Qualitative and quantitative assessment of urinary cytokeratin 8 and 18 fragments compared with voided urine cytology in diagnosis of bladder carcinoma

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.

Urinary Biomarkers In Bladder Cancer

Bladder cancer has a very high frequency of recurrence and therefore requires close clinical surveillance throughout its life, with cystoscopies and serial cytological examinations. These tests are both invasive and expensive, with considerable interpersonal and inter-institutional variability. Moreover, cytological examination used for the diagnosis of low-grade tumors has a low sensitivity; thus, there is an increasing focus on the research for new, accurate, urinary markers. Herein, the biological basis, methodologies, and diagnostic performance of biomarkers are discussed.

Urinary biomarkers in bladder cancer: where do we stand?

PURPOSE OF REVIEW

To provide a current comprehensive review of the available urinary biomarkers for the detection and surveillance of bladder cancer.

RECENT FINDINGS

The limitations of urine cytology and invasive nature of cystoscopic evaluation have led to a growing search for an ideal, cost-effective biomarker with acceptable sensitivity and specificity. Current FDA approved biomarkers such as UroVysion fluorescent in situ hybridization, Immunocyt, and nuclear matrix protein 22 do not have the specificity, and thus positive predictive value to warrant their cost as a routine adjunct or replacement for cystoscopy. Several promising commercially available assays such as Cxbladder, Assure MDx, and Xpert BC may perform better than cytology in select populations. Novel genomic, epigenetic, inflammatory, and metabolomic-based assays are being analyzed as potential urinary biomarkers.

SUMMARY

Urinary biomarkers with high sensitivity and specificity are an unmet need in bladder cancer. Several new assays may meet these criteria and future research may justify use in clinical practice.

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.

Liquid Biopsy Biomarkers in Bladder Cancer: A Current Need for Patient Diagnosis and Monitoring

Bladder Cancer (BC) represents a clinical and social challenge due to its high incidence and recurrence rates, as well as the limited advances in effective disease management. Currently, a combination of cytology and cystoscopy is the routinely used methodology for diagnosis, prognosis and disease surveillance. However, both the poor sensitivity of cytology tests as well as the high invasiveness and big variation in tumour stage and grade interpretation using cystoscopy, emphasizes the urgent need for improvements in BC clinical guidance. Liquid biopsy represents a new non-invasive approach that has been extensively studied over the last decade and holds great promise. Even though its clinical use is still compromised, multiple studies have recently focused on the potential application of biomarkers in liquid biopsies for BC, including circulating tumour cells and DNA, RNAs, proteins and peptides, metabolites and extracellular vesicles. In this review, we summarize the present knowledge on the different types of biomarkers, their potential use in liquid biopsy and clinical applications in BC.

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 Protein Markers for the Detection and Prognostication of Urothelial Carcinoma

Bladder cancer diagnosis and surveillance is mainly based on cystoscopy and urine cytology. However, both methods have significant limitations; urine cytology has a low sensitivity for low-grade tumors, while cystoscopy is uncomfortable for the patients. Therefore, in the last decade urine analysis was the subject of intensive research resulting in the identification of many potential biomarkers for the detection, surveillance, or prognostic stratification of bladder cancer. Current trends move toward the development of multiparametric models to improve the diagnostic accuracy compared with single molecular markers. Recent technical advances for high-throughput and more sensitive measurements have led to the development of multiplex assays showing potential for more efficient tools toward future clinical application. In this review, we focus on the findings of urinary protein research in the context of detection and prognostication of bladder cancer. Furthermore, we provide an up-to-date overview on the recommendations for the quality evaluation of published studies as well as for the conduction of future urinary biomarker studies.

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.

Urinary UBC Rapid and NMP22 Test for Bladder Cancer Surveillance in Comparison to Urinary Cytology: Results from a Prospective Single-Center Study

Background: Non-muscle invasive bladder cancer (NMIBC) is associated with high rates of recurrence, resulting in frequent follow-up cystoscopies. We evaluated the use of two point-of-care tests - the nuclear matrix protein 22 (NMP22) and urinary bladder cancer antigen (UBC) Rapid - compared to routine follow-up in patients with a previous history of NMIBC. Methods: 31 patients with cystoscopy-verified active bladder cancer, and 44 follow-up patients without disease as confirmed by cystoscopy were prospectively enrolled. All urine samples were analyzed by voided urine and bladder washing cytology, NMP22 and UBC rapid test (qualitatively and quantitatively). The best cutoff (highest Youden index; ≥6.7 ng/ml) for the quantitative UBC was determined by receiver operating characteristic curves. Results: Voided urine and barbotage cytology resulted in a sensitivity of 25.8% and 32.3%, and a specificity of 100% and 100%, while the NMP22 showed a sensitivity and specificity of 12.9% and 100%, respectively. The qualitative and quantitative UBC Rapid revealed a sensitivity of 61.3% and 64.5%, with a specificity of 77.3% and 81.8%. Barbotage cytology and qualitative UBC test proved to be the best dual combination with the highest overall sensitivity (77.4%). In contrast to barbotage cytology alone, sensitivity increased from 21.4% to 50% for detecting low-grade tumors, and from 43.8% to 100% for high-grade cancers, but reducing specificity from 100% to 77.3%. Conclusion: Compared to urinary cytology, UBC tests alone as well as UBC tests in combination with bladder washing cytology revealed higher sensitivities in detecting low- and high-grade tumors, but at the expense of a lower specificity. Thus, currently cystoscopy cannot be replaced by any of the evaluated methods.

A Systematic Review of the Diagnostic and Prognostic Value of Urinary Protein Biomarkers in Urothelial Bladder Cancer

For over 80 years, cystoscopy has remained the gold-standard for detecting tumours of the urinary bladder. Since bladder tumours have a tendency to recur and progress, many patients are subjected to repeated cystoscopies during long-term surveillance, with the procedure being both unpleasant for the patient and expensive for healthcare providers. The identification and validation of bladder tumour specific molecular markers in urine could enable tumour detection and reduce reliance on cystoscopy, and numerous classes of biomarkers have been studied. Proteins represent the most intensively studied class of biomolecule in this setting. As an aid to researchers searching for better urinary biomarkers, we report a comprehensive systematic review of the literature and a searchable database of proteins that have been investigated to date. Our objective was to classify these proteins as: 1) those with robustly characterised sensitivity and specificity for bladder cancer detection; 2) those that show potential but further investigation is required; 3) those unlikely to warrant further investigation; and 4) those investigated as prognostic markers. This work should help to prioritise certain biomarkers for rigorous validation, whilst preventing wasted effort on proteins that have shown no association whatsoever with the disease, or only modest biomarker performance despite large-scale efforts at validation.

Biomarkers for non-muscle invasive bladder cancer: Current tests and future promise

The search continues for optimal markers that can be utilized to improve bladder cancer detection and to predict disease recurrence. Although no single marker has yet replaced the need to perform cystoscopy and urine cytology, many tests have been evaluated and are being developed. In the future, these promising markers may be incorporated into standard practice to address the challenge of screening in addition to long-term surveillance of patients who have or are at risk for developing bladder cancer.

Evaluation of a new quantitative point-of-care test platform for urine-based detection of bladder cancer

OBJECTIVE

Several commercial point-of-care (POC) tests are available for urine-based detection of bladder cancer (BC). However, these tests are restricted to dichotomized results (positive or negative), which limits their diagnostic value. Quantitative protein-based tests offer improved risk stratification but require complex methods restricted to specialized centers. Recently, the first quantitative POC system based on the detection of cytokeratin fragments became available. The aim of the study was to evaluate the diagnostic accuracy of this quantitative POC test.

PATIENTS AND METHODS

A total of 198 patients having symptoms suspicious for BC were included. All patients received urethrocystoscopy and upper-tract imaging. Urine samples were analyzed by the urine BC antigen (UBC) rapid POC system and evaluated both visually and quantitatively using the concile Omega 100 POC reader. For visual evaluation, different thresholds of band intensity for considering a test positive were applied. Moreover, the UBC enzyme-linked immunosorbent assay (ELISA), urine cytology, and the nuclear matrix protein 22 BladderChek were performed. Sensitivities and specifities were calculated by contingency analyses. Optimal cutoffs of quantitative tests were determined by receiver operating characteristic curves.

RESULTS

A total of 61 patients (30.8%) were diagnosed with BC. Visual evaluation of the UBC revealed sensitivities of 38.1% to 71.4% with corresponding specificities of 54.1% to 89.1%, dependent on the threshold of band intensity applied. The quantitative UBC rapid showed a sensitivity of 60.7% and a specificity of 70.1% at optimal cutoff (area under the curve = 0.68). A constant increase of both the probability of BC and high-risk BC with increasing UBC rapid values was observed. UBC concentrations determined by the reader significantly correlated with the UBC ELISA (P<0.001). The UBC ELISA, the nuclear matrix protein22 BladderChek and cytology showed sensitivities of 48.3%, 16.4%, and 51.7% with specificities of 71.3%, 95.3%, and 78.1%, respectively.

CONCLUSION

The UBC rapid in combination with a quantitative POC-reader system for the first time enables quantitative determination of a BC marker under POC conditions. Diagnostic accuracy is at least equivalent to elaborate ELISA-based measurement. The quantitative use of the UBC rapid test facilitates risk prediction compared with conventional nonquantitative dichotomized POC testing.

[Urine marker systems for diagnosis of urothelial cancer]

Cystoscopy and urinary cytology are standard tools in the diagnostics of urothelial cancer of the urinary bladder; however, cystoscopy is invasive and urinary cytology lacks accuracy for the diagnosis of low grade tumors. More recently several alternative urinary test systems were developed with the aim to make the diagnostics of urothelial tumors more reliable; however, in general all protein-based point of care test systems have a high rate of false positive test results, especially in patients with benign disorders. Fluorescence in situ hybridization, which is highly sensitive and specific, may be a reasonable supplement to the diagnostic spectrum in patients after instillation therapy or bladder replacement. Additionally, there are several new test systems which still need to be tested in large clinical studies with respect to diagnostic accuracy.

A proteomic study of potential VEGF-C-associated proteins in bladder cancer T24 cells

Background

Overexpression of vascular endothelial growth factor-C (VEGF-C) has been found to play an important role in malignant progression of various cancer cells, in addition to lymphangiogenesis. However, the mechanisms involved are still largely unknown. Our early research has confirmed that the expression of VEGF-C in bladder cancer was markedly higher than that in normal bladder tissues. VEGF-C can also obviously promote proliferation and invasion of bladder cancer T24 cells. In the present work, we attempted to use proteomic analysis to screen out potential VEGF-C-associated proteins involved in malignant progression of the bladder cancer T24 cells.

Material/Methods

Lentivirus vector-based RNA interference (RNAi) was employed to diminish VEGF-C expression of bladder cancer T24 cells. Then we performed comparative proteome analysis to explore differentially expressed proteins in T24 cells with and without VEGF-C siRNA, by two-dimensional difference gel electrophoresis (2D-DIGE).

Results

Twenty-three proteins were identified. Some proteins (matrix metalloproteinase-9, Keratin 8, Serpin B5, Annexin A8) with significant differences were further confirmed by Western blotting.

Conclusions

The 23 potential VEGF-C-associated proteins identified in our study provide us with further insights into the mechanism of VEGF-C promoting malignant progression of bladder cancer cells.

Proteomic assays for the detection of urothelial cancer

Bladder cancer is one of the most expensive cancers from diagnosis to death of the patient due to life-long surveillance involving upper tract imaging, urinary cytology, and cystoscopy. Cytology has been historically used in conjunction with cystoscopy to help detect disease that may be missed by routine cystoscopy (e.g., carcinoma in situ and upper tract disease). Urine cytology is highly cytopathologist dependent and has reasonable sensitivity for detecting high grade disease. However, its sensitivity drops precipitously with regard to well-differentiated low grade cancers. Intensive investigations have been undertaken using proteomics to find an alternative to cystoscopy and cytology. Urine proteomic markers currently evaluated critically in the literature include bladder tumor antigen, nuclear matrix protein 22, BLCA-4, hyaluronic acid, hyaluronidase, cytokeratin 8, cytokeratin 18, cytokeratin 19, tissue polypeptide antigen, and tissue polypeptide-specific antigen. Markers used as alternatives to cystoscopy must be accurate with high sensitivity and specificity, cost effective for life-long surveillance, and minimally invasive to minimize the burden to the patient. To date, no proteomic marker has been developed that can replace cystoscopy for the detection of bladder cancer. However, several urinary markers appear to have higher sensitivity albeit lower specificity than cytology and can be used to supplement cystoscopy. Some of those markers are herein described in this chapter. By defining and characterizing the current state of the art in protein based markers, we are poised to evaluate and benchmark newly discovered protein biomarkers that will be isolated through new proteomics based investigations of urine.

Molecular markers for detection, surveillance and prognostication of bladder cancer

Many markers for the detection of bladder cancers have been tested and almost all urinary markers reported are better than cytology with regard to sensitivity, but they score lower in specificity. Currently molecular and genetic changes play an important role in the discovery of new molecular markers for detection, prognostication and surveillance. The purpose of this review is to highlight the most important urinary molecular biomarker developments that have been studied and reported recently. In the current review we have summarized the most recent and relevant published reports on molecular urinary markers. The results of this review show that the first generation of urinary markers did not add much to urinary cytology. The current generation of markers is better, but additional clinical trials are needed. Our knowledge of molecular pathways in bladder cancer is growing and new methods of marker development emerge, but the perfect marker is still to be found. Currently, there are not clinically usable molecular markers that can guide us in diagnosis or surveillance, nor guide us in lowering the frequency of urethrocystoscopy in bladder cancer.

Bladder tumor markers: from hematuria to molecular diagnostics--where do we stand?

Bladder cancer is a common malignancy in the USA. Currently, the detection of initial tumors and recurrent disease is based on evaluation of voided urinary specimens, often followed by cystoscopy. With the high rate of recurrence, cystoscopies are regularly repeated with the aim of halting progression of the disease. For patients, this process is fraught with anxiety, pain and high cost. As a result, intense work is being done in the field of bladder tumor markers with the goal of identifying bladder cancer earlier, both in the initial diagnosis and in recurrences of known tumor. The possibility of identifying a marker that could noninvasively differentiate benign and malignant causes of hematuria, and identify recurrences prior to their pathologic progression is the objective of this area of research. Currently, a large number of tumor markers exist, each scrutinized in both the laboratory and in clinical trials. Here we present many of the most widely used and tested markers. Background details are provided as to the mechanism of detection of malignant cells, the results of recent trials and future directions of study. Some novel modalities for tumor detection are also presented. The next few years will no doubt bring newer markers and lead to the elimination of others. Studies continue to refine the role of these markers in clinical practice, but their ultimate efficacy will need to be borne out in large-scale clinical trials in a multitude of settings.

Evaluation of urine tumor-associated trypsin inhibitor, CYFRA 21-1, and urinary bladder cancer antigen for detection of high-grade bladder carcinoma

OBJECTIVES

To assess the value of urine tumor-associated trypsin inhibitor (TATI), CYFRA 21-1, which measures cytokeratin 19 fragment, and urinary bladder carcinoma antigen (UBC) for the detection of high-grade bladder carcinoma.

METHODS

A total of 160 individuals were enrolled in the present study. Of these, 80 were patients with proven primary high-grade urothelial bladder cancer (group 1), 40 were healthy volunteers (group 2), and 40 had history of benign urologic disease (group 3). All were evaluated with respect to urinary TATI, CYFRA 21-1, and UBC levels. All these markers were evaluated using commercial kits. Cytology was also performed.

RESULTS

The TATI measurements were significant greater in group 1 compared with groups 2 and 3. The cutoff point used for TATI, CYFRA 21-1, and UBC was 22, 2.8, and 12 microg/L, respectively. The overall sensitivity was 85.7% for TATI, 61.9% for CYFRA 21-1, 50% for UBC, and 42.8% for cytology. TATI was significantly more sensitive in Stage Ta (80%) than was CYFRA 21-1 (32%), UBC (12%), and cytology (20%). TATI was also more sensitive compared with other tumor markers for Stage T1 but not for Stage T2 or T3.

CONCLUSIONS

The results of our study have shown that TATI is a promising urinary tumor marker for high-grade urothelial bladder cancer. It is more sensitive than CYFRA 21-1, UBC, and cytology for Stage Ta and T1 bladder cancer.

Urinary markers in bladder cancer

OBJECTIVES

Many markers for the detection of bladder cancers have been tested. Almost all urinary markers reported are better than cytology with regard to sensitivity, but they score lower in specificity. The purpose of this review is to highlight the most important urinary biomarkers studied and reported recently.

METHODS

Literature on bladder cancer markers has been reviewed regularly in the last few years. In the current review we have tried to summarise the most recent literature of urinary markers.

RESULTS

The results of this review show that the first-generation urinary markers did not add much to urinary cytology. The current generation of markers is promising but larger clinical trails are needed. The future of marker development is bright with new techniques emerging, but the perfect marker is still to be found.

CONCLUSION

Currently, no single marker can yet guide us in surveillance and lower the frequency of urethrocystoscopy.

Comparative Diagnostic Value of Urine Cytology, UBC-ELISA, and Fluorescence In Situ Hybridization for Detection of Transitional Cell Carcinoma of Urinary Bladder in Routine Clinical Practice

OBJECTIVES

Fluorescence in situ hybridization (FISH) has been reported to have much better sensitivity for the detection of bladder transitional cell carcinoma (TCC) than urine cytology. We comparatively tested cytology, FISH, and the cytokeratin-detection test of urinary bladder cancer (UBC) in routine clinical practice.

METHODS

In a prospective study, FISH, the urinary bladder cancer test (UBC-enzyme-linked immunosorbent assay [ELISA]), and cytology were used in 166 patients. Of the 166 patients, 62 had primary TCC (group 1), 71 had undergone transurethral resection of primary TCC before routine secondary transurethral resection (group 2), and 33 control had not undergone TCC (group 3). All patients with false-positive test results were followed up for a mean follow-up time of 22 months.

RESULTS

The overall sensitivity of FISH, UBC-ELISA, and cytology was 53.2% (95% confidence interval 40% to 66%), 40.3% (95% confidence interval 28% to 53%), and 71.0% (95% confidence interval 59% to 83%), respectively (P <0.05). For grade 3 TCC, both FISH and cytology reached a sensitivity of 93.3%. In the 104 patients without TCC, the specificity of FISH, UBC-ELISA, and cytology was 74.0%, 75.0%, and 83.7%, respectively. During follow-up, 33.3% of patients with a false-positive FISH result developed recurrence, as did 23.1% with false-positive UBC results and 29.4% with false-positive cytology findings (P >0.05). Receiver operating characteristic analysis showed an area under the curve for FISH, UBC, and cytology of 0.636, 0.577, and 0.773, respectively. Only cytology and FISH were significantly predictive of a TCC finding on histologic examination (P <0.001 and P = 0.003, respectively).

CONCLUSIONS

In routine clinical practice, conventional cytology in experienced hands can be superior to FISH. False-positive results with all three test systems used warrant a high suspicion of subclinical precursor lesions of TCC recurrence.

Molecular Markers of Urothelial Cancer and Their Use in the Monitoring of Superficial Urothelial Cancer

Multiple molecular markers have been described for use in bladder cancer patients. Some of these have been studied more extensively than others, and it is difficult for the clinician to maintain a perspective over the myriad findings that have been made. We have reviewed a selection of markers used for surveillance with an emphasis on clinical utility. The best studied markers and those with the most promising preliminary results were selected. Only studies that included surveillance for recurrence in patients with a history of bladder cancer were considered. Each marker is briefly described and its performance in monitoring bladder cancer patients is summarized. Several promising markers are available, although only four have obtained US Food and Drug Administration approval. The clinical applications that have been studied include replacement or reduction in the number of cystoscopies performed in the surveillance of bladder cancer patients, substitution for or complementary use with urinary cytology in the same setting, predicting disease recurrence and progression, and predicting and monitoring treatment response. None of the markers have been proved sensitive and specific enough to replace cystoscopy. Others, such as nuclear matrix protein 22 (NMP22) and UroVysion, appear to have some utility when used to complement or replace cytology. The other applications have not been adequately studied for any given marker. While multiple molecular markers exist for bladder cancer, their full clinical utility will not be realized until more multicenter prospective trials are conducted to verify their efficacy and safety in the monitoring of patients with superficial bladder cancer.

Evaluation of Survivin Reverse Transcriptase-Polymerase Chain Reaction for Noninvasive Detection of Bladder Cancer

PURPOSE

Survivin, a member of the inhibitor of apoptosis gene family, is expressed in most common cancers. We investigated the expression pattern of survivin in the tumors of patients with bladder cancer and assessed the diagnostic potential of RT-PCR detection of survivin mRNA in urine.

MATERIALS AND METHODS

RT-PCR was used to analyze mRNA expression of survivin in 161 cases of bladder cancer, including TCC in 97, SCC in 53 and adenocarcinoma in 11, and their matched nontumor tissues. Urine specimens (50 ml) were collected from 84 patients in whom bladder cancer was documented by transurethral resection or biopsy, 41 with nonbladder cancer urological diseases and 42 healthy volunteers. Total RNA was extracted from urine sediments and RT-PCR was performed for survivin.

RESULTS

Survivin expression was detected in all bladder cancer tissues. In contrast, survivin was not detectable in normal urothelium specimens. Urinary survivin was detected in urine samples from 51 of 53 patients with TCC, 22 of 25 with SCC and 6 of 6 with adenocarcinoma. Overall sensitivity was 94%. Survivin mRNA was not detected in any healthy volunteers. Positive results were obtained in 2 patients with renal cell carcinoma, 1 with hematuria and 1 with a contracted bladder but in none with other urological diseases. Overall specificity was 95%.

CONCLUSIONS

Survivin mRNA detection in urine sediment using RT-PCR shows high sensitivity and specificity for bladder cancer. It may prove useful for the routine screening and monitoring of patients.

Rapid diagnosis and follow up of bladder cancer patients using urinary high molecular weight cytokeratins

We have developed an office-based dot-EIA for the detection of a urinary high molecular weight cytokeratin (CK). Immunohistochemical staining and western blot based on CK1K10 monoclonal antibody were used to identify the CK. Urine of 192 patients with different types, grades, and stages of bladder tumor and 72 controls were evaluated using dot-EIA. An intense and diffuse cytoplasmic reaction was shown in bladder squamous cell carcinoma. The target epitope was identified in urine at 65, 56, and 40-kDa. The CK purified from urine showed single polypeptide at 65-kDa using SDS-PAGE and single peak at 7.4 min using capillary zone electrophoresis. The dot-EIA detected the CK with high sensitivity (97%) and specificity (94%). The CK was not detected in urine of bladder cancer patients showing response to radiotherapy. The sensitive and specific office-based detection of urinary cytokeratin would be helpful in rapid diagnosis and follow up of bladder carcinoma.

Cytokeratin-20 immunocytology in voided urine exhibits greater sensitivity and reliability than standard cytology in the diagnosis of transitional cell carcinoma of the bladder

OBJECTIVES

To investigate whether immunocytochemical detection of cytokeratin (CK)-20 could serve as a reliable diagnostic marker for transitional cell carcinoma (TCC) of the bladder.

METHODS

A total of 232 patients were enrolled in the study. Group 1 consisted of 144 patients with histologically confirmed TCC (62 at diagnosis and 82 in follow-up), and group 2 consisted of 88 subjects, including healthy volunteers and individuals with "non-TCC" conditions. Spontaneously voided urine specimens were obtained from each patient and submitted to immunocytologic and standard cytologic examination.

RESULTS

CK-20 immunocytology yielded an overall sensitivity of 65.3%, significantly greater than the sensitivity of urine cytology (54.2%, P = 0.013). A more detailed analysis revealed a sensitivity advantage for the former technique in the detection of primary (61.3% versus 51.6%, P = 0.046), recurrent (68.3% versus 56.1%, P = 0.027), Stage pT1 (81.8% versus 59.1%, P = 0.006), grade 2 (76.2% versus 61.9%, P = 0.031), and grade 3 (82.1% versus 67.9%, P = 0.039) tumors. Moreover, CK-20 immunocytochemistry demonstrated greater overall specificity than cytology (90.9% versus 86.4%, respectively), a difference stemming from the subgroup of lithiasis patients (100% versus 66.7%, P = 0.024). In terms of reliability, the positive and negative predictive values of the immunoassay were greater than those calculated for cytology (92.2% versus 86.7% and 61.5% versus 53.5%, respectively).

CONCLUSIONS

CK-20 immunocytology is more sensitive than standard cytology in the detection of TCC, particularly of Stage pT1, grade 2, and grade 3 tumors. In view of its high overall specificity and predictive accuracy, it is conceivable that the proposed immunoassay may progressively replace conventional cytologic screening in the diagnosis of bladder cancer.