Nuclear matrix protein-22: a prospective evaluation in a population at risk for bladder cancer. Results from the UroScreen study

Off the fog to find the optimal choice: Research advances in biomarkers for early diagnosis and recurrence monitoring of bladder cancer

Bladder cancer (BC) has high morbidity and mortality rates owing to challenges in clinical diagnosis and treatment. Advanced BC is prone to recurrence after surgery, necessitating early diagnosis and recurrence monitoring to improve the prognosis of patients. Traditional detection methods for BC include cystoscopy, cytology, and imaging; however, these methods have drawbacks such as invasiveness, lack of sensitivity, and high costs. Existing reviews on BC focus on treatment and management and lack a comprehensive assessment of biomarkers. Our article reviews various biomarkers for the early diagnosis and recurrence monitoring of BC and outlines the existing challenges associated with their application and possible solutions. Furthermore, this study highlights the potential application of urine biomarkers as a non-invasive, inexpensive adjunctive test for screening high-risk populations or evaluating patients with suspected BC symptoms, thereby alleviating the discomfort and financial burden associated with cystoscopy and improving patient survival.

An ensemble approach of urine sediment image analysis and NMP22 test for detection of bladder cancer cells

Background

Bladder cancer is the eighth most common cancer and the second most common urological cancer in Korean males. Current diagnostic tools for bladder cancer include cystoscopy (an upper tract study), urine cytology, and nuclear matrix protein 22 (NMP22) test. In this study, we evaluated the detection rate of atypical/malignant urothelial cells in urinary sediment images when flagged for positive NMP22 test.

Methods

NMP22 was measured by NMP22 BladderChek Test (Abbott Laboratories) and urine chemical and sediment analysis were performed by fully automated cobas 6500 urine analyzer (Roche Diagnostics). Specimens that met the manual microscopic examination (MME) criteria were then subjected to an on‐screen review of images. We subsequently reviewed sediment images and examined under the microscopy for the flagged cases.

Results

Of the 1217 patients, 345 (28.3%) had positive NMP22 results, whereas 872 (71.7%) had negative results. Out of the positive results, 154 (12.7%) were positive and 191 (15.7%) weakly positive for NMP22. Screened review of flagged specimens (ie, positive NMP22 result) with sediment imaging analysis revealed that suspicious urothelial carcinoma cells were detected in only two cases (0.8%). In the NMP22 negative flagged cases, the suspicious neoplastic cells were not found.

Conclusions

Our findings suggest that the NMP22 test should be added to the flagging criteria for MME to improve diagnostic accuracy. The combination of urine sediment imaging analysis and NMP22 test can significantly assist technicians in the review of specimens.

Urinary TERT promoter mutations are detectable up to 10 years prior to clinical diagnosis of bladder cancer: Evidence from the Golestan Cohort Study

BACKGROUND

Detecting pre-clinical bladder cancer (BC) using urinary biomarkers may provide a valuable opportunity for screening and management. Telomerase reverse transcriptase (TERT) promoter mutations detectable in urine have emerged as promising BC biomarkers.

METHODS

We performed a nested case-control study within the population-based prospective Golestan Cohort Study (50,045 participants, followed up to 14 years) and assessed TERT promoter mutations in baseline urine samples from 38 asymptomatic individuals who subsequently developed primary BC and 152 matched controls using a Next-Generation Sequencing-based single-plex assay (UroMuTERT) and droplet digital PCR assays.

FINDINGS

Results were obtained for 30 cases and 101 controls. TERT promoter mutations were detected in 14 pre-clinical cases (sensitivity 46·67%) and none of the controls (specificity 100·00%). At an estimated BC cumulative incidence of 0·09% in the cohort, the positive and negative predictive values were 100·00% and 99·95% respectively. The mutant allelic fractions decreased with the time interval from urine collection until BC diagnosis (p = 0·033) but the mutations were detectable up to 10 years prior to clinical diagnosis.

INTERPRETATION

Our results provide the first evidence from a population-based prospective cohort study of the potential of urinary TERT promoter mutations as promising non-invasive biomarkers for early detection of BC. Further studies should validate this finding and assess their clinical utility in other longitudinal cohorts.

FUNDING

French Cancer League, World Cancer Research Fund International, Cancer Research UK, Tehran University of Medical Sciences, the International Agency for Research on Cancer, and the U.S. National Cancer Institute.

Systematic verification of bladder cancer-associated tissue protein biomarker candidates in clinical urine specimens

Bladder cancer biomarkers currently approved by the Food and Drug Administration are insufficiently reliable for use in non-invasive clinical diagnosis. Verification/validation of numerous biomarker candidates for BC detection is a crucial bottleneck for novel biomarker development. A multiplexed liquid chromatography multiple-reaction-monitoring mass spectrometry assay of 122 proteins, including 118 up-regulated tissue proteins, two known bladder cancer biomarkers and two housekeeping gene products, was successfully established for protein quantification in clinical urine specimens. Quantification of 122 proteins was performed on a large cohort of urine specimens representing a variety of conditions, including 142 hernia, 126 bladder cancer, 67 hematuria, and 59 urinary tract infection samples. ANXA3 (annexin A3) and HSPE1 (heat shock protein family E member 1), which showed the highest detection frequency in bladder cancer samples, were selected for further validation. Western blotting showed that urinary ANXA3 and HSPE1 protein levels were higher in bladder cancer samples than in hernia samples, and enzyme-linked immunosorbent assays confirmed a higher urinary concentration of HSPE1 in bladder cancer than in hernia, hematuria and urinary tract infection. Immunohistochemical analyses showed significantly elevated levels of HSPE1 in tumor cells compared with non-cancerous bladder epithelial cells, suggesting that HSPE1 could be a useful tumor tissue marker for the specific detection of bladder cancer. Collectively, our findings provide valuable information for future validation of potential biomarkers for bladder cancer diagnosis.

Circulating tumor cells in genitourinary tumors

Management of advanced urogenital malignancies has profoundly changed in recent years due to the development of novel targeted drugs that have significantly improved patient's clinical outcomes. This process has been made possible mainly thanks to better knowledge of tumor genetic alterations and molecular altered pathways. Despite these remarkable results, several issues such as early detection of the disease as well as the research into early markers of recurrence or disease progression still remain an open challenge for clinical research. The detection of circulating tumor cells and circulating DNA appears an attractive option since it is a minimally invasive approach potentially able to allow clinicians an accurate diagnosis and maybe lead to more customized treatment strategies. This review focuses on the current techniques adopted for the detection and isolation of circulating tumor cells in genitourinary tumors highlighting their present and possible future application in clinical practice.

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.

The Diagnostic Value of Nuclear Matrix Proteins in Bladder Cancer in the Aspect of Environmental Risk from Carcinogens

BACKGROUND

The interaction of environmental factors with genetic susceptibility and detoxification level seems to be an important causative factor in bladder cancer (BC). The aim of this study was to look for a BC marker panel which reflects the environmental risk. The nuclear matrix protein 22 (NMP22), bladder cancer-4 (BLCA-4), and total level proteins NMP22 and BLCA-4 (NMBL) in BC patients with genetic predisposition NAT2 (classified as slow acetylators, SA), DNA damage (8-OHdG), and detoxification by isoenzyme GSTπ activity were measured.

MATERIALS AND METHODS

The urine and blood from 91 BC patients and controls were examined, also according to tumor stage (T) and grade (G). The participants completed a questionnaire in order to evaluate environmental risk.

RESULTS

Most patients (75.3%) were previous or actual smokers. The levels of 8-OHdG, NMP22, BLCA-4, NMBL, and GSTπ were significantly higher in BC (p ≤ 0.001). The majority of patients (59.3%) were slow acetylators (SA). The highest BLCA-4/8-OHdG correlation was observed in total BC and SA smokers.

CONCLUSIONS

The total pool of nuclear matrix proteins in the urine (NMBL) has a higher diagnostic value in bladder cancer than single proteins. The particular value of BLCA-4 and GSTπ in the aspect of environmental risk was noted.

Noninvasive Diagnosis of High-Grade Urothelial Carcinoma in Urine by Raman Spectral Imaging

The current gold standard for the diagnosis of bladder cancer is cystoscopy, which is invasive and painful for patients. Therefore, noninvasive urine cytology is usually used in the clinic as an adjunct to cystoscopy; however, it suffers from low sensitivity. Here, a novel noninvasive, label-free approach with high sensitivity for use with urine is presented. Coherent anti-Stokes Raman scattering imaging of urine sediments was used in the first step for fast preselection of urothelial cells, where high-grade urothelial cancer cells are characterized by a large nucleus-to-cytoplasm ratio. In the second step, Raman spectral imaging of urothelial cells was performed. A supervised classifier was implemented to automatically differentiate normal and cancerous urothelial cells with 100% accuracy. In addition, the Raman spectra not only indicated the morphological changes that are identified by cytology with hematoxylin and eosin staining but also provided molecular resolution through the use of specific marker bands. The respective Raman marker bands directly show a decrease in the level of glycogen and an increase in the levels of fatty acids in cancer cells as compared to controls. These results pave the way for "spectral" cytology of urine using Raman microspectroscopy.

Influence of hematuria and infection on diagnostic accuracy of urinary LASP1: a new biomarker for bladder carcinoma

AIM

To further promote the clinical use of urinary LASP1 as biomarker for urothelial carcinoma of the bladder regarding limitations and alternative testing systems.

PATIENTS & METHODS

Urine stabilization, alternative measurement systems and limitations by erythrocyte contamination and infection were investigated in 246 patients.

RESULTS

Thimerosal allowed sufficient stabilization. Fluorescence-activated cell sorting analysis was not influenced by presence of erythrocytes or leukocytes and reliably urothelial carcinoma of the bladder but cell counts in specimen were low. Cut-off values of <25 leukocytes and <200 erythrocytes/µl resulted in sensitivity, specificity, positive and negative predictive values of 0.59, 0.80, 0.80 and 0.59, respectively.

CONCLUSION

Hematuria up to 200 erythrocytes/µl but not presence of leukocytes may be tolerated for this promising marker.

The value of the NMP22 test for superficial bladder cancer diagnosis and follow-up

OBJECTIVE

In this study, we investigated the efficacy of nuclear matrix protein 22 (NMP22) in the diagnosis and surveillance of bladder cancer.

MATERIAL AND METHODS

Patients with hematuria or who applied for cystoscopic control of proven bladder cancer were prospectively enrolled in this study. Routine cytologic examination and NMP22 test were performed on the voided urine sample obtained before the cystoscopy. The patients who had been diagnosed with bladder cancer were categorized according to stage, grade, number, size of the tumor and risk of the disease. Then the diagnostic performance of the NMP22 and the cytology test, alone or in combination, were evaluated separately using ROC curves in the diagnosis and surveillance groups.

RESULTS

A total of 87 patients (87/136) were investigated because of hematuria. The sensitivity, specificity, positive and, negative predictive values, and positive likelihood ratio (LR+) of the NMP22 test were 70, 80, 68, 81, and 3.42%, respectively. While, the sensitivity, specificity, positive and, negative predictive values, and positive likelihood ratio (LR+) of the cytology examination were 27, 96, 82, 68, and 7.36%, respectively. There were 49 patients in the bladder cancer group. The sensitivity, specificity, positive, and negative predictive values and positive likelihood ratio (LR+) of the NMP22 test in these patients were 33, 76, 31, 78 and 1.37%, respectively. The sensitivity, specificity, positive and, negative predictive values, and positive likelihood ratio (LR+) of the cytology examination were 25%, 97%, 75%, 80% and 9.25, respectively.

CONCLUSION

NMP22 test can be used as an adjunctive tool for the detection of bladder cancer, but its diagnostic performance is limited in surveillance when used alone or in combination with a cytology examination.

Imidazolium salts as small-molecule urinary bladder exfoliants in a murine model

We present a novel family of small-molecule urinary bladder exfoliants that are expected to be of great value in preclinical studies of urologic conditions and have improved potential for translation compared with prior agents. There is broad urologic interest in the therapeutic potential of such exfoliating agents. The primary agent used in preclinical models, the cationic peptide protamine sulfate (PS), has limited translational potential due to concerns including systemic adverse reactions and bladder tissue injury. Intravesical application of a safe, systemically nontoxic exfoliant would have potential utility in the eradication of Escherichia coli and other uropathogens that reside in the bladder epithelium following cystitis, as well as in chronic bladder pain and bladder cancer. Here, we introduce a family of imidazolium salts with potent and focused exfoliating activity on the bladder epithelium. Synthesis and purification were straightforward and scalable, and the compounds exhibited prolonged stability in lyophilized form. Most members of the compound family were cytotoxic to cultured uroepithelial cells, with >10-fold differences in potency across the series. Upon topical (intravesical) administration of selected compounds to the murine bladder, complete epithelial exfoliation was achieved with physiologically relevant imidazolium concentrations and brief contact times. The exfoliative activity of these compounds was markedly improved in comparison to PS, as assessed by microscopy, immunofluorescence, and immunoblotting for uroplakins. Bladder uroepithelium regenerated within days to yield a histologically normal appearance, and no toxicity was observed. Finally, the chemical scaffold offers an opportunity for inclusion of antimicrobials or conjugation with chemotherapeutic or other moieties.

Developing proteomic biomarkers for bladder cancer: towards clinical application

Clinical use of proteomic biomarkers has the potential to substantially improve the outcomes of patients with bladder cancer. An unmet clinical need evidently exists for noninvasive biomarkers, which might enable improvements in both the diagnosis and prognosis of patients with bladder cancer, as well as improved monitoring of patients for the presence of recurrence. Urine is considered the optimal noninvasive source of proteomic biomarkers in patients with bladder cancer. Currently, a number of single-protein biomarkers have been detected in urine and tissue using a variety of proteomic techniques, each having specific conceptual considerations and technical implications. Promising preclinical data are available for several of these proteins; however, the combination of single urinary proteins into multimarker panels might better encompass the molecular heterogeneity of bladder cancer within this patient population, and prove more effective in clinical use.

Epidemiologic design and analysis for proteomic studies: a primer on -omic technologies

Proteome analysis is increasingly being used in investigations elucidating the molecular basis of disease, identifying diagnostic and prognostic markers, and ultimately improving patient care. We appraised the current status of proteomic investigations using human samples, including the state of the art in proteomic technologies, from sample preparation to data evaluation approaches, as well as key epidemiologic, statistical, and translational issues. We systematically reviewed the most highly cited clinical proteomic studies published between January 2009 and March 2014 that included a minimum of 100 samples, as well as strategies that have been successfully implemented to enhance the translational relevance of proteomic investigations. Limited comparability between studies and lack of specification of biomarker context of use are frequently observed. Nevertheless, there are initial examples of successful biomarker discovery in cross-sectional studies followed by validation in high-risk longitudinal cohorts. Translational potential is currently hindered, as limitations in proteomic investigations are not accounted for. Interdisciplinary communication between proteomics experts, basic researchers, epidemiologists, and clinicians, an orchestrated assimilation of required resources, and a more systematic translational outlook for accumulation of evidence may augment the public health impact of proteomic investigations.

APE1/Ref-1 as a Serological Biomarker for the Detection of Bladder Cancer

Purpose

Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) is a multifunctional protein that shows elevated expression in a number of cancers. We attempted to determine whether serum APE1/Ref-1 is elevated in patients with bladder cancer.

Materials and Methods

Serum APE1/Ref-1 levels were determined using enzyme-linked immunosorbent assay in serum from patients with bladder cancer who had not received chemotherapy or radiotherapy (n=51) and non-tumor controls (n=55). The area under the receiver operating characteristic area under the curve was applied to determine the correlation between clinical factors and the serum levels of APE1/Ref-1.

Results

Serum levels of APE1/Ref-1 in bladder cancer patients were significantly elevated compared to those of the control group (3.548±0.333 ng/100 μL [n=51] for bladder cancer vs. 1.547±0.319 ng/100 μL [n=55] for the control group), with a sensitivity and specificity of 93% and 59%, respectively. Serum APE1/Ref-1 levels are associated with tumor stage, grade, muscle invasion, and recurrence.

Conclusion

Serum APE1/Ref-1 might be useful as a potential serologic biomarker for bladder cancer.

The promise of novel molecular markers in bladder cancer

Bladder cancer is the fourth most common malignancy in the US and is associated with the highest cost per patient. A high likelihood of recurrence, mandating stringent surveillance protocols, has made the development of urinary markers a focus of intense pursuit with the hope of decreasing the burden this disease places on patients and the healthcare system. To date, routine use of markers is not recommended for screening or diagnosis. Interests include the development of a single urinary marker that can be used in place of or as an adjunct to current screening and surveillance techniques, as well identifying a molecular signature for an individual’s disease that can help predict progression, prognosis, and potential therapeutic response. Markers have shown potential value in improving diagnostic accuracy when used as an adjunct to current modalities, risk-stratification of patients that could aid the clinician in determining aggressiveness of surveillance, and allowing for a decrease in invasive surveillance procedures. This review discusses the current understanding of emerging biomarkers, including miRNAs, gene signatures and detection of circulating tumor cells in the blood, and their potential clinical value in bladder cancer diagnosis, as prognostic indicators, and surveillance tools, as well as limitations to their incorporation into medical practice.

Chromosomal alterations in exfoliated urothelial cells from bladder cancer cases and healthy men: a prospective screening study

Background

Chromosomal instability in exfoliated urothelial cells has been associated with the development of bladder cancer. Here, we analyzed the accumulation of copy number variations (CNVs) using fluorescence in situ hybridization in cancer cases and explored factors associated with the detection of CNVs in tumor-free men.

Methods

The prospective UroScreen study was designed to investigate the performance of UroVysion™ and other tumor tests for the early detection of bladder cancer in chemical workers from 2003–2010. We analyzed a database compiling CNVs of chromosomes 3, 7, and 17 and at 9p21 that were detected in 191,434 exfoliated urothelial cells from 1,595 men. We assessed the accumulation of CNVs in 1,400 cells isolated from serial samples that were collected from 18 cancer cases up to the time of diagnosis. A generalized estimating equation model was applied to evaluate the influence of age, smoking, and urine status on CNVs in cells from tumor-free men.

Results

Tetrasomy of chromosomes 3, 7 and 17, and DNA loss at 9p21 were the most frequently observed forms of CNV. In bladder cancer cases, we observed an accumulation of CNVs that started approximately three years before diagnosis. During the year prior to diagnosis, cells from men with high-grade bladder cancer accumulated more CNVs than those obtained from cases with low-grade cancer (CNV < 2: 7.5% vs. 1.1%, CNV > 2: 16-17% vs. 9-11%). About 1% of cells from tumor-free men showed polysomy of chromosomes 3, 7, or 17 or DNA loss at 9p21. Men aged ≥50 years had 1.3-fold more cells with CNVs than younger men; however, we observed no further age-related accumulation of CNVs in tumor-free men. Significantly more cells with CNVs were detected in samples with low creatinine concentrations.

Conclusions

We found an accumulation of CNVs during the development of bladder cancer starting three years before diagnosis, with more altered cells identified in high-grade tumors. Also, a small fraction of cells with CNVs were exfoliated into urine of tumor-free men, mainly exhibiting tetraploidy or DNA loss at 9p21. Whether these cells are preferentially cleared from the urothelium or are artifacts needs further exploration.

Prospective evaluation of fluorescence-guided cystoscopy to detect bladder cancer in a high-risk population: results from the UroScreen-Study

Objective

To prospectively evaluate the role of fluorescence-guided cystoscopy in a high-risk bladder cancer population undergoing screening based on a multi-marker panel of urine-tests (UroScreen-study).

Patients and methods

UroScreen was conducted as a validation study for tumor markers within the frame of a health surveillance program of workers with occupational exposure to aromatic amines. Voluntary annual screens were done in 1,609 men. Cytology, quantitative NMP22® assay, and UroVysion (FISH) were applied to 7091 urine samples. Subjects with at least one positive urine-based tumor marker and/or persisting microscopic hematuria were offered fluorescence-guided (PDD) instead of white light cystoscopy. In case of suspicious findings histopathological evaluation by transurethral biopsy was performed. Data were statistically summarized and compared to tumors found by the standard algorithm of the screening study.

Results

Twenty-two subjects with a mean age of 58 years (39–72) underwent PDD cystoscopy. Of those 3 had positive NMP22 tests, 14 positive FISH tests and 9 suspicious cytologies. Two had persisting microscopic hematuria only. PDD cystoscopy revealed enhanced unifocal fluorescence in 14. All had subsequent transurethral biopsy or resection. In total, 1 urothelial carcinoma (pTaG1, low grade) was diagnosed. In the other participants urothelial cancer of the bladder was ruled out. Chronic cystitis was revealed in 8 of 14 biopsies. No higher detection rate was found using PDD than with the standard algorithm of the UroScreen study in which 17 tumors were detected by white light cystoscopy.

Conclusion

The use of PDD does not lead to a higher cancer detection rate in a high-risk screening population. Larger sample sizes may be needed to ultimately asses the value of PDD for bladder cancer screening.

Considerations on the use of urine markers in the management of patients with low-/intermediate-risk non-muscle invasive bladder cancer

OBJECTIVES

Many molecular assays for bladder cancer diagnosis and surveillance have been developed over the past several decades. However, none of these markers have been routinely implemented into clinical decision making. Beyond their potential for screening high-risk populations, urine markers likely have the greatest potential in the follow-up of patients with non-muscle invasive bladder cancer (NMIBC).

METHODS

Here, we discuss the current options and limitations of the use of urine markers for patient surveillance, focusing on patients with low-/intermediate-risk NMIBC.

RESULTS

As these patients have a very low risk of tumor progression, the primary goal of surveillance is detection of recurrent disease. Although urine cytology seems to be limited to detection of few patients who would develop high-grade tumors, we conclude that the use of markers with high sensitivity for low-grade disease for patient follow-up has the potential to decrease the frequency of urethrocystoscopy without compromising patient prognosis. Because a single marker may not have sufficient sensitivity for detection of low-grade tumors, different scenarios, e.g., multitesting and reflex or sequential approaches, are discussed.

CONCLUSIONS

There is consensus that currently available markers have the potential to support clinical decision making in follow-up of patients with low-/intermediate-risk NMIBC. In light of our analysis, further additional randomized controlled studies to effectively assess the clinical usefulness of modern urine markers are required.

Biomarker research with prospective study designs for the early detection of cancer

This article describes the principles of marker research with prospective studies along with examples for diagnostic tumor markers. A plethora of biomarkers have been claimed as useful for the early detection of cancer. However, disappointingly few biomarkers were approved for the detection of unrecognized disease, and even approved markers may lack a sound validation phase. Prospective studies aimed at the early detection of cancer are costly and long-lasting and therefore the bottleneck in marker research. They enroll a large number of clinically asymptomatic subjects and follow-up on incident cases. As invasive procedures cannot be applied to collect tissue samples from the target organ, biomarkers can only be determined in easily accessible body fluids. Marker levels increase during cancer development, with samples collected closer to the occurrence of symptoms or a clinical diagnosis being more informative than earlier samples. Only prospective designs allow the serial collection of pre-diagnostic samples. Their storage in a biobank upgrades cohort studies to serve for both, marker discovery and validation. Population-based cohort studies, which may collect a wealth of data, are commonly conducted with just one baseline investigation lacking serial samples. However, they can provide valuable information about factors that influence the marker level. Screening programs can be employed to archive serial samples but require significant efforts to collect samples and auxiliary data for marker research. Randomized controlled trials have the highest level of evidence in assessing a biomarker's benefit against usual care and present the most stringent design for the validation of promising markers as well as for the discovery of new markers. In summary, all kinds of prospective studies can benefit from a biobank as they can serve as a platform for biomarker research. This article is part of a Special Issue entitled: Biomarkers: A Proteomic Challenge.

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.

Screening for bladder cancer with urinary tumor markers in chemical workers with exposure to aromatic amines

PURPOSE

To validate urinary markers for the early detection of bladder cancer (BC) in chemical workers.

METHODS

UroScreen was conducted as a validation study for tumor markers within the frame of a health surveillance program of the German Social Accident Insurance for active or retired workers with former exposure to aromatic amines. From 2003 to 2010, 1,609 men took part in voluntary annual screens. Cytology, the quantitative NMP22(®) assay, and UroVysion™ were applied to 7,091 urine samples.

RESULTS

Fifteen out of 21 tumors were detected following test positivity. The UroVysion/NMP22 panel detected 14 out of 21 tumors versus 8 tumors with cytology alone (sensitivity 66.7 vs. 44.4 %, specificity 94.5 vs. 98.5 %). The sensitivity of the panel increased to 85.7 % in samples collected ≤12 months before diagnosis and when papillomas were excluded, compared to 58.3 % with cytology. About 3 % of NMP22 tests were false-positive. UroVysion results overlapped with cytology due to the preselection of atypical cells. NMP22 was less and UroVysion more frequently positive in diluted urine samples. Leukocytes confounded NMP22 but not UroVysion. The low incidence of BC in this study population yielded low positive predictive values of the markers and high costs per tumor detected with screening.

CONCLUSIONS

UroVysion in combination with NMP22 detected more cases than cytology alone, at the expense of a lower specificity. High costs per detected case resulted from a lower BC incidence than in the past when levels of occupational exposure to aromatic amines were higher. Currently, it cannot be recommended to apply these markers for screening in asymptomatic workers. The increase in sensitivity is not balanced by the high costs of UroVysion and the false-positive tests of NMP22.

Urinary biomarkers of bladder cancer: an update and future perspectives

Bladder cancer is one of the most prevalent cancers worldwide. Early detection of bladder tumors is critical for improved patient outcomes. The standard method for detection and surveillance of bladder tumors is cystoscopy with urinary cytology. Limitations of cystoscopy and urinary cytology have brought to light the need for more robust diagnostic assays. Ideally, such assays would be applicable to noninvasively obtained, voided urine, and be designed not only for diagnosis, but also for monitoring disease recurrence and response to therapy. Consequently, the development of a noninvasive urine-based assay would be of tremendous benefit to both patients and healthcare systems. This article reports some of the more prominent urine-based biomarkers reported in the literature. In addition, some new technologies that have been used to identify novel urinary biomarkers are highlighted.

Bladder cancer detection and monitoring: assessment of urine- and blood-based marker tests

Bladder cancer is one of the most prevalent cancers worldwide, but the treatment and management of this disease can be very successful if the disease is detected early. The development of molecular assays that could diagnose bladder cancer accurately, and at an early stage, would be a significant advance. Ideally, such molecular assays would be applicable to non-invasively obtained body fluids, and be designed not only for diagnosis but also for monitoring disease recurrence and response to treatment. In this article, we assess the performance of current diagnostic assays for bladder cancer and discuss some of the emerging biomarkers that could be developed to augment current bladder cancer detection strategies.

Urinary markers for bladder cancer

Bladder cancer has the fifth highest incidence of all malignancies in the United States, with a propensity to recur, requiring lifelong surveillance after diagnosis. Urinary markers of disease have been of extreme interest in this field in an effort to simplify surveillance schedules and improve early detection of tumors. Many markers have been described, but most remain investigational. However, some markers have undergone clinical trials and are approved for clinical use. In this review, urinary markers and their application for screening and surveillance of bladder cancer are discussed.

Chromosomal instability and bladder cancer: the UroVysion(TM) test in the UroScreen study

What's known on the subject? and what does the study add?: UroVysion™ is a multicolour fluorescence in situ hybridisation assay that detects DNA gain at chromosomes 3, 7 and 17 and loss at the 9p21 locus in exfoliated urothelial cells. This cell-based test is time-consuming and costly compared with voided urine cytology or other molecular markers for the early detection of bladder cancer. We determined copy number changes at chromosomes 3, 7 and 17 and at the 9p21 locus with UroVysion in a prospective screening study among chemical workers. Strong correlations between DNA gains yield a similar performance in detecting bladder cancer with just one of the probes for chromosomes 3, 7 or 17 instead of all, supporting the development of a simpler and cheaper assay.

OBJECTIVE

To explore changes at chromosomes 3, 7, 17 and 9p21 in order to assess associations with bladder cancer for possible improvements of the UroVysion™ assay regarding screening.

SUBJECTS AND METHODS

In all, 1609 men took part in the prospective study UroScreen. Annual screening for bladder cancer was offered to male chemical workers with former exposure to aromatic amines as a voluntary surveillance programme between 2003 and 2010. In all, 191 434 cells in 6517 UroVysion tests were analysed for copy number variations (CNV) at chromosome 3, 7, 17 (gains) and 9p21 (deletions) in 1595 men. We assessed CNVs at single or multiple loci using polysomy indices (PIs, called multiple PI and PI 3, PI 7 and PI 17). We calculated Spearman's rank correlation coefficients (rs ) between these PIs and receiver operating characteristic (ROC) curves with areas under the curves (AUCs). We applied Cox regression to estimate hazard ratios (HRs) to assess the risk of developing bladder cancer.

RESULTS

Nine out of 21 bladder tumours detected in 20 participants ('cases') had a positive UroVysion test, including seven high-grade carcinomas and seven overlapping results with a positive cytology. Four cases with negative test results did not attend screening annually. No case was found because of a complete loss of 9p21 in at least 12 cells. There were strong correlations between pairwise combinations of gains at chromosome 3, 7 or 17, ranging between rs = 0.98 and rs = 0.99 in cases and between rs = 0.84 and rs = 0.88 in non-cases (P < 0.001). Associations were less pronounced with CNVs at 9p21 among cases and were lacking in non-cases. Estimates of the relative risk of DNA gain for developing a bladder tumour assessed with PIs (threshold 10% of cells) were 47.7 (95% confidence interval [CI] 18.3-124.1) for the multiple PI, 44.5 (95%CI 16.5-119.9) for PI 3, 34.7 (95%CI 13.1-92.1) for PI 7 and 52.4 (95%CI 20.7-132.6) for PI 17, as well as 7.9 (95%CI 3.0-20.6) for a complete loss of 9p21 (threshold 2.5% of cells), respectively. ROC analyses showed similar AUCs for multiple PI compared with PIs of single chromosomes 3, 7 and 17 (all AUCs between 0.79 and 0.80) and a lower AUC for a homozygous loss of 9p21 (AUC 0.72).

CONCLUSIONS

The UroVysion assay showed a reasonable performance in detecting bladder cancer in the present study population and shared positive test results with cytology, which is much cheaper. A simpler, faster and cheaper version of the UroVysion assay might rely on the very strong correlations between gains at chromosomes 3, 7 and 17, resulting in a similar performance in detecting bladder cancer with single-probe PIs compared with the full set of these probes. Loss of 9p21 was less predictive for developing bladder cancer in UroScreen.

Combined application of cytology and molecular urine markers to improve the detection of urothelial carcinoma

BACKGROUND

The sensitivity of cytology for the detection of urothelial carcinoma (UC) is limited. Newer methods such as fluorescence in situ hybridization (FISH), immunocytology (uCyt+), and protein markers have been developed to improve urine-based detection of UC. As only little is known regarding the combined application of these markers, we investigated whether combinations of 4 of the most broadly available tests (cytology, FISH, uCyt+, and nuclear matrix protein 22 [NMP22-ELISA]) may improve their diagnostic performance.

METHODS

The study was comprised of 808 patients who were suspected of having UC. All patients underwent urethrocystoscopy and upper urinary tract imaging and, in the case of positive findings, transurethral resection/biopsy. FISH, uCyt+, cytology, and NMP22-ELISA were performed in all patients.

RESULTS

UC was diagnosed in 115 patients (14.2%). Cytology and FISH were found to be the single tests with the best overall performance (area under the curve [AUC], 0.78/0.79). Combinations of 2, 3, and 4 markers were found to increase the AUC to various extents compared with the use of single markers. Combining cytology and FISH improved the sensitivity and performance (AUC, 0.83) compared with the single tests and identified 12 tumors that were not detected by cytology alone. The percentage of WHO grade 3/carcinoma in situ tumors not detected by cytology was reduced by 62.5% when FISH was performed in cytology-negative patients. The addition of uCyt+ as a third test further improved performance (AUC, 0.86), whereas the addition of NMP22-ELISA was not found to have any additional influence on the performance of the test combination.

CONCLUSIONS

The results of the current study support the combined use of urine markers and may form the basis of further studies investigating whether risk stratification based on urine marker combinations may individualize diagnostic algorithms and the surveillance of patients suspected of having UC.

High-risk non-muscle-invasive bladder cancer: update for a better identification and treatment

PURPOSE

Despite standard treatment with transurethral resection (TUR) and adjuvant bacillus Calmette-Guérin (BCG), many high-risk bladder cancers (HRBCs) recur and some progress. Based on a review of the literature, we aimed to establish the optimal current approach for the early diagnosis and management of HRBC.

METHODS

A MEDLINE® search was conducted to identify the published literature relating to early identification and treatment for non-muscle-invasive bladder cancer. Particular attention was paid to factors such as quality of TUR, importance of second TUR, substaging, and CIS. In addition, studies on urinary markers, photodynamic diagnosis, predictive clinical and molecular factors for recurrence and progression after BCG, and best management practice were analysed.

RESULTS AND CONCLUSIONS

Good quality of TUR and the implementation of photodynamic diagnosis in selected cases provide a more accurate diagnosis and reduce the risk of residual tumour in HRBC. Although insufficient evidence is available to warrant the use of new urinary molecular markers in isolation, their use in conjunction with cytology and cystoscopy may improve early diagnosis and follow-up. BCG plus maintenance for at least 1 year remains the standard adjuvant treatment for HRBC. Moreover, there is enough evidence to consider the implementation of new specific risk tables for patients treated with BCG. In HRBC patients with poor prognostic factors after TUR, early cystectomy should be considered.

Influencing factors on the NMP-22 urine assay: an experimental model

BACKGROUND

The commercial NMP-22 urine assays for bladder cancer (BCa) detect nuclear mitotic apparatus protein 1 (NUMA1) using monoclonal antibodies. It remains unclear whether these assays are monitoring a tumor antigen or some other phenomenon associated with the disease state. In this study, we investigated the influence of urinary cellular and protein concentration, and hematuria on the performance of the NMP-22 tests in an experimental model.

METHODS

Pooled urine from healthy subjects were spiked with varying concentrations of benign (UROtsa) cells, cancer cells (RT4, T24, KU-7 and UM-UC-14), whole blood or serum, prior to analysis with both NMP22® Bladder Cancer ELISA test and the NMP22® BladderChek® point-of-care test.

RESULTS

Urines from control subjects were negative for NMP-22. The addition of whole blood at 50ul/10 ml, but not serum, resulted in a false-positive result. Furthermore, the addition of a high concentration of benign urothelial cells (10(6)) or the cell lysate from these cells (306 μg protein) resulted in a false-positive result. High concentrations of pooled-cancer cells (10(6)) or cell lysate (30.6 μg and above) resulted in a positive NMP-22 assay. Concordance between the NMP-22 ELISA assay and the NMP-22 point of care assay was >90%.

CONCLUSIONS

Rather than detecting a specific tumor antigen, urinary NMP-22 assays may be measuring the cellularity or amount of cell turnover that may be introduced into the urine by a variety of conditions, including surface shedding from bladder tumors. The absence of significant urinary cellularity in some cases due to lesion characteristics or the timing of sampling may result in false-negative NMP-2 assays.

Individual risk assessment in bladder cancer patients based on a multi-marker panel

PURPOSE

To investigate whether a combined application of urine cytology (CYT) and molecular markers for bladder cancer (BC) can predict tumor aggressiveness.

METHODS

The study comprised 2,113 patients who underwent urethrocystoscopy and transurethral resection of the bladder. CYT, fluorescence in situ hybridization (FISH), immunocytology (uCyt+) and nuclear matrix protein 22 test (NMP22-ELISA) were performed. Results of the individual tests and of a multi-marker panel were correlated with pT-stages and tumor grades.

RESULTS

Five hundred and two of 2,113 (23.8 %) patients had BC. False-negative test rates of CYT (p < 0.001), FISH (p = 0.01) and NMP22-ELISA (p = 0.05) were lower in patients with muscle-invasive BC compared with patients with non-muscle-invasive BC. Furthermore, false-negative rates of CYT (p < 0.001), FISH (p = 0.0002) and NMP22-ELISA (p < 0.001) were lower in patients with G3/CIS compared with patients with G1-G2 BC. In patients with evidence of tumor in urethrocystoscopy, the presence of simultaneously positive CYT and NMP22 was associated with a 20-fold risk for G3/CIS (p < 0.0001).

CONCLUSIONS

This is the first study investigating the combined use of four urine markers in addition to cystoscopy to predict tumor aggressiveness. Our results indicate that combined application of urine markers as an adjunct to cystoscopy may facilitate identification of patients harboring high-grade tumors.

Influence of age on false positive rates of urine-based tumor markers

INTRODUCTION

Several influencing factors on false positive rates (FPRs) of urine-based tumor markers in the detection of urothelial cancer (UC) have been identified. We evaluated age as a possible influencing factor.

METHODS

Urinary cytology (Cyt), UroVysion (FISH), ImmunoCyt (uCyt+) and NMP22 were determined in 1,554 patients suspicious for UC of the bladder before cystoscopy and in case of cancer detection before TURB. Additionally, upper urinary tract imaging was performed. Maker sensitivity, specificity and FPRs were evaluated in the entire cohort and in subgroups divided by age into <50, ≥ 50-70 and ≥ 70 years. Contingency tables and the Cochrane Armitage tests were used for statistical comparisons.

RESULTS

UC was found in 377 and no UC in 1,177 (75 %) patients. A total of 336 patients were diagnosed with UC of the bladder and 41 with UC of the upper urinary tract. Overall sensitivity and specificity for Cyt were 82 and 82 %: for FISH, 73 and 79 % and for uCyt+, 79 and 75 %, respectively. For NMP22, regardless of the exclusion criteria they were 72 and 34 % and after exclusion of urinary tract infection (UTI) or prior to manipulation 46 and 86 %, respectively. Significantly higher FPRs were found with increasing age for Cyt (p = 0.001), a trend to higher FPRs for uCyt+ (p = 0.11) and almost no difference for FISH (p = 0.63). For NMP22, differences became significant after exclusion of patients with UTI or prior manipulation (p = 0.02).

CONCLUSIONS

The results of the present study give evidence that false positive rates of Cyt and NMP22 increase with age indicating that age should be respected for their correct interpretation.

Performance of survivin mRNA as a biomarker for bladder cancer in the prospective study UroScreen

Background

Urinary biomarkers have the potential to improve the early detection of bladder cancer. Most of the various known markers, however, have only been evaluated in studies with cross-sectional design. For proper validation a longitudinal design would be preferable. We used the prospective study UroScreen to evaluate survivin, a potential biomarker that has multiple functions in carcinogenesis.

Methods/Results

Survivin was analyzed in 5,716 urine samples from 1,540 chemical workers previously exposed to aromatic amines. The workers participated in a surveillance program with yearly examinations between 2003 and 2010. RNA was extracted from urinary cells and survivin was determined by Real-Time PCR. During the study, 19 bladder tumors were detected. Multivariate generalized estimation equation (GEE) models showed that β-actin, representing RNA yield and quality, had the strongest influence on survivin positivity. Inflammation, hematuria and smoking did not confound the results. Survivin had a sensitivity of 21.1% for all and 36.4% for high-grade tumors. Specificity was 97.5%, the positive predictive value (PPV) 9.5%, and the negative predictive value (NPV) 99.0%.

Conclusions

In this prospective and so far largest study on survivin, the marker showed a good NPV and specificity but a low PPV and sensitivity. This was partly due to the low number of cases, which limits the validity of the results. Compliance, urine quality, problems with the assay, and mRNA stability influenced the performance of survivin. However, most issues could be addressed with a more reliable assay in the future. One important finding is that survivin was not influenced by confounders like inflammation and exhibited a relatively low number of false-positives. Therefore, despite the low sensitivity, survivin may still be considered as a component of a multimarker panel.