Non-invasive molecular detection of bladder cancer recurrence

Microsatellite Instability in Urine: Breakthrough Method for Bladder Cancer Identification

Bladder cancer (BC) is the most common neoplasm of the urinary system and ranks tenth in global cancer incidence. Due to its high recurrence rate and the need for continuous monitoring, it is the cancer with the highest cost per patient. Cystoscopy is the traditional method for its detection and surveillance; however, this is an invasive technique, while non-invasive methods, such as cytology, have a limited sensitivity. For this reason, new non-invasive strategies have emerged, analyzing useful markers for BC detection from urine samples. The identification of tumor markers is essential for early cancer detection and treatment. Urine analysis offers a non-invasive method to identify these markers. Microsatellite instability (MSI) has been proposed as a promising marker for tumor cell detection and guided targeted therapies. Therefore, this review aims to explore the evidence supporting the identification of MSI in exfoliated bladder tumor cells (EBTCs) in the urine, emphasizing its potential as a non-invasive and clinically effective alternative for tumor identification. Furthermore, establishing clinical guidelines is crucial for standardizing its application in oncological screening and validating its clinical utility.

Results Obtained from a Pivotal Validation Trial of a Microsatellite Analysis (MSA) Assay for Bladder Cancer Detection through a Statistical Approach Using a Four-Stage Pipeline of Modern Machine Learning Techniques

Several studies have shown that microsatellite changes can be profiled in urine for the detection of bladder cancer. The use of microsatellite analysis (MSA) for bladder cancer detection requires a comprehensive analysis of as many as 15 to 20 markers, based on the amplification and interpretations of many individual MSA markers, and it can be technically challenging. Here, to develop fast, more efficient, standardized, and less costly MSA for the detection of bladder cancer, we developed three multiplex-polymerase-chain-reaction-(PCR)-based MSA assays, all of which were analyzed via a genetic analyzer. First, we selected 16 MSA markers based on 9 selected publications. Based on samples from Johns Hopkins University (the JHU sample, the first set sample), we developed an MSA based on triplet, three-tube-based multiplex PCR (a Triplet MSA assay). The discovery, validation, and translation of biomarkers for the early detection of cancer are the primary focuses of the Early Detection Research Network (EDRN), an initiative of the National Cancer Institute (NCI). A prospective study sponsored by the EDRN was undertaken to determine the efficacy of a novel set of MSA markers for the early detection of bladder cancer. This work and data analysis were performed through a collaboration between academics and industry partners. In the current study, we undertook a re-analysis of the primary data from the Compass study to enhance the predictive power of the dataset in bladder cancer diagnosis. Using a four-stage pipeline of modern machine learning techniques, including outlier removal with a nonlinear model, correcting for majority/minority class imbalance, feature engineering, and the use of a model-derived variable importance measure to select predictors, we were able to increase the utility of the original dataset to predict the occurrence of bladder cancer. The results of this analysis showed an increase in accuracy (85%), sensitivity (82%), and specificity (83%) compared to the original analysis. The re-analysis of the EDRN study results using machine learning statistical analysis proved to achieve an appropriate level of accuracy, sensitivity, and specificity to support the use of the MSA for bladder cancer detection and monitoring. This assay can be a significant addition to the tools urologists use to both detect primary bladder cancers and monitor recurrent bladder cancer.

Qualification of the Microsatellite Instability Analysis (MSA) for Bladder Cancer Detection: The Technical Challenges of Concordance Analysis

Bladder cancer (here we refer to transitional carcinoma of bladder) is a major cause of morbidity and mortality in the Western world, and recent understanding of its etiology, the molecular characteristics associated with its progression, renders bladder cancer an ideal candidate for screening. Cystoscopy is invasive and sometimes carries unwanted complications, but it is the gold standard for the detection of bladder cancer. Urine cytology, while the most commonly used test as an initial screening tool, is of limited value due to its low sensitivity, particularly for low-grade tumors. Several new "molecular assays" for the diagnosis of urothelial cancer have been developed over the last two decades. Here, we have established our new bladder cancer test based on an assay established for the Early Detection Research Network (EDRN) study. As a part of the study, a quality control CLIA/College of American Pathology (CAP) accredited laboratory, (QA Lab), University of Maryland Baltimore Biomarker Reference Laboratory (UMB-BRL), performed quality assurance analysis. Quality assurance measures included a concordance study between the testing laboratory (AIBioTech), also CLIA/CAP accredited, and the QA lab to ensure that the assay was performed and the results were analyzed in a consistent manner. Therefore, following the technical transfer and training of the microsatellite analysis assay to the UMB-BRL and prior to the initiation of analysis of the clinical samples by the testing lab, a series of qualification studies were performed. This report details the steps taken to ensure qualification of the assay and illustrates the technical challenges facing biomarker validation of this kind.

Development of Multiplex Polymerase Chain Reaction (PCR)-Based MSA Assay for Bladder Cancer Detection

Several studies have shown that microsatellite changes can be profiled in the urine to detect bladder cancer. Microsatellite analysis (MSA) of bladder cancer detection requires a comprehensive analysis of up to 15-20 markers based on amplifying and interpreting many individual MSA markers, which can be technically challenging. To develop fast, efficient, standardized, and less costly MSA to detect bladder cancer, we developed three multiplex polymerase chain reaction (PCR) based MSA assays, all of which were analyzed by a genetic analyzer. First, we selected 16 MSA markers based on nine publications. We developed MSA assays based on triplet or three-tube-based multiplex PCR (Triplet MSA assay) using samples from Johns Hopkins University (JHU Sample, first set of samples). In the second set of samples (samples from six cancer patients and fourteen healthy individuals), our Triplet Assay with 15 MSA markers correctly predicted all 6/6 cancer samples to be cancerous and 14/14 healthy samples to be healthy. Although we could improve our report with more clinical information from patient samples and an increased number of cancer patients, our overall results suggest that our Triplet MSA Assay combined with a genetic analyzer is a potentially time- and cost-effective genetic assay for bladder cancer detection and has potential use as a dependable assay in patient care.

Microsatellite Instability Analysis (MSA) for Bladder Cancer: Past History and Future Directions

Microsatellite instability (MSI), the spontaneous loss or gain of nucleotides from repetitive DNA tracts, is a diagnostic phenotype for gastrointestinal, endometrial, colorectal, and bladder cancers; yet a landscape of instability events across a wider variety of cancer types is beginning to be discovered. The epigenetic inactivation of the MLH1 gene is often associated with sporadic MSI cancers. Recent next-generation sequencing (NGS)-based analyses have comprehensively characterized MSI-positive (MSI+) cancers, and several approaches to the detection of the MSI phenotype of tumors using NGS have been developed. Bladder cancer (here we refer to transitional carcinoma of the bladder) is a major cause of morbidity and mortality in the Western world. Cystoscopy, a gold standard for the detection of bladder cancer, is invasive and sometimes carries unwanted complications, while its cost is relatively high. Urine cytology is of limited value due to its low sensitivity, particularly to low-grade tumors. Therefore, over the last two decades, several new "molecular assays" for the diagnosis of urothelial cancer have been developed. Here, we provide an update on the development of a microsatellite instability assay (MSA) and the development of MSA associated with bladder cancers, focusing on findings obtained from urine analysis from bladder cancer patients as compared with individuals without bladder cancer. In our review, based on over 18 publications with approximately 900 sample cohorts, we provide the sensitivity (87% to 90%) and specificity (94% to 98%) of MSA. We also provide a comparative analysis between MSA and other assays, as well as discussing the details of four different FDA-approved assays. We conclude that MSA is a potentially powerful test for bladder cancer detection and may improve the quality of life of bladder cancer patients.

Screening and diagnosis of endometrial cancer in Lynch syndrome

Lynch syndrome (LS) is an autosomal dominant inherited cancer predisposition syndrome caused by a mismatch of DNA repair (MMR system). Lifetime risk of developing endometrial and ovarian cancer in LS is higher than in the general population and gynecologic screening appears interesting. Screening is based on several tests: pelvic ultrasound, endometrial biopsy and hysteroscopy for endometrial cancer, pelvic ultrasound and CA125 for ovarian cancer. Those tests appear efficient for the diagnosis of gynecologic cancers in LS. Nevertheless, screening tests have not proved clinical benefit until now, and potential problems of compliance, risk of false negative cases, and interval cancer associated with screening do justify offering prophylactic surgery to patients. Women with LS should be informed of the potential benefits and risks of screening and the importance of evaluation in case of gynecologic symptoms or abnormal bleeding. Chemoprevention by progestin-containing oral contraceptives and the treatment of premalignant lesion are available options for reducing the risk of endometrial cancer in LS population.

Meta-analysis reveals a lack of association between UGT2B17 deletion polymorphism and tumor susceptibility

Purpose

UGT2B17 is a vital member of the UGT2 family and functions as a detoxification enzyme which catalyzes the glucuronidation of lipophilic compounds. Accumulating evidences implicates that it may contribute to the susceptibility of tumor risk. Identification of a UGT2B17 deletion polymorphism has attracted studies to evaluate the association between the UGT2B17 deletion polymorphism and tumor risk in diverse populations. However, the available results are conflicting.

Methods

A meta-analysis based on 14 studies from 10 publications including 5,732 cases and 5,112 controls was performed. Published literature from PubMed, EMBASE and Web of Science was pooled and the crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate the strength of the associations.

Results

Conclusively, our results indicate that individuals with a UGT2B17 deletion polymorphism were associated with tumor risks (OR = 1.29, 95% CI = 1.03–1.63, P<0.001) in a recessive model. However, after excluding two studies for their heterogeneity, the result then demonstrated that the UGT2B17 deletion polymorphism was not associated with tumor risks (OR = 1.118, 95%CI = 0.938–1.332, P>0.1). A subgroup analysis based on tumor type, sex or race did not show significant results.

Conclusion

These results suggest that the UGT2B17 deletion polymorphism is not associated with tumor risks.

Intestinal type villous adenoma of the renal pelvis

Intestinal type villous adenomas are uncommon in the genitourinary tract. Most reported cases have been located in the urinary bladder or urachus. Villous adenoma arising in the renal pelvis or ureter is very rare. We present a case of an 81-year-old female who presented with difficulty voiding and mucosuria. A computed tomography scan identified right-sided hydronephrosis, renal parenchymal atrophy, nonobstructing calculi and a lower pole renal mass. She underwent open right nephrectomy. Histopathologic examination of the kidney revealed an intestinal type villous adenoma of the renal pelvis with high-grade dysplasia and focal areas suspicious for invasive adenocarcinoma. We review the four previously reported cases of intestinal type villous adenoma in the renal pelvis and discuss diagnosis and management of this unusual neoplasm.

Microsatellite instability analysis in uterine cavity washings as a screening tool for endometrial cancer in Lynch syndrome

Although patients with Lynch syndrome (LS) are at high risk of endometrial cancer, gynecologic screening has been poorly investigated and diagnostic value of current screening tests remains unclear. Microsatellite instability (MSI) phenotype is found in more than 90% of endometrial cancers developed in LS patients. Here we report the first two cases of unstable endometrial tumors with detection of MSI in uterine cavity washings cells. This new technique may be a promising screening tool in LS.

Diagnostic, staging, and grading of urothelial carcinomas from urine: performance of BCA-1, a mini-array comparative genomic hybridisation-based test

BACKGROUND

Cytogenetic abnormalities occur at an early stage of bladder urothelial carcinomas (BUC), and their frequency increases as the cancer becomes more advanced.

OBJECTIVE

To assess the diagnostic performance of a test based on cytogenetic abnormalities to diagnose, stage, and grade BUC from the urine.

DESIGN, SETTING, AND PARTICIPANTS

We used a 341 bacterial artificial chromosome (BAC) comparative genomic hybridisation (CGH)-array chip (BCA-1) designed to include loci affected in BUC. The chip was first used on 32 frozen BUC biopsies to design staging (BN0) and grading (BN1 and BN2) prediction models based on Bayesian networks analysis. The models were then validated on external data obtained from 98 tumour samples using a 2464 BAC CGH-array chip. The performance of the test was finally assessed on 44 urine pellets collected, including 22 patients who had BUC and 22 controls.

MEASUREMENTS

We measured sensitivity and specificity to diagnose BUC stage and grade from urine pellets.

RESULTS AND LIMITATIONS

In the urine, BCA-1 test sensitivity was 95%, specificity was 86%, and accuracy was 91%. The BN0 staging model identified T1-4 tumours in the urine with a sensitivity of 90%, a specificity of 83%, and an accuracy of 87%. The BN1 and BN2 grading models detected high-grade disease with a sensitivity, specificity, and accuracy of 86%, 88%, and 87%, respectively, using BN1 and 100%, 63%, and 82%, respectively, using BN2. BN models performed with similar sensitivity but reduced specificity using the external data. BCA-1 failed to produce results for eight additional samples (failure rate: 9%). The test needed high quantities and quality of DNA, and external validation in larger, prospective, and better-designed studies is necessary to confirm feasibility and performance.

CONCLUSIONS

The BCA-1 mini-CGH-array chip detected BUC in urine with a high diagnostic performance. It could also accurately discriminate low-grade from high-grade tumours and, to a lesser extent, lamina propria-invasive tumours from pTa tumours.

Prognostic value of loss of heterozygosity at chromosome 9p in non-muscle-invasive bladder cancer

OBJECTIVE

To investigate the prognostic value of loss of heterozygosity (LOH) at chromosome 9p in patients with non-muscle-invasive bladder cancer (NMI-BC).

METHODS

Between 2000 and 2006, we included in the study 84 patients with NMI-BC. LOH analyses were performed on tumor tissue using 3 microsatellite markers at chromosome 9p. Associations of LOH with recurrence and progression of the tumors were evaluated.

RESULTS

Frequency of LOH at 9p was 11.1%, 29.0%, and 31.6% in pTaG1, pTaG2, and pT1G3 tumors, respectively. Recurrence occurred in 27 patients. None of the markers was able to predict recurrence. Progression occurred in 9.5% of the cases, with progression to muscle-invasive bladder cancer (MI-BC) in 4.8% of the cases. LOH at IFN-alpha was significantly associated with progression to MI-BC (P = .006). In the case of LOH at IFN-alpha, 2-year progression-free survival and progression-free survival to MI-BC were both 59.3%, compared with 97.1% and 98.6%, respectively, in case of conservation of LOH in multivariable analysis, LOH at IFN-alpha remained statistically associated with progression and progression to MI-BC. LOH at IFN-alpha was a significant and independent predicting factor of progression and progression to MI-BC, with P = .05 and 0.01 (HR 4.8 for progression; HR 24.2 for muscle invasion).

CONCLUSIONS

Our study suggests that LOH at IFN-alpha is an independent prognostic factor for progression to MI-BC. LOH analysis of bladder tumors may help in the management of NMI-BC. Specifically, it could be of use in selecting patients for early aggressive treatment and/or in planning close follow-up schedule.

Quantitative loss of heterozygosity analysis for urothelial carcinoma detection and prognosis

OBJECTIVES

To evaluate loss of heterozygosity (LOH) using microsatellite polymorphism analysis as a diagnostic and prognostic marker at the time of transurethral resection and as a follow-up marker preceding cystoscopic evidence of recurrence compared with cytology.

METHODS

A total of 127 urothelial carcinoma (UC) patients were included. Tumors were staged and graded according to the International Union Against Cancer-tumor, node, metastases system and to the 2004 World Health Organization classification. LOH urinalysis was performed using 8 markers and marker-specific LOH thresholds. Thirty control samples, obtained from healthy volunteers, were used to determine the positive cut-off for each marker.

RESULTS

LOH was significantly more sensitive than cytology in low-grade (64.8% vs 38.5%, P <.001) and low-stage UC (68.6% vs 45.5%, P <.001). The cumulative sensitivity of cytology and LOH reached 74.7% (P <.001) for low-grade and 80.2% (P <.001) for low-stage tumors. Both urinary LOH at TP53 and chromosome 9p markers were associated with an increased risk of recurrence (relative risk = 1.73 [1.30-2.31], P = .0002) and occurred more frequently in the initial urine samples of patients who later relapsed from primary tumors (36.4% vs 0.0%, P <.05 and 57.6% vs 15.8%, P = .0001). Among 32 relapse patients, LOH was positive alongside cystoscopy in 25 of 32 cases and tested positive before cystoscopy detected recurrence in a further 5 of 25 cases.

CONCLUSIONS

UC diagnosis and monitoring would greatly benefit from supplementing conventional cytology with LOH urinalysis, using a panel of 8 microsatellite markers with specific threshold levels. Given the limitations of both cystoscopy and cytology, novel molecular markers are needed for detection and follow-up of UC.

TP53 codon 72 polymorphism and cervical cancer: a pooled analysis of individual data from 49 studies

BACKGROUND

Cervical cancer is caused primarily by human papillomaviruses (HPV). The polymorphism rs1042522 at codon 72 of the TP53 tumour-suppressor gene has been investigated as a genetic cofactor. More than 80 studies were done between 1998 and 2006, after it was initially reported that women who are homozygous for the arginine allele had a risk for cervical cancer seven times higher than women who were heterozygous for the allele. However, results have been inconsistent. Here we analyse pooled data from 49 studies to determine whether there is an association between TP53 codon 72 polymorphism and cervical cancer.

METHODS

Individual data on 7946 cases and 7888 controls from 49 different studies worldwide were reanalysed. Odds ratios (OR) were estimated using logistic regression, stratifying by study and ethnic origin. Subgroup analyses were done for infection with HPV, ethnic origin, Hardy-Weinberg equilibrium, study quality, and the material used to determine TP53 genotype.

FINDINGS

The pooled estimates (OR) for invasive cervical cancer were 1.22 (95% CI 1.08-1.39) for arginine homozygotes compared with heterozygotes, and 1.13 (0.94-1.35) for arginine homozygotes versus proline homozygotes. Subgroup analyses showed significant excess risks only in studies where controls were not in Hardy-Weinberg equilibrium (1.71 [1.21-2.42] for arginine homozygotes compared with heterozygotes), in non-epidemiological studies (1.35 [1.15-1.58] for arginine homozygotes compared with heterozygotes), and in studies where TP53 genotype was determined from tumour tissue (1.39 [1.13-1.73] for arginine homozygotes compared with heterozygotes). Null results were noted in studies with sound epidemiological design and conduct (1.06 [0.87-1.29] for arginine homozygotes compared with heterozygotes), and studies in which TP53 genotype was determined from white blood cells (1.06 [0.87-1.29] for arginine homozygotes compared with heterozygotes).

INTERPRETATION

Subgroup analyses indicated that excess risks were most likely not due to clinical or biological factors, but to errors in study methods. No association was found between cervical cancer and TP53 codon 72 polymorphism when the analysis was restricted to methodologically sound studies.

FUNDING

German Research Foundation (DFG).

DNA microarray expression profiling of bladder cancer allows identification of noninvasive diagnostic markers

PURPOSE

There is a need in urological practice to identify new bladder cancer molecular markers to further develop noninvasive diagnostic tests. We analyzed bladder cancer gene expression profiles to determine the relevant differentially expressed genes and whether this differential expression is maintained in urine samples.

MATERIALS AND METHODS

We collected 55 tissue specimens from a total of 43 patients with bladder cancer and 12 controls, and 49 urine samples from bladder washings from a total of 36 patients with bladder cancer and 13 controls between September 2003 and December 2004. DNA microarrays (GeneChip Human Genome U133 Plus 2.0 Array) were used to identify differentially expressed genes at 3 bladder cancer stages. Selected differentially expressed genes were validated in an independent set of bladder washings by quantitative reverse transcriptase-polymerase chain reaction.

RESULTS

Unsupervised cluster analysis of DNA microarray data showed a clear distinction in control vs tumor samples and low vs high grade tumors. Genes with at least 2-fold differential expression in controls vs tumors (2,937 probe sets or 2,295 genes) and in low vs high grade tumors (674 probe sets or 530 genes) were identified and ranked. Gene expression measurements in bladder washings of the 6 most differentially expressed genes in controls vs tumors were confirmed for the 2 over expressed genes tested by quantitative reverse transcriptase-polymerase chain reaction. All 8 selected differentially expressed genes in low vs high grade tumors were confirmed in bladder washing samples.

CONCLUSIONS

Bladder cancer analysis by DNA microarrays provides new putative mRNA markers for bladder cancer diagnosis and/or prognosis that can be extrapolated to bladder fluids.

Bladder cancer biomarkers and their role in surveillance and screening

Early detection of bladder cancer and its recurrences is essential for improved prognosis and long-term survival. The detection and follow-up of these patients is currently based on cystoscopy, which is expensive and invasive, and, in most cases, cytology, which is non-invasive but not very sensitive. During recent years, many urine-based tests have been developed and tested in different patient populations. In this review we discuss new developments for biomarkers in bladder cancer that have potential use in surveillance and screening. In almost all publications authors compare sensitivity of the test with a concomitantly executed cystoscopy, for example, determine cross-sectional sensitivity. However, it has also been shown that false positive test results may be followed by a positive cystoscopy in the near future, showing that cystoscopy itself does not provide 100% sensitivity. This suggests that for a proper evaluation of urine-based tests, longitudinal studies should be carried out and the results communicated to the urologist.

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.

Microsatellite analysis of voided-urine samples for surveillance of low-grade non-muscle-invasive urothelial carcinoma: feasibility and clinical utility in a prospective multicenter study (Cost-Effectiveness of Follow-Up of Urinary Bladder Cancer trial [CEFUB])

BACKGROUND

Microsatellite analysis (MA) of voided-urine samples has been promoted as an alternative for cystoscopy surveillance (UCS) of patients with low-grade non-muscle-invasive papillary urothelial carcinoma (UC).

OBJECTIVE

To assess the feasibility and clinical utility of MA on voided-urine samples in a routine setting to detect or predict bladder cancer recurrences.

DESIGN, SETTING, AND PARTICIPANTS

We evaluated 228 patients monitored by MA of voided-urine samples and synchronous UCS who participated in a longitudinal prospective study in 10 hospitals. Follow-up started after diagnosis of a primary or recurrent pTa, pT1, grade 1 or grade 2 papillary UC.

MEASUREMENTS

Clinico-pathological parameters and fibroblast growth factor receptor 3 (FGFR3) gene mutation status of the inclusion tumour were determined. MA outcome was analysed in 1012 urine samples during a mean follow-up of 41 mo. Poor DNA quality prevented MA in 19% (197/1012) of the samples, leaving 815 visits for a cross-sectional analysis of sensitivity and specificity. We determined the predictive value (PPV) in a longitudinal analysis for 458 series with persistent MA results. Factors influencing diagnostic quality of MA were investigated. Kaplan-Meier analysis was performed to relate MA results to recurrence.

RESULTS AND LIMITATIONS

Cross-sectional sensitivity and specificity of MA for detection of a recurrence were 58% (49/84) and 73% (531/731), respectively. One pT1 grade 3 UC was missed. In a longitudinal analysis, the 2-yr risk to develop a recurrence reached 83% if MA outcome was persistently positive and 22% when MA was persistently negative. PPV of MA was higher with wild-type FGFR3 gene status and smoking habits. All four upper urinary tract tumours detected were preceded by a positive MA test.

CONCLUSIONS

Consecutive positive MA results are a strong predictor for future recurrences, but sensitivity needs to be improved, for example, by patient selection and testing of additional genetic markers in urine samples.

A comparison of the performance of microsatellite and methylation urine analysis for predicting the recurrence of urothelial cell carcinoma, and definition of a set of markers by Bayesian network analysis

OBJECTIVE

To compare the potential of two diagnostic methods for detecting recurrence of urothelial cell carcinoma (UCC) of the bladder, by (i) detecting alterations in microsatellite DNA markers and loss of heterozygosity (LOH), and (ii) detecting aberrant gene hypermethylation, as UCC has a high recurrence rate in the urinary tract and the disease can invade muscle if new tumours are overlooked.

PATIENTS AND METHODS

Over 1 year, urine samples were retrieved from 40 patients already diagnosed with bladder UCC (30 pTa, two pTis, eight pT1). Samples were collected 6 months after bladder tumour resection, during the follow-up schedule. We used samples to analyse nine microsatellite markers and the methylation status of 11 gene promoters. Receiver operating characteristic curves were generated and Bayesian statistics used to create an interaction network between recurrence and the biomarkers.

RESULTS

During the study, 15 of the 40 patients (38%) had a tumour recurrence and 14 were identified by cystoscopy (reference method). Overall, microsatellite markers (area under curve, AUC 0.819, 95% confidence interval, CI, 0.677-0.961) had better performance characteristics than promoter hypermethylation (AUC 0.448, 0.259-0.637) for detecting recurrence. A marker panel of IFNA, MBP, ACTBP2, D9S162 and of RASSF1A, and WIF1 generated a higher diagnostic accuracy of 86% (AUC 0.92, 0.772-0.981).

CONCLUSION

Microsatellite markers have better performance characteristics than promoter hypermethylation for detecting UCC recurrence. These data support the further development of a combination of only six markers from both methods in urinary DNA. Once validated, it could be used routinely during the follow-up for the early detection and surveillance of UCC from the lower and upper urinary tract.

TGF-betaRII, BAX, IGFIIR, caspase-5, hMSH3 and hMSH6 alterations are not associated with microsatellite instability or p53 mutations in invasive urothelial carcinoma of the urinary bladder

AIM

The aim of this study was to determine the potential synchronous contribution of alterations in TGF-betaRII, BAX, IGFIIR, caspase-5, hMSH3 and hMSH6 genes to the development and clinical outcome of bladder cancer, in relation to p53 mutations, microsatellite status and hMLH1/hMSH2 expression.

METHODS

Molecular biology techniques as well as immunohistochemistry were applied in 69 samples from patients with urothelial carcinoma.

RESULTS

Microsatellite alterations were observed in TGF-betaRII(A)(10 )(16%) and BAX(G)(8 )(3%), irrespective of the presence of p53 mutations, but not in IGFIIR(G)(8), caspase-5(A)(10, ) hMSH3(A)(8) and hMSH6(C)(8). A statistically significant correlation could be found only between hMLH1 expression and the presence of microsatellite instability (Fisher's exact test, p = 0,013). Survival analysis indicated that apart from grade and T-category, hMLH1 expression was the only parameter significantly affecting overall survival (p = 0.021 in univariate and p = 0.015 in multivariate analysis) and recurrence-free survival (p = 0.0463 in univariate and p = 0.022 in multivariate analysis).

CONCLUSIONS

We conclude that alterations of the examined target genes of MSI are rare in urinary bladder carcinoma and they are not associated with microsatellite instability or the presence of p53 mutations.

Patients' perceived burden of cystoscopic and urinary surveillance of bladder cancer: a randomized comparison

OBJECTIVE

To compare, in patients with non-muscle-invasive low-grade (pTa/pT1, G1/G2) urothelial cell carcinoma of the urinary bladder, the perceived burden of flexible cystoscopy or surveillance by microsatellite analysis (MA) in voided urine, as such patients are normally recommended to adhere to regular cysto-urethroscopic surveillance (CUS).

PATIENTS AND METHODS

In all, 220 participants of a randomized trial comparing CUS and surveillance by MA were asked to complete questionnaires 1 week after cystoscopy or urine sample collection. We assessed the discomfort and pain reported during CUS, experiences with MA, and physical symptoms, medical consumption and general functioning in the week after CUS/urine sampling.

RESULTS

We analysed data from 732 questionnaires (197 patients) completed after CUS and 184 (67 patients) after collecting urine. The introduction of the cystoscope was reported to cause discomfort in 39% and pain in 35% of the responses to the questionnaires; the waiting time for the results of MA was reported as burdensome in 19%. Painful micturition was significantly more frequent in the week after CUS than after MA (30% and 12%, respectively). The frequency of fever (1% and 2%) and haematuria (7% and 6%) was similar in both groups. Older patients reported significantly less pain and discomfort from cystoscopy, and this was not related to having more previous cystoscopies.

CONCLUSION

CUS caused pain and discomfort in about a third of patients. The burden of MA appeared fully attributable to the waiting time for the test result. The present results are a further motivation in the search for less invasive surveillance tests.

Utility of a multiprobe fluorescence in situ hybridization assay in the detection of superficial urothelial bladder cancer

We evaluated the performance of a multiprobe FISH (fluorescence in situ hybridization) assay for noninvasive detection of superficial urothelial carcinoma (UC) in the bladder, in comparison to urinary cytology. Voided urine samples from 74 patients with superficial UC were analyzed by both techniques. Urine samples from 19 patients with muscle-invasive tumors and from 19 healthy control subjects were also studied. For FISH analysis, labeled probes for chromosomes 3, 7, 9, and 17 were used to assess chromosomal abnormalities indicative of malignancy. We found a significant difference between the overall sensitivity of FISH and cytology in superficial UC detection (70.3 versus 35.1%, respectively; P < 0.0001). This significant difference was maintained when superficial UCs were broken down into low grade (52.8 versus 13.9%, respectively; P < 0.0005) and high grade (86.8 versus 55.3%, respectively; P < 0.0015) tumors. Overall specificity was 100% for cytology and 94.7% for FISH (difference not significant). Of patients with suspicious cytology, 69% were positive by FISH. Together, these findings suggest that FISH assay for chromosomes 3, 7, 9, and 17 has a higher sensitivity than cytology and a similar specificity in the detection of superficial UC--which could be useful for reducing some cystoscopies in the accurate follow-up usually performed in these patients.

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.

Bladder cancer diagnosis and recurrence prognosis: Comparison of markers with emphasis on survivin

Expression of the anti-apoptotic protein survivin is hardly detectable or even absent in many differentiated adult tissues, but is upregulated in almost any type of cancer. Furthermore, high survivin mRNA or protein expression generally correlates with an adverse disease course. Both these important features of survivin expression have been investigated for diagnostic and prognostic purposes in many human cancers, including bladder cancer. In this review, the role of survivin in the detection of bladder tumors and the prediction of tumor recurrence in patients with superficial bladder cancer will be discussed and compared to that of other markers/tests. The most promising marker(s) will be outlined. Also, important requirements for a successful implementation of such markers in a hospital setting are discussed. Finally, future directions for the discovery of new diagnostic or prognostic candidate markers will be mentioned.

Quantitative molecular urinary cytology by fluorescence in situ hybridization: a tool for tailoring surveillance of patients with superficial bladder cancer?

OBJECTIVE

To determine whether it is possible to stratify patients with superficial bladder cancer into low- and high-risk groups for tumour recurrence/progression based on the chromosomal pattern detected by fluorescence in situ hybridization (FISH) in one urine cytology specimen used for follow-up testing.

PATIENTS AND METHODS

Voided urine samples from 47 consecutive patients with urinary tract neoplasms (13 with no history of urothelial malignancy and 34 under follow-up after complete transurethral resection of superficial urothelial carcinoma of the bladder) were evaluated by liquid-based cytology (ThinPrep(R), CYTYC Corp., Boxborough, MA, USA) and UroVysion FISH (Vysis-Abbott, Downers Grove, IL).

RESULTS

Of the 34 patients under surveillance, the UroVysion test was negative in four, 17 had loss of 9p21 sequences either alone or combined with low-frequency trisomy/ies or tetrasomy/ies of chromosomes 3, 7 and 17 in single cells (low-risk FISH), and 13 also had complex aneusomies of the remaining chromosomes (high-risk FISH). One of the four FISH-negative neoplasms, four of the 17 low-risk FISH cases and five of the 11 informative high-risk FISH-positive patients developed recurrence. Progression occurred only in patients with high-risk FISH results, showing high-frequency complex chromosomal polysomies (four of 11).

CONCLUSION

The results from this pilot study indicate that the UroVysion FISH test may help to individually assess the clinical behaviour of superficial bladder cancer, based on the chromosomal pattern of exfoliated tumour cells in follow-up urinary cytology. It might be of use to identify those patients likely to progress at earlier and curable stages of disease, and lengthen the surveillance period in those with persistent or recurrent low-risk disease.

Microsatellite instability as predictor of survival in patients with invasive upper urinary tract transitional cell carcinoma

OBJECTIVES

To establish whether high microsatellite instability (MSI) (present in almost 20% of cases) and loss of MSH2 protein expression (sometimes used to predict MSI status) are prognostic factors of overall survival for patients with invasive upper urinary tract transitional cell carcinoma (UUT-TCC). UUT-TCC has a poor prognosis (overall survival less than 50% at 5 years).

METHODS

The files of 80 patients who underwent nephroureterectomy for invasive UUT-TCC (Stage pT2 or worse) between 1990 and 2002 were reviewed. The following data were collated: age at diagnosis, prior history of cancer, tobacco consumption, tumor stage and grade, and disease progression. MSI was determined by polymerase chain reaction/fragment analysis and MSH2 protein expression by immunohistochemistry on retrieved tumor tissue.

RESULTS

The median patient age was 71.5 years. The male/female ratio was 2.8. High MSI and loss of MSH2 expression were encountered in the tumors of 14 (17%) and 21 (26%) of the 80 patients, respectively. High MSI was significantly associated with patients with a better prognosis (Stage T2-T3N0M0; P = 0.02). The mean overall survival was 22.5 +/- 18 months (range 6 to 78). In univariate analyses, age, stage, tumor grade, high MSI, and loss of MSH2 expression were related to better overall survival (37 +/- 22 months, P = 0.003; 34 +/- 22 months, P = 0.02). Only stage, age, and high MSI were prognostic factors in a multivariate analysis (P < 0.05).

CONCLUSIONS

MSI and expression of MSH2 are useful prognostic factors in invasive UUT-TCC. However, other than age and stage, only MSI was an independent factor. High MSI indicates a better prognosis, especially in patients younger than 71 years with Stage T2-T3N0M0.

Mononucleotide markers of microsatellite instability in carcinomas of the urinary bladder

AIMS

To determine the presence of microsatellite instability (MSI) and to assess the expression of the human mismatch repair (MMR) gene products hMLH1 and hMSH2 in primary transitional cell carcinomas (TCCs) of the urinary bladder in relation to clinico-pathological parameters.

METHODS

Seventy-two cases of primary TCC were screened for the presence of alterations in MSI markers by molecular techniques and evaluated immunohistochemically for the expression of hMLH1 and hMSH2 proteins. Clinical data were available in 70 cases. The percentage of MSI rose to 16.6%.

RESULTS

Reduced (<20%) hMLH1 expression was closely related to the presence of MSI (p=0.0004). Neither MMR proteins nor MSI was associated with grade, stage, papillary status. Clinical outcome analysed as a function of MSI did not show significant differences in terms of both disease-free and overall survival. Reduced hMLH1 expression was a significant predictor of shorter disease-free survival in univariate and multivariate analysis.

CONCLUSIONS

The presence of MSI is not related to classical clinico-pathological parameters in TCCs, nor does it appear to be of prognostic significance. hMLH1 was an important indicator for recurrence.

Molecular detection of noninvasive and invasive bladder tumor tissues and exfoliated cells by aberrant promoter methylation of laminin-5 encoding genes

Laminin-5 (LN5) anchors epithelial cells to the underlying basement membrane, and it is encoded by three distinct genes: LAMA3, LAMB3, and LAMC2. To metastasize and grow, cancer cells must invade and destroy the basement membrane. Our previous work has shown that epigenetic inactivation is a major mechanism of silencing LN5 genes in lung cancers. We extended our methylation studies to resected bladder tumors (n = 128) and exfoliated cell samples (bladder washes and voided urine; n = 71) and correlated the data with clinicopathologic findings. Nonmalignant urothelium had uniform expression of LN5 genes and lacked methylation. The methylation frequencies for LN5 genes in tumors were 21-45%, and there was excellent concordance between methylation in tumors and corresponding exfoliated cells. Methylation of LAMA3 and LAMB3 and the methylation index were correlated significantly with several parameters of poor prognosis (tumor grade, growth pattern, muscle invasion, tumor stage, and ploidy pattern), whereas methylation of LAMC2 and methylation index were associated with shortened patient survival. Of particular interest, methylation frequencies of LAMA3 helped to distinguish invasive (72%) from noninvasive (12%) tumors. These results suggest that methylation of LN5 genes has potential clinical applications in bladder cancers.

Microsatellite Instability in Urothelial Carcinoma of the Upper Urinary Tract

PURPOSE

Transitional cell carcinoma (TCC) of the upper urinary tract (TCC-UUT) may develop with high frequency in patients with hereditary nonpolyposis colorectal cancer syndrome. Tumors in patients with this syndrome show genomic lesions in DNA mismatch repair genes that are detectable as microsatellite instability (MSI). Because little is known about genetic lesions in TCC-UUT compared with bladder TCC, we determined the genetic profiles (MSI and allelic loss) in a series of 26 upper urinary tract tumors using 5 informative microsatellite markers.

MATERIALS AND METHODS

A total of 26 paraffin embedded samples from 24 patients with clinically diagnosed TCC-UUT (renal pelvis and/or ureter) were tested for loss of heterozygosity (LOH) and MSI with the dinucleotide markers D9S171 (9p21) and D5S346 (5q22), and the mononucleotide repeats BAT25 (4q12), BAT26 (2p16) and BAT40 (1p13.1).

RESULTS

MSI was detected at 1 or more microsatellite loci in 12 of the 26 tumors (46%). The markers BAT40, BAT25, BAT26, D9S171 and D5S346 showed instability in 7, 4, 4, 2 and 3 tumor samples, respectively. LOH at D9S171 was detected in 58% of the cases and 10 of the 14 tumors showing LOH were superficial. LOH at D5S346 occurred in 27% of the cases and it was a feature of invasive high grade TCC-UUT.

CONCLUSIONS

Frequent LOH at D9S171 in TCC-UUT confirms that LOH at 9p21 is not only observed in bladder TCC, but rather in whole urinary tract TCC. Furthermore, our study indicates a high level of MSI in TCC-UUT, although it is a rare event in bladder cancer. The establishment of distinct genetic profiles between upper and lower urinary tract tumors could provide an additional tool to improve diagnosis, disease monitoring and prediction of prognosis.

New diagnostic strategies in the detection and staging of bladder cancer

PURPOSE OF REVIEW

Bladder cancer is a very frequent disease and represents the second most common genitourinary neoplasm. The most prevalent form of the disease, superficial bladder cancer, can recur in more than 70% of cases, despite correct management. Any way to improve our disease diagnostic and treatment policy is therefore welcome.

RECENT FINDINGS

This review covers the following topics: (1). endoscopic tools: standard cystoscopy versus fluorescence cystoscopy and virtual endoscopy; (2). bladder cancer staging: histopathological analysis developments and imaging techniques (positron emission tomography, magnetic resonance imaging, computed tomography); (3). cytology and ancillary procedures (ImmunoCyt and fluorescence in-situ hybridization test, and others); (4). first-generation (bladder tumour antigen, nuclear matrix protein 22, telomerase repeat amplification protocol) and second-generation (loss of heterozygosity, minichromosome maintenance 5, DNA methylation, microsatellite) urine and serum markers.

SUMMARY

New diagnostic and therapeutic (endoscopic) tools in superficial bladder cancer should eventually modify our disease management policy. Fluorescence cystoscopy detects carcinoma in situ with a high accuracy, and seems to have a positive impact on reducing residual tumour and recurrence rate. A more specific staining of tissue specimens facilitates histological analysis and helps achieve better staging, especially in T1 diseases. Improving the sensitivity of cytology for low-grade diseases, ancillary procedures to classic cytology such as fluorescence in-situ hybridization and ImmunoCyt tests, may reduce the number of unpleasant cystoscopies in surveillance protocols of selected groups of patients. Second-generation urine markers such as loss of heterozygosity, microsatellite, minichromosome maintenance 5, with a high level of accuracy, show great potential for influencing bladder cancer detection and screening policy.

Combined intravesical hyperthermia and mitomycin chemotherapy: a preliminary in vivo study

Previous clinical studies of the combination of local intravesical hyperthermia with cytostatic drugs for the treatment of Superficial Transitional Cell Carcinoma of the urinary bladder (STCCB) showed encouraging results both in reducing recurrence rate to 20-30% within 2 years and in ablative success rate of 79%. Our objectives were to evaluate bladder tissue and adjacent organs during and following hyperthermia treatment. An intravesical catheter equipped with a radio-frequency antenna (Synergo SB-TS 101.1 System) was used for hyperthermia and intravesical chemotherapy (mitomycin C) was instilled in vivo for 60 min in two anaesthetized sheep. Thirteen to fifteen thermocouples were sewn surgically on the internal and external surfaces of the bladder wall and on adjacent organs to monitor the temperature during the treatment. We expected the intravesical temperature to be under 46 degrees C and the external layers below 45 degrees C. The bladder was filled with 50 mL of chemotherapeutic solution (400 micro g/mL of mitomycin C in distilled water). The sheep were sacrificed at the end of the treatment. Three other sheep, which underwent thoracic surgery, served as control group. Histological changes in both groups showed foci of oedema and haemorrhage with inflammation in the lamina propria and serosa. Foci of desquamation of the epithelium were noticed in the treated sheep. Histological analysis of the treated group showed no significant differences from the control group. The control group showed similar changes, some less pronounced. The combined treatment of hyperthermia with mitomycin C did not cause major damage to the urinary bladder or adjacent organs. All changes were superficial and reversible, and the control group showed similar changes, some less pronounced. Although this is an experimental model based on one single session treatment, rather than repeated treatments, it suggests that the approach may be useful in future studies both in models and man.