both assays. A total of 290 patients were recruited. Due to prior bladder cancer, 46 patients were excluded. Urine samples were available from 111 patients with bladder cancer and 133 clinical controls without urologic diseases. Antibodies generated from recombinant survivin were utilized to develop a sandwich ELISA. The ELISA and the UBC^®Rapid test were applied to all urine samples. Receiver operating characteristic (ROC) analysis was used to evaluate marker performance. The survivin ELISA exhibited a sensitivity of 35% with a specificity of 98%. The UBC^®Rapid test showed a sensitivity of 56% and a specificity of 96%. Combination of both assays increased the sensitivity to 66% with a specificity of 95%. For high-grade tumors, the combination showed a sensitivity of 82% and a specificity of 95%. The new survivin ELISA and the UBC^®Rapid test are both able to detect bladder cancer, especially high-grade tumors. However, the performance of each individual marker is moderate and efforts to improve the survivin assay should be pursued. A combination of both assays confirmed the benefit of using marker panels. The results need further testing in a prospective study and with a high-risk population.