Clinical performance of Xpert Bladder Cancer (BC) Monitor, a mRNA-based urine test, in active surveillance (AS) patients with recurrent non-muscle-invasive bladder cancer (NMIBC): results from the Bladder Cancer Italian Active Surveillance (BIAS) project

How do endoscopic bladder tumor resection techniques affect pathology practice? EAU Section of Uro-Technology (ESUT) and Uropathology (ESUP) survey

PURPOSE

We aimed to examine how different endoscopic bladder tumor resection techniques affect pathologists' clinical practice patterns.

METHODS

An online survey including 28 questions clustered in four main sections was prepared by the ESUT ERBT Working Group and released to the pathologists working in the institutions of experts of the ESUT Board and the working groups and experts in the uropathology working group. A descriptive analysis was performed using the collected data.

RESULTS

Sixty-eight pathologists from 23 countries responded to the survey. 37.3% of the participants stated that they always report the T1 sub-staging. Of those who gave sub-staging, 61.3% used T1a, b. 85.2% think that en bloc samples provide spatial orientation faster than piecemeal samples, and 60% think en bloc samples are timesaving during an inspection. 55.7% stated that whether the tissue sample is en bloc or piecemeal is essential. 57.4% think en bloc sample reduces turnaround time and is cost-effective for 44.1%. A large number of pathologists find that the pathology examination of piecemeal samples has a longer learning curve.

CONCLUSION

The survey shows that pathologists think that they can diagnose faster, accurately, and cost-effectively with ERBT samples, but they do not often encounter them in practice. Moreover, en bloc samples may be a better choice in pathology resident training. Evidence from real-life observational pathology practice and clinical research can reveal the current situation more clearly and increase awareness on proper treatment in endoscopic management of bladder tumors.

Xpert Bladder Cancer Monitor for the Early Detection of Non-Muscle Invasive Bladder Cancer Recurrences: Could Cystoscopy Be Substituted?

XBM was prospectively assessed in spontaneous urine collected just before flexible cystoscopy and washing cytology carried out within the first 2 years follow-up of 337 patients with NMIBC. Recurrences were pathologically confirmed in 49 patients (14.5%), 22 of them being high-risk (6.5%). The XBM sensitivity for detecting any type of recurrence was 69.4% and 63.6% in the cases of high-risk NMIBC. Negative predictive value (NPV) for XBM was 93% for all recurrences and 96.2% for high-risk recurrences. XBM could have avoided 213 invasive controls but missed the detection of 15 recurrences (30.6%)-8 of them of high-risk (36.4%). XBM false positive elevations were detected in 90 patients (26.7%), whereas 10 patients with the invasive method had a false positive result (3%), p <0.001. However, early detection of recurrences during the first year's follow-up after an XBM false positive result was observed in 18 patients (20%). On the other hand, 19 recurrences were detected during this period among the rest of the patients (7.7%)-p = 0.003, and odds ratio (OR) 3.0 (95% CI 1.5-6.0). Regarding one-year follow-up recurrences, 10% were high-risk recurrences in the XBM false positive group and 3.2% in the rest of the patients-p = 0.021, and OR 3.3 (95% CI 1.2-8.9). Additionally, 11.3% of the patients without false positive results developed a recurrence, p = 0.897, for any recurrence, being 10% and 5.2%, respectively, and high-risk and low-risk recurrences, p = 0.506. After searching for the best XBM cutoff for detecting the 38 high-risk initial recurrences and the early high-risk recurrences after a one-year follow-up, a linear discriminant analysis (LDA) of 0.13 could have avoided 11.3% of cystoscopies and bladder wash cytologies, as this cutoff missed only 1 high-risk recurrence (2.6%). More extensive and well-designed studies will confirm if XBM can improve the surveillance of NMIBC.

RNA-based urinary assays for non-muscle invasive bladder cancer

PURPOSE OF REVIEW

To provide an overview of the recent literature on RNA-based molecular urine assays for the diagnosis and surveillance of non-muscle invasive bladder cancer (NMIBC).

RECENT FINDINGS

Articles were eligible for inclusion if performance metrics sensitivity, specificity, and negative-predictive value (NPV) were reported or could be calculated. Only prospective studies published between 2020-2022 were included. Five out of fourteen studies addressed the primary diagnostic setting; the proportion of gross hematuria patients in all study populations was >50%. Only one study reported performance metrics within a microscopic hematuria subgroup. This study evaluated Xpert Bladder and reported a sensitivity: 73%, specificity: 84%, NPV: 99%, and PPV: 12%. Ten studies assessed test performance during surveillance for NMIBC. For the detection of high-grade (HG) and high-risk (HR) NMIBC, sensitivity, specificity, NPV, and PPV varied between 78-100%, 64-89%, 97.0-99.7%, and 9.2-39%.

SUMMARY

Multiple RNA-based urine assays have been investigated for the detection of urothelial cancer in the primary or surveillance setting. However, studies included within this review have important limitations, hampering the interpretation of study results. As such, performance metrics should be interpreted with caution and further research is required to evaluate the clinical impact of RNA-based urine assays in daily practice.

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

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

Distant metastasis without regional progression in non-muscle invasive bladder cancer: case report and pooled analysis of literature

Background

Non-muscle invasive bladder cancer (NMIBC) represents the majority of bladder neoplasms. It is unusual for NMIBC metastasizing distantly without regional progression, namely metastatic NMIBC (mNMIBC), which is still poorly understood and easily omitted based on current management policies. So far, description of mNMIBC is limited to a few case reports.

Methods

We reported a 70-year-old man with NMIBC who suffered from cervical metastasis without pelvic recurrence at 41 months after initial diagnosis. Then we performed a collective analysis of this case together with published mNMIBC cases searched from PubMed, Embase, and Web of Science, aiming to illustrate baseline clinicopathologic parameters, metastatic patterns, and treatment outcomes of these patients and analyze associated influencing factors.

Results

After scrupulous review, 45 cases previous reported and the one from our center were incorporated into the aggregated cohort of mNMIBC, including 34 males and 12 females. Primary tumors from 46.7% of patients were high-grade (HG) or grade 3 (G3) and 65.1% had T1 lesions. Aberrant biomarker expression was found in tumors of some cases. Most (40/46) metastases of mNMIBC occurred at a single site, mainly in lung, bone and lymph nodes. Apart from three cases of de novo mNMIBC, the mean metastasis-free survival (MFS) interval of metachronous mNMIBC was 42.5 months, which was obviously longer than conventional metastatic bladder cancer. Shortened MFS interval was associated with old age, T1 or HG/G3 primary tumors, and non-lung metastases. Systemic chemotherapy and metastasectomy or radiotherapy for oligometastatic lesion were main therapeutic approaches of mNMIBC, and immunotherapy was adopted for the case from our center. Lung and bone metastases correlated with relatively favorable and unfavorable survival outcomes, respectively. Compared with monotherapy, chemotherapy, or immunotherapy combined with local cytoreduction got more favorable outcomes.

Conclusion

Although rare, mNMIBC occurs more in tumors with high-risk features. Usually, mNMIBC metastasizes later than conventional metastatic bladder cancer and manifests as solitary lesion. Outcomes of mNMIBC would be influenced by metastatic site and post-metastatic treatment. Systemic treatment combined with local cytoreduction may render survival benefit in selected patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02664-5.

Xpert Bladder Cancer Monitor May Avoid Cystoscopies in Patients Under "Active Surveillance" for Recurrent Bladder Cancer (BIAS Project): Longitudinal Cohort Study

Objectives

To test the hypothesis that patients under active surveillance (AS) for Non-muscle Invasive Bladder Cancer (NMIBC) who were negative on longitudinal re-testing by the Xpert^® Bladder Cancer Monitor (Xpert BC Monitor) assay may avoid unnecessary cystoscopies and urine cytology (UC).

Subjects/Patients (or Materials) and Methods

This is a prospective cohort study of patients enrolled in the AS protocol for recurrent NMIBC (Bladder Cancer Italian Active Surveillance, BIAS project), whose urine samples were analyzed by Xpert BC Monitor upon entry in the study (T0). Patients who had a negative Xpert test and did not fail AS, underwent additional Xpert tests after 4 (T1), 8 (T2), and 12 (T3) months. The clinical utility of Xpert was assessed by determining the number of cystoscopies and UC that could be avoided within 1 year.

Results

Overall, 139 patients were tested with Xpert at T0. Median follow-up was 23 (IQR 17–27) months. Sixty-eight (48.9%) patients failed AS, 65 (46.7%) are currently on AS, and 6 (4.3%) were lost at follow-up. At T0 57 (41.0%) patients had a negative test and 36 (63.2%) are still in AS. In patients with 2 consecutives negative Xpert tests, we could have avoided 73.9% of unnecessary cystoscopies, missing 26.4% failure, up to avoid all cystoscopies with 4 negative tests missing only 12% of failure. All the patients with negative Xpert had negative UC. Failure-free-survival at median follow-up (23 month) stratified for having 0, 1, or ≥2 negative tests was 67.0, 55.1. and 84.1, respectively.

Conclusion

Our findings suggest that Xpert BC Monitor assay, when it is longitudinally repeated, could significantly reduce the number of unnecessary cystoscopies and UC during their follow-up.

The Role of New Technologies in the Diagnosis and Surveillance of Non-Muscle Invasive Bladder Carcinoma: A Prospective, Double-Blinded, Monocentric Study of the XPERT© Bladder Cancer Monitor and Narrow Band Imaging© Cystoscopy

Simple Summary

Patients with bladder cancer (BC) require close follow-up with white-light cystoscopy (WLC) and cytology. In this study, we sought to assess (a) the performance of a novel cystoscopy technology based on Narrow Band Imaging© (NBI), and (b) a new urine test (XPERT© Bladder Cancer Monitor, XBCM) that detects cancer proteins. We compared these to the established standard follow-up diagnostics. Our study showed that NBI cystoscopy does not provide any additional benefit over standard WLC. However, the XBCM urine test performed particularly well in instances of aggressive high-grade tumor recurrence. Therefore, XBCM may have enhanced utility in the early detection of potentially harmful BC recurrence.

Abstract

Follow-up is essential for the early detection of recurrent non-muscle invasive bladder cancers (NMIBC). This study investigates the clinical relevance of new diagnostic tools such as an mRNA-based urine test (XPERT© Bladder Cancer Monitor, XBCM) and Narrow Band Imaging© (NBI) and compares them with the established follow-up diagnostics (white-light cystoscopy (WLC) and urine cytology). This was a prospective, double-blind, single-center study that involved patients undergoing NMIBC screening at a tertiary care center. Enrollment occurred between January 2018 and March 2020. In addition to standard care (WLC, cytology, and ultrasound), patients underwent XBCM urine testing and NBI cystoscopy. In total, 301 WLCs were performed; through this, 49 patients demonstrated NMIBC recurrence. NBI cystoscopy was congruent with WLC in all patients. Cytology showed a sensitivity (SE) and specificity (SP) of 27% and 97% (PPV: 65%; NPV 87%), respectively, whereas XBCM showed SE and SP of 58% and 89%, respectively (PPV: 51%; NPV: 92%; AUC: 0.79 (0.716–0.871)). Subgroup analysis showed improved SE and similar SP (PPV, NPV) for high grade (HG) recurrence, with a SE of 74% and SP of 89% (39%, 97%). NBI cystoscopy does not necessarily provide additional benefit over standard WLC. However, the XBCM may provide better SE and a diagnostic advantage in instances of HG disease recurrence.

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

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

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.

Diagnostic Accuracy of Novel Urinary Biomarker Tests in Non-muscle-invasive Bladder Cancer: A Systematic Review and Network Meta-analysis

CONTEXT

During the past decade, several urinary biomarker tests (UBTs) for bladder cancer have been developed and made commercially available. However, none of these is recommended by international guidelines so far.

OBJECTIVE

To assess the diagnostic estimates of novel commercially available UBTs for diagnosis and surveillance of non-muscle-invasive bladder cancer (NMIBC) using diagnostic test accuracy (DTA) and network meta-analysis (NMA).

EVIDENCE ACQUISITION

PubMed, Web of Science, and Scopus were searched up to April 2021 to identify studies addressing the diagnostic values of UBTs: Xpert bladder cancer, Adxbladder, Bladder EpiCheck, Uromonitor and Cxbladder Monitor, and Triage and Detect. The primary endpoint was to assess the pooled diagnostic values for disease recurrence in NMIBC patients using a DTA meta-analysis and to compare them with cytology using an NMA. The secondary endpoints were the diagnostic values for high-grade (HG) recurrence as well as for the initial detection of bladder cancer.

EVIDENCE SYNTHESIS

Twenty-one studies, comprising 7330 patients, were included in the quantitative synthesis. In most of the studies, there was an unclear risk of bias. For NMIBC surveillance, novel UBTs demonstrated promising pooled diagnostic values with sensitivities up to 93%, specificities up to 84%, positive predictive values up to 67%, and negative predictive value up to 99%. Pooled estimates for the diagnosis of HG recurrence were similar to those for the diagnosis of any-grade recurrence. The analysis of the number of cystoscopies potentially avoided during the follow-up of 1000 patients showed that UBTs might be efficient in reducing the number of avoidable interventions with up to 740 cystoscopies. The NMA revealed that diagnostic values (except specificity) of the novel UBTs were significantly higher than those of cytology for the detection of NMIBC recurrence. There were too little data on UBTs in the primary diagnosis setting to allow a statistical analysis.

CONCLUSIONS

Our analyses support high diagnostic accuracy of the studied novel UBTs, supporting their utility in the NMIBC surveillance setting. All of these might potentially help prevent unnecessary cystoscopies safely. There are not enough data to reliably assess their use in the primary diagnostic setting. These results have to be confirmed in a larger cohort as well as in head-to-head comparative studies. Nevertheless, our study might help policymakers and stakeholders evaluate the clinical and social impact of the implementation of these tests into daily practice.

PATIENT SUMMARY

Novel urinary biomarker tests outperform cytology with the potential of improving routine clinical practice by preventing unnecessary cystoscopic examinations during the surveillance of non-muscle-invasive bladder cancer.

Xpert bladder cancer monitor in surveillance of bladder cancer: Systematic review and meta-analysis

INTRODUCTION

There is a need for sensitive and specific biomarkers for detecting recurrences in patients with non-muscle invasive bladder cancer (NMIBC) on surveillance. Xpert bladder cancer (BC) monitor is the latest rapid in vitro qualitative test that detects expression of 5 mRNAs using a GeneXpert instrument. The primary aim of this review was to systematically review and pool the data regarding the diagnostic performance of Xpert BC in patients with NMIBC.

METHODS

Systematic literature search using 4 electronic databases (PubMed, EMbase, Scopus and Web of science) was performed. Pooled sensitivity, specificity and diagnostic odds ratio (DOR) were estimated using DerSimonian-Laird random-effects model. Standard Preferred Reporting Items for Systematic reviews and Meta-analysis guidelines were followed and the study protocol was registered with PROSPERO (CRD42021249762).

RESULTS

In this review, 11 prospective studies with 2,896 patients were included. Pooled sensitivity and specificity for Xpert BC were 73% (95% confidence interval (CI) 65%-80%) and 77% (95% CI 69%-84%) respectively. Area under curve (AUC) for Xpert BC monitor was 0.81 (0.78-0.84) respectively. Subgroup analysis from 7 studies for patients with high-grade recurrence revealed sensitivity, specificity and AUC of 0.86 (0.77-0.92), 0.78 (0.75-0.81) and 0.87 (0.84-0.90) respectively. Similar analysis for patients with low-grade recurrence revealed sensitivity, specificity and AUC of 0.58 (0.47-0.68), 0.79 (0.75-0.82) and 0.79 (0.75-0.82) respectively.

CONCLUSION

Xpert BC monitor has overall acceptable diagnostic accuracy. Sensitivity is higher for high-grade disease for detecting recurrences in patients with NMIBC on surveillance.

Prominence of urinary biomarkers for bladder cancer in the COVID-19 era: From the commercially available to new prospective candidates

Molecular markers detected in urine may improve our understanding of the evolution of bladder cancer (BCa) and its micro- and macroenvironment. Detection of such markers will identify disease earlier, allow stratification of patients according to risk, and improve prognostication and prediction of outcomes, thereby facilitating targeted therapy. However, current guidelines have yet to embrace such markers for routine management of BCa, and most research studies have focused on urine-based tumor markers. In this review, we summarize known urinary biomarkers for BCa and highlight newly identified molecules. We then discuss the challenges that must be overcome to incorporate these markers into clinical care.

Long-term Follow-up and Factors Associated with Active Surveillance Failure for Patients with Non-muscle-invasive Bladder Cancer: The Bladder Cancer Italian Active Surveillance (BIAS) Experience

Active surveillance (AS) has been proposed as an alternative to transurethral resection (TUR) in selected patients with recurrent low-risk non-muscle-invasive bladder cancer (NMIBC). Here we report long-term results for patients on AS and investigate features associated with AS failure. Cases with recurrence after diagnosis of low-grade (LG) pTa/pT1a NMIBC were enrolled in the Bladder Italian Active Surveillance (BIAS) project. Over 251 AS events, we observed 130 failures (51.8%). In these patients, final pathology showed 25 benign lesions (19.2%) and 92 LG Ta (70.7%), 12 high-grade Ta/T1 (9.2%), and one T2 (0.7%) tumor. The treatment-free probability at 12, 18, 24, and 36 mo was 59.7%, 54.5%, 46.3%, and 40.4%, respectively. We identified 95 patients (37.8%) who remained on AS for >18 mo. A multivariable Cox regression model confirmed that patients with a history of multiple TURs (hazard ratio [HR] 1.59, 95% confidence interval [CI] 1.01-2.51) and those with more than one lesion at AS entry (HR 1.63, 95% CI 1.05-2.54) were significantly more likely to experience AS failure. Our results confirm that well-selected patients with NMIBC can safely remain on AS for a long period of time. Multiple TURs and multiple lesions at AS enrollment are associated with a higher risk of AS failure. PATIENT SUMMARY: Active surveillance has been proposed as an alternative to surgery for patients with recurrent low-risk superficial bladder cancer. Our report confirms that well-selected patients can safely avoid or postpone surgery.

Assessment of Xpert Bladder Cancer Monitor test performance for the detection of recurrence during non-muscle invasive bladder cancer follow-up

Purpose

To assess the performance of the Xpert Bladder Cancer (BC) Monitor during the follow-up of patients with non-muscle invasive bladder cancer (NMIBC).

Methods

Patients with previously diagnosed NMIBC and followed up in clinical practice settings in two French urology departments between September 2017 and July 2019 were consecutively enrolled in this prospective observational study. Patients with a positive cystoscopy or computed tomography urogram underwent subsequent transurethral resection of the bladder, and/or biopsy, and the specimens were pathologically assessed. Cytology and Xpert BC Monitor tests were performed on urine samples. Xpert BC Monitor performance was assessed versus cystoscopy for disease-negative patients or versus histology for disease-positive patients, and was compared to that of cytology.

Results

Overall, 500 patients with a median age of 70.0 years were included. NMIBC recurrence was diagnosed in 44 cases (8.8%). Overall sensitivity, specificity, and negative predictive values (NPVs) were 72.7% (32/44), 73.7% (330/448) and 96.5% (330/342) for the Xpert BC Monitor, and 7.7% (2/26), 97.8% (310/317) and 92.8% (310/334) for cytology, respectively. The Xpert BC Monitor detected 92.3% (12/13) of the high-grade tumours and ruled out their presence in 99.7% (330/331) of cases. Analysis of the areas under the receiver operating characteristic curves demonstrated the superior performance of the Xpert BC Monitor over that of cytology.

Conclusion

Xpert BC Monitor performance was superior to that of cytology in the follow-up of NMIBC. The exclusion of aggressive tumours with a very high NPV (99.7%) supports the use of this urinary test in daily practice.

Liquid Biopsy Biomarkers in Urine: A Route towards Molecular Diagnosis and Personalized Medicine of Bladder Cancer

Bladder cancer (BC) is characterized by high incidence and recurrence rates together with genomic instability and elevated mutation degree. Currently, cystoscopy combined with cytology is routinely used for diagnosis, prognosis and disease surveillance. Such an approach is often associated with several side effects, discomfort for the patient and high economic burden. Thus, there is an essential demand of non-invasive, sensitive, fast and inexpensive biomarkers for clinical management of BC patients. In this context, liquid biopsy represents a very promising tool that has been widely investigated over the last decade. Liquid biopsy will likely be at the basis of patient selection for precision medicine, both in terms of treatment choice and real-time monitoring of therapeutic effects. Several different urinary biomarkers have been proposed for liquid biopsy in BC, including DNA methylation and mutations, protein-based assays, non-coding RNAs and mRNA signatures. In this review, we summarized the state of the art on different available tests concerning their potential clinical applications for BC detection, prognosis, surveillance and response to therapy.

The performance of the Xpert Bladder Cancer Monitor Test and voided urinary cytology in the follow-up of urinary bladder tumors

Background

Cystoscopy in complement with urinary cytology represents the gold standard for the follow-up of patients with urinary bladder tumours. Xpert Bladder Cancer Monitor Test (XBC) is a novel mRNA-based urine test for bladder cancer surveillance. The aim of the study was to evaluate the performance of the XBC and voided urinary cytology (VUC) in the follow-up of bladder tumours.

Patients and methods

The XBC was performed on stabilized voided urine and VUC was performed on urine samples. The results were compared to cystoscopic findings and histopathological results after transurethral resection of the bladder lesion.

Results

For the prediction of malignant histopathological result sensitivity, the specificity and negative predictive value were 76.9%, 9 7.5% and 93.0% for the XBC and 38.4%, 9 7.5% and 83.3%, respectively for VUC. For the prediction of suspicious or positive cystoscopic finding sensitivity, the specificity and negative predictive value were 75.0%, 95.2%, and 93.0% respectively for the XBC and 41.7%, 97.6%, and 85.4% for VUC. The sensitivities for papilary urothelial neoplasms of low malignant potential (PUNLMP), low- and high-grade tumours were 0.0%, 66.7% an d 100.0% for the XBC and 0.0%, 66 .7% and 42.9%, respectively for VUC.

Conclusions

The XBC showed significantly higher overall sensitivity and negative predictive value than VUC and could be used to increase the recommended follow-up cystoscopy time intervals. Complementing the XBC and voided urinary cytology does not improve performance in comparison to the XBC alone.

A novel ultra-sensitive method for the detection of FGFR3 mutations in urine of bladder cancer patients - Design of the Urodiag® PCR kit for surveillance of patients with non-muscle-invasive bladder cancer (NMIBC)

Background

We have recently developed a highly accurate urine-based test, named Urodiag®, associating FGFR3 mutation and DNA methylation assays for recurrence surveillance in patients with low-, intermediate-, and high-risk NMIBC. Previously, the detection of four FGFR3 mutations (G372C, R248C, S249C and Y375C) required amplification steps and PCR products were analyzed by capillary electrophoresis (Allele Specific-PCR, AS-PCR), which was expensive and time-consuming. Here, we present the development a novel ultra-sensitive multiplex PCR assay as called “Mutated Allele Specific Oligonucleotide-PCR (MASO-PCR)”, generating a cost-effective, simple, fast and clinically applicable assay for the detection of FGFR3 mutations in voided urine.

Methods

Comparative clinical performances of MASO-PCR and AS-PCR technologies were performed from 263 urine DNA samples (87 FGFR3 mutated and 176 FGFR3 wild-type). In the development of Urodiag® PCR Kit, we studied the stability and reproducibility of each all-in-one PCR master mix (single reaction mixture including all the necessary PCR components) for MASO-PCR and QM-MSPCR (Quantitative Multiplex Methylation-Specific PCR to co-amplify SEPTIN9, HS3ST2 and SLIT2 methylated genes) assays.

Results

Complete concordance (100%) was observed between the MASO-PCR and AS-PCR results. Each PCR master mix displayed excellent reproducibility and stability after 12 months of storage at − 20 °C, with intra-assay standard deviations lower than 0.3 Ct and coefficient of variations (CV) lower than 1%. The limit of detection (LoD) of MASO-PCR was 5% mutant detection in a 95% of wild-type background. The limit of quantification (LoQ) of QM-MSPCR was 10 pg of bisulfite-converted DNA.

Conclusions

We developed and clinically validated the MASO-PCR assay, generating cost-effective, simple, fast and clinically applicable assay for the detection of FGFR3 mutations in urine. We also designed the Urodiag® PCR Kit, which includes the MASO-PCR and QM-MSPCR assays. Adapted to routine clinical laboratory (simplicity, accuracy), the kit will be a great help to urologists for recurrence surveillance in patients at low-, intermediate- and high-risk NMIBC. Reducing the number of unnecessary cystoscopies, it will have extremely beneficial effects for patients (painless) and for the healthcare systems (low cost).