Toward noninvasive follow-up of low-risk bladder cancer - Rationale and concept of the UroFollow trial

Simulation of the effects of molecular urine markers in follow-up of patients with high-risk non-muscle invasive bladder cancer

A plethora of urine markers for the management of patients with bladder cancer has been developed and studied in the past. However, the clinical impact of urine testing on patient management remains obscure. The goal of this manuscript is to identify scenarios for the potential use of molecular urine markers in the follow-up of patients with high-risk non-muscle-invasive BC (NMIBC) and estimate potential risks and benefits. Information on the course of disease of patients with high-risk NMIBC and performance data of a point-of-care test (UBC rapid™), an MCM-5 directed ELISA (ADXBLADDER™), and 2 additional novel assays targeting alterations of mRNA expression and DNA methylation (Xpert bladder cancer monitor™, Epicheck™) were retrieved from high-quality trials and/or meta-analyses. In addition, the sensitivity of white light cystoscopy (WLC) and the impact of a urine marker result on the performance of WLC were estimated based on fluorescence cystoscopy data and information from the CeFub trial. This information was applied to different scenarios in patient follow-up and sensitivity, estimated number of cystoscopies, and the numbers needed to diagnose were calculated. The sensitivity of guideline-based regular follow-up (SOC) at 1 year was calculated at 96%. For different marker-supported strategies sensitivities ranging from 77% to 97.9% were estimated. Calculations suggest that several strategies are effective for the SOC. While for the SOC 24.6 WLCs were required to diagnose 1 tumor recurrence (NND), this NND dropped below 5 in some marker-supported strategies. Based on the results of this simulation, a marker-supported follow-up of patients with HR NMIBC is safe and offers the option to significantly reduce the number of WLCs. Further research focusing on prospective randomized trials is needed to finally find a way to implement urine markers into clinical decision-making.

Clinical Trial Protocol for "Replace Cysto": Replacing Invasive Cystoscopy with Urine Testing for Non-muscle-invasive Bladder Cancer Surveillance-A Multicenter, Randomized, Phase 2 Healthcare Delivery Trial Comparing Quality of Life During Cancer Surveillance with Xpert Bladder Cancer Monitor or Bladder EpiCheck Urine Testing Versus Frequent Cystoscopy

"Replace Cysto" is a multisite randomized phase 2 trial including 240 participants with low-grade intermediate-risk non-muscle-invasive bladder cancer, in which participants will be randomized 1:1:1 to one of two urine marker-based approaches alternating a urine marker test (Xpert Bladder Cancer Monitor or Bladder EpiCheck) with cystoscopy or to frequent scheduled cystoscopy. The primary objective is to determine whether urinary quality of life after surveillance is significantly improved in the urine marker arms. The primary outcome will be the patient-reported urinary quality of life domain score of the validated QLQ-NMIBC24 instrument, measured 1-3 d after surveillance. Exploratory outcomes include discomfort after surveillance, the number of invasive procedures that participants undergo per 1000 person years, complications from these procedures per 1000 person years, nonurinary quality of life, acceptability of surveillance, and bladder cancer recurrence and progression. Comparators include surveillance using (1) the Xpert Bladder Cancer Monitor test, (2) the Bladder EpiCheck urinary marker, or (3) frequent cystoscopy alone. After a negative cystoscopy ≤4 mo following bladder tumor resection, all the participants will undergo surveillance at 6, 12, 18, and 24 mo (with time zero defined as the date of the most recent bladder tumor resection). In the urine marker arms, surveillance at 6 and 18 mo will be performed with the marker. Regardless of the arm, participants will undergo cystoscopy at 12 and 24 mo. End of study for each participant will be their 24-mo cystoscopy. Overall trial duration is estimated at 5 yr from when the study opens to enrollment until completion of data analyses. The trial is registered at clinicaltrials.gov (NCT05796375).

Long-term Recurrence Rates of Low-risk Non-muscle-invasive Bladder Cancer-How Long Is Cystoscopic Surveillance Necessary?

BACKGROUND

While low-risk non-muscle-invasive bladder cancer (LR-NMIBC) has a low propensity to progress, the risk of recurrence remains high (50% within 4 yr). Guidelines recommend cystoscopic surveillance after resection, but the necessary duration of follow-up is debated.

OBJECTIVE

To determine the risk of recurrence beyond 5 yr after diagnosis in patients with LR-NMIBC, and to identify risk factors of recurrence.

DESIGN, SETTING, AND PARTICIPANTS

In this multicenter retrospective observational study, patients who received their first transurethral bladder tumor resection before 2016 for LR-NMIBC were included. Low risk was defined as a primary, solitary, low grade, Ta bladder tumor measuring <3 cm.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was determination of the recurrence rates at 1, 2, and 5 yr. The secondary endpoints included overall recurrence-free survival (RFS) and high-risk RFS. A univariate analysis and multivariable logistic regression were performed to assess the risk factors for recurrence over the study period.

RESULTS AND LIMITATIONS

The median age of the 577 patients was 70.9 yr, and 126 (21.8%) patients were female. The median follow-up was 69.6 (interquartile range: 58.4) mo, and recurrence was observed in 236 (40.9%) patients. The 1-, 2-, and 5-yr RFS rates were 81.6% (95% confidence interval 78.4-84.9), 72.4% (68.7-76.3), and 59.2% (55-63.8), respectively. Recurrence after 5 yr was observed in 13.1% (28/213). High-risk recurrence, defined as the first recurrence of a high-grade and/or ≥T1 tumor, occurred in 6.2% (36/579) overall and 2.8% (6/213) after 5 yr. The lack of a single postoperative dose of chemotherapy and tumor size >2 cm were prognostic factors of recurrence.

CONCLUSIONS

The risk of recurrence in patients with LR-NMIBC decreases progressively after the 1st year and remains low beyond 5 yr. Discontinuation of endoscopic surveillance after 5 yr in patients with LR-NMIBC can be discussed. Treatment with postoperative chemotherapy and tumor size <2 cm may be relevant variables to identify patients who will benefit from cystoscopic follow-up as short as 12 mo.

PATIENT SUMMARY

In this study, we observed that 13% of patients who did not have a recurrence during the first 5 yr following the diagnosis of low-risk non-muscle-invasive bladder cancer will recur after this time point. Discontinuation of cystoscopic surveillance can be discussed after 5 yr in these patients.

Urine biomarkers in bladder cancer - current status and future perspectives

Urine markers to detect bladder cancer have been the subject of research for decades. The idea that urine - being in continuous contact with tumour tissue - should provide a vector of tumour information remains an attractive concept. Research on this topic has resulted in a complex landscape of many different urine markers with varying degrees of clinical validation. These markers range from cell-based assays to proteins, transcriptomic markers and genomic signatures, with a clear trend towards multiplex assays. Unfortunately, the number of different urine markers and the efforts in research and development of clinical grade assays are not reflected in the use of these markers in clinical practice, which is currently limited. Numerous prospective trials are in progress with the aim of increasing the quality of evidence about urinary biomarkers in bladder cancer to achieve guideline implementation. The current research landscape suggests a division of testing approaches. Some efforts are directed towards addressing the limitations of current assays to improve the performance of urine markers for a straightforward detection of bladder cancer. Additionally, comprehensive genetic analyses are emerging based on advances in next-generation sequencing and are expected to substantially affect the potential application of urine markers in bladder cancer.

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.

Considering the Effects of Modern Point-of-Care Urine Biomarker Assays in Follow-Up of Patients with High-Risk Non-muscle-Invasive Bladder Cancer

BACKGROUND

Although a plethora of urine markers for diagnosis and follow-up of patients with bladder cancer (BC) has been developed and studied, the clinical impact of urine testing on patient management remains unclear. The goal of this manuscript is to identify scenarios for a potential use of modern point-of-care (POC) urine marker assays in the follow-up of patients with high-risk non-muscle-invasive BC (NMIBC) and estimate potential risks and benefits.

METHODS

To permit comparison between different assays, the results of 5 different POC assays studied in a recent prospective multicenter study including 127 patients with suspicious cystoscopy undergoing TURB were used for this simulation. For the current standard of care (SOC), a "marker-enforced" procedure, and a combined strategy sensitivity (Se), estimated number of cystoscopies, and the numbers needed to diagnose (NND) over a 1-year follow-up period were calculated.

RESULTS

For regular cystoscopy (SOC), a Se of 91.7% and a NND of 42.2 repetitive office cystoscopies (WLCs) for 1 recurrent tumor at 1 year were calculated. For the "marker-enforced" strategy, marker sensitivities between 94.7% and 97.1% were observed. The "combined" strategy yielded for markers with a Se exceeding 50% an overall Se at 1 year similar or superior to the current SOC. Savings regarding the number of cystoscopies in the "marker-enforced" strategy vs. the SOC were small, while, depending on the marker, up to 45% of all cystoscopies may be saved using the "combined" strategy.

CONCLUSIONS

Based on the results of this simulation, a marker-supported follow-up of patients with high-risk (HR) NMIBC is safe and offers options to significantly reduce the number of cystoscopies without compromising the Se. Further research focusing on prospective randomized trials is needed to finally find a way to include marker results into clinical decision-making.

Reducing the Frequency of Follow-up Cystoscopy in Low-grade pTa Non-muscle-invasive Bladder Cancer Using the ADXBLADDER Biomarker

BACKGROUND

Non-muscle-invasive bladder cancer (NMIBC) is one of the most expensive cancers owing to frequent follow-up cystoscopies for detection of recurrence.

OBJECTIVE

To assess if the noninvasive ADXBLADDER urine test could permit a less intensive surveillance schedule for patients with low-grade (LG) pTa tumor without carcinoma in situ (CIS) at the previous diagnosis.

DESIGN, SETTING, AND PARTICIPANTS

In a prospective, double-blind, multicenter study, 629 patients underwent follow-up cystoscopy, transurethral resection of bladder tumor/biopsy of suspect lesions, and ADXBLADDER testing.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Diagnostic test accuracy and decision curve analysis were used to evaluate the impact of ADXBLADDER on decision-making on whether to perform follow-up cystoscopy. The primary endpoint was the negative predictive value (NPV) of ADXBLADDER for detection of high-grade and/or CIS (HG/CIS) recurrence and its impact on reducing unnecessary cystoscopies.

RESULTS AND LIMITATIONS

ADXBLADDER had sensitivity of 66.7% (95% confidence interval [CI] 34.9-90.1%) and an NPV of 99.15% (95% CI 97.8-99.8%) for detection of HG/CIS recurrence. The probability of HG/CIS recurrence was 5.0% for ADXBLADDER-positive patients and 0.85% for ADXBLADDER-negative patients. For HG/CIS recurrence threshold probabilities between 0.85% and 5.0%, ADXBLADDER yields a net benefit with omission of cystoscopy for ADXBLADDER-negative patients. The corresponding net reduction in unnecessary cystoscopies ranges from 11 to 62 per 100 patients.

CONCLUSIONS

Patients with LG pTa tumor at the previous diagnosis, for which the risk of HG/CIS recurrence is low and the ADXBLADDER NPV for ruling out HG/CIS recurrence is 99.15%, are ideally suited for a less intensive, personalized follow-up surveillance strategy using ADXBLADDER, with omission of cystoscopy for ADXBLADDER-negative patients.

PATIENT SUMMARY

ADXBLADDER is a urine test that can predict the probability of recurrence of bladder cancer. Patients diagnosed with low-grade cancer confined to the bladder mucosa are ideally suited for less intensive follow-up using this test, which could reduce unnecessary cystoscopy procedures for those with a negative result, potentially improve quality of life, and reduce overall health care costs.

Exploring solid-phase proximity ligation assay for survivin detection in urine

Urine-based biomarkers are a rational and promising approach for the detection of bladder cancer due to the proximity of urine to the location of the tumor site and the non-invasive nature of its sampling. A well-known and highly investigated biomarker for bladder cancer is survivin. For detection of very small amounts of urinary survivin protein a highly sensitive assay was developed. The assay is based on the immuno-PCR technology, more precisely a solid-phase proximity ligation assay (spPLA). The limit of detection for the survivin spPLA was 1.45 pg/mL, resulting in an improvement of the limit of detection by a factor of approximately 23 compared to the previously in-house developed survivin ELISA. A key step in development was the initial isolation of survivin by a molecular fishing rod based on magnetic beads. Interfering matrix compounds pose a special challenge for further analytical application, but can be overcome by this isolation step. The assay is designed to work with only 500 μL of voided urine. The survivin spPLA showed a sensitivity of 30% and specificity of 89% for bladder cancer detection in this study of 110 bladder cancer cases and 133 clinical controls. Moreover, the results demonstrated again that survivin is a useful complementary marker in combination with UBC^® Rapid by increasing the overall sensitivity to 70% with a specificity of 86%. Although the performance for detection of bladder cancer was rather low, the herein developed assay might serve as a new tool for survivin biomarker research in diverse human fluids, even if the biological matrix is complex or survivin is only present in small amounts.

The Development of Non-Invasive Diagnostic Tools in Bladder Cancer

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

Optimal intervals for follow-up cystoscopy in non-muscle invasive bladder cancer: a systematic review regarding oncological safety

CONTEXT

Improving efficiency of follow-up for non-muscle invasive bladder tumours (NMIBC) without risking disease progression through delays of recurrence diagnosis, is a highly relevant field of research.

OBJECTIVE

The aim of our systematic review was to investigate whether the available evidence support alternative follow-up cytoscopic schedules with respect to oncological safety, compared to those currently given in clinical guidelines for NMIBC. Evidence acquisition we included prospective studies investigating cystoscopy based follow-up schedules including, but not restricted to, comparison of two or more different follow-up schedules with respect to oncological safety measured by recurrence free survival, progression free survival, and overall survival. We allowed for supplementation of modalities such as urinary biomarkers. We screened 680 studies identified by a systematic literature search and, based on our inclusion and exclusion criteria, we included three studies for the narrative synthesis of evidence.

CONCLUSION

In our systematic search of the literature, we found only low level evidence to support current or alternative cystoscopic follow-up schedules. Clinical trials directly aimed at investigating novel follow-up schedules for NMIBC are needed before substantial changes to existing clinical guidelines can be made.

[Rational follow-up of non-muscle invasive bladder cancer]

BACKGROUND

Follow-up for non-muscle invasive bladder cancer (NMIBC) is a challenge for urologists that has not been finally resolved. The intensity of follow-up is based on the recurrence and progression behavior of the tumor as well as the patient's individual situation.

MATERIALS AND METHODS

The following article focuses on the current data situation, the valid German S3 guideline and the available instruments for the detection of relapses and progression, taking into account tumor stages and degree of malignancy.

RESULTS

Urethrocystoscopy, imaging and urine cytology are generally recommended, but the recommendations appear to be too extensive in the case of so-called intermediate risk profiles. Depending on the situation, urine markers could optimize follow-up, although results from prospective randomized studies are still pending.

CONCLUSIONS

The current follow-up of NMIBC is invasive, carries the risk of side effects and increases costs. In the absence of scientific evidence, recommendations for follow-up for NMIBC are naturally based on expert opinion. In the opinion of the authors, overdiagnosis is currently taking place particularly in patients with an intermediate risk profile. The first prospective, marker-based studies are ongoing and will be helpful in the near future to improve the data situation relevant to urological practice.

Biomarkers in Bladder Cancer Surveillance

Aim: This is a narrative review with an aim to summarise and describe urinary biomarkers in the surveillance of non-muscle-invasive bladder cancer (NMIBC). It provides a summary of FDA-approved protein biomarkers along with emerging ones which utilise genetic, epigenetic and exosomal markers. We discuss the current limitations of the available assays. Background: Current guidelines advice a combination of cystoscopy, imaging,and urine cytology in diagnosis and surveillance. Although cytology has a high specificity, it is limited by low sensitivity particularly in low grade tumours. There are six FDA-approved urinary assays for diagnosis and surveillance of bladder cancer. They have shown to improve sensitivity and specificity to be used alongside cytology and cystoscopy but have a lower specificity in comparison to cytology and false positives often occur in benign conditions. Recent developments in laboratory techniques has allowed for use of markers which are RNA-, DNA-based as well as extracellular vesicles in the past decade. Methods: Using the PubMed/Medline search engines as well as Google Scholar, we performed an online search using the terms "bladder cancer," "non-muscle invasive bladder cancer," and "urine biomarkers" with filter for articles in English published up to May 2021. Systematic reviews and original data of clinical trials or observational studies which contributed to the development of the biomarkers were collated. Results: Biomarkers identified were divided into FDA-approved molecular biomarkers, protein biomarkers and gene-related biomarker with a table summarising the findings of each marker with the most relevant studies. The studies conducted were mainly retrospective. Due to the early stages of development, only a few prospective studies have been done for more recently developed biomarkers and limited meta-analyses are available.Therefore a detailed evaluation of these markers are still required to decide on their clinical use. Conclusion: Advancements of analytical methods in BC has driven the research towards non-invasive liquid-based biomarkers in adjunct to urine cytology. Further large prospective studies are required to determine its feasibility in a clinical setting as they are not effective when used in isolation as they have their limitation. With the ongoing pandemic, other than reduction in costs and increased accuracy, the need for biomarkers to cope with delay in cystoscopies in diagnosis and surveillance is crucial. Thus clinical trials with direct comparison is required to improve patient care.

Alternating Cystoscopy with Bladder EpiCheck® in the Surveillance of Low-Grade Intermediate-Risk NMIBC: A Cost Comparison Model

BACKGROUND

Bladder cancer surveillance is invasive, intensive and costly. Patients with low grade intermediate risk non-muscle invasive bladder cancer (NMIBC) are at high risk of recurrence.

OBJECTIVE

The objective of this model is to compare the cost of a strategy to alternate surveillance with cystoscopy and a urine marker, Bladder EpiCheck, to standard surveillance.

METHODS

A decision tree model was built using TreeAge Pro Healthcare to compare standard surveillance (Standard) with a modified surveillance incorporating Bladder EpiCheck. The model was based on 2 years of surveillance. Outcomes were obtained from literature. Costs were obtained from US and 9 European countries. Sensitivity analyses were performed.

RESULTS

The efficacy of the model was equivalent in terms of recurrence for each arm with median recurrence rate of 22%. When setting marker price at 200 local currency, the marker arm was less expensive in the USA, Netherlands, Switzerland, Belgium, Italy, Austria and UK by 154€ to 329£ per patient, for a 2-year period. Cost was higher in France, Spain, and Germany by 33-103€. Cost parity was achieved with marker price between 148€ and $421. Marker cost and specificity have the greatest impact on the overall model cost.

CONCLUSIONS

A strategy alternating the urine marker Bladder EpiCheck with cystoscopy in the surveillance of patients with low grade intermediate risk bladder cancer is cost equivalent in the US and European countries when the marker is priced 148€ -$421, as a result of the marker's high specificity (86%). Prospective studies will be necessary to validate these findings.

UroVysion fluorescence in situ hybridization in urothelial carcinoma: a narrative review and future perspectives

The number of patients with urothelial carcinoma (UC) is high, with a corresponding demand for detecting UC easily and non-invasively. Cystoscopy and urine cytology, with widely known diagnostic accuracies, are the gold standards for identifying UC originating from the bladder. However, cystoscopy or other tests, such as ureteroscopy or retrograde pyelography, are uncomfortable for patients. Tests for urinary biomarkers are expected to satisfy the demand for less invasive tests that will benefit patients with anxiety for invasive tests such as cystoscopy or ureteroscopy. Although several urinary biomarkers have been reported to support the diagnosis or follow-up of UC, their use in the clinic is uncommon. The UroVysion test examines urinary biomarkers using a multitarget, multicolor fluorescence in situ hybridization (FISH) assay. The test uses exfoliated cells found in urine and is a mixture of centromeric fluorescent denatured chromosome enumeration probes for chromosomes 3, 7, and 17 (labelled stratum red, spectrum green and spectrum aqua, respectively), and a locus-specific identifier probe for 9p21 (spectrum gold). It is used for the initial diagnosis of patients with hematuria or the monitoring of patients previously diagnosed with bladder cancer. Almost 20 years have passed since UroVysion was approved by the U.S. Food and Drug Administration, and so this is a well-established test. However, room exists for further research, with numerous reports on this test having been recently published. In order to update our knowledge, we herein present a brief overview of UroVysion and its features that follows the latest findings as they relate to UC.

Urinary biomarkers in bladder cancer: A review of the current landscape and future directions

AIM

This narrative review aims to describe established and emerging urinary biomarkers in the diagnosis and surveillance of non-muscle invasive bladder cancer. It provides a comprehensive account of classical, FDA-approved protein biomarkers and discusses their limitations. Further, we discuss the role that epigenetic, genetic, and exosomal markers can play to enhance sensitivity and specificity of the available tests.

BACKGROUND

The initial diagnosis and surveillance of bladder cancer involves a combination of cystoscopy, upper urinary tract imaging, and urine cytology. Despite high specificity, cytology is limited by low sensitivity. There are currently 6 urinary assays approved by the FDA to enhance diagnosis and surveillance of bladder cancer. While these have improved diagnosis and surveillance when combined with cytology, these tests are still not sufficiently sensitive and false positives often occur in benign conditions which result in inflammation of the urinary tract. Advancements in laboratory techniques have produced significant advancements in epigenetic and genetic markers, as well as extracellular vesicles, with DNA- and RNA-based markers dominating the research in this area in recent years.

METHODS

We identified relevant published data, using the PubMed/ Medline search engines as well as Google Scholar. We performed an online search using the terms "bladder cancer", "non-muscle invasive bladder cancer" in combination with "urine biomarkers" and limited articles in English published up to February 2020. This review consolidated on all available narrative and systematic reviews published in the 5 years in this field, while also reviewing the original data of each clinical trial or observational study which led to the development of the biomarkers.

CONCLUSION

The development of laboratory techniques and understanding urine-based biomarkers in BC has fuelled the use of noninvasive liquid-based biomarkers to complement urine cytology. Nonetheless, none are sufficiently effective when used in isolation, and cytology remains the gold standard in many practices. Future efforts will be focused on using these markers in combination as a predictive signature, and moving on to validating them for use in everyday clinical practice.