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

Improving detection of carcinoma in situ in bladder cancer: urinary cytology vs the Xpert® BC Monitor

OBJECTIVE

To investigate and compare the performance of urinary cytology and the Xpert BC Monitor test in the detection of bladder cancer in various clinically significant patient cohorts, including patients with carcinoma in situ (CIS), in a prospective multicentre setting, aiming to identify potential applications in clinical practice.

PATIENTS AND METHODS

A total of 756 patients scheduled for transurethral resection of bladder tumour (TURBT) were prospectively screened between July 2018 and December 2020 at six German University Centres. Central urinary cytology and Xpert BC Monitor tests were performed prior to TURBT. The diagnostic performance of urinary cytology and the Xpert BC Monitor was evaluated according to sensitivity (SN), specificity (SC), negative predictive value (NPV) and positive predictive value (PPV). Statistical comparison of urinary cytology and the Xpert BC Monitor was conducted using the McNemar test.

RESULTS

Of 756 screened patients, 733 (568 male [78%]; median [interquartile range] age 72 [62-79] years) were included. Bladder cancer was present in 482 patients (65.8%) with 258 (53.5%) high-grade tumours. Overall SN, SC, NPV and PPV were 39%, 93%, 44% and 92% for urinary cytology, and 75%, 69%, 59% and 82% for the Xpert BC Monitor. In patients with CIS (concomitant or solitary), SN, SC, NPV and PPV were 59%, 93%, 87% and 50% for urinary cytology, and 90%, 69%, 95% and 50% for the Xpert BC Monitor. The Xpert BC Monitor missed four tumours (NPV = 98%) in patients with solitary CIS, while potentially avoiding 63.3% of TURBTs in inconclusive or negative cystoscopy and a negative Xpert result.

CONCLUSION

Positive urinary cytology may indicate bladder cancer and should be taken seriously. The Xpert BC Monitor may represent a useful diagnostic tool for correctly identifying patients with solitary CIS and unsuspicious or inconclusive cystoscopy.

Diagnostic Test Accuracy of Urinary DNA Methylation-based Biomarkers for the Detection of Primary and Recurrent Bladder Cancer: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

Diagnosis of primary and relapsed bladder carcinomas is accomplished by urethrocystoscopy, an invasive procedure, combined with urinary cytology, with limited sensitivity, resulting in a substantial burden. Thus, noninvasive biomarkers have been investigated, among which DNA methylation has shown promise. This systematic review and meta-analysis sought to assess the diagnostic accuracy of DNA methylation biomarkers reported in the literature for bladder cancer detection, pinpointing the most informative one.

METHODS

The search for this systematic review and meta-analysis was conducted on PubMed, Scopus, and Cochrane Library for relevant studies published until December 31, 2022. A meta-analysis was performed using a random-effect model, to compute the pooled sensitivity and specificity of the markers. PROSPERO's registration ID for the study is CRD42023397703.

KEY FINDINGS AND LIMITATIONS

Out of the 2297 studies retrieved, 68 were included in the final analysis, despite considerable heterogeneity. These involved 12 696 participants, of whom 5557 were diagnosed with bladder cancer. Using diagnostic odds ratio (DOR) as a comparative measure, the five most promising markers (pooled sensitivity, specificity, and DOR) were SALL3 (61%, 97%, and 55.67, respectively), PENK (77%, 93%, and 47.90, respectively), ZNF154 (87%, 90%, and 45.07, respectively), VIM (82%, 90%, and 44.81, respectively), and POU4F2 (81%, 89%, and 34.89, respectively). Urinary cytology identified bladder cancer with 55% sensitivity, 92% specificity, and 14.37 DOR.

CONCLUSIONS AND CLINICAL IMPLICATIONS

DNA methylation biomarkers disclose high accuracy for bladder cancer detection in urine. Nonetheless, validation studies in different clinical settings are scarce, hampering clinical use. The identified biomarkers should be prioritized in future validation studies.

PATIENT SUMMARY

In this meta-analysis, we include previously published studies that used urine samples of bladder cancer patients' from all around the globe. We were able to compare the diagnostic accuracy of noninvasive markers across different populations. We were able to conclude on the most promising DNA methylation markers to detect bladder cancer using urine.

Urine-Based Biomarker Test Uromonitor® in the Detection and Disease Monitoring of Non-Muscle-Invasive Bladder Cancer-A Systematic Review and Meta-Analysis of Diagnostic Test Performance

Optimal urine-based diagnostic tests (UBDT) minimize unnecessary follow-up cystoscopies in patients with non-muscle-invasive bladder-cancer (NMIBC), while accurately detecting high-grade bladder-cancer without false-negative results. Such UBDTs have not been comprehensively described upon a broad, validated dataset, resulting in cautious guideline recommendations. Uromonitor®, a urine-based DNA-assay detecting hotspot alterations in TERT, FGFR3, and KRAS, shows promising initial results. However, a systematic review merging all available data is lacking. Studies investigating the diagnostic performance of Uromonitor® in NMIBC until November 2023 were identified in PubMed, Embase, Web-of-Science, Cochrane, Scopus, and medRxiv databases. Within aggregated analyses, test performance and area under the curve/AUC were calculated. This project fully implemented the PRISMA statement. Four qualifying studies comprised a total of 1190 urinary tests (bladder-cancer prevalence: 14.9%). Based on comprehensive analyses, sensitivity, specificity, positive-predictive value/PPV, negative-predictive value/NPV, and test accuracy of Uromonitor® were 80.2%, 96.9%, 82.1%, 96.6%, and 94.5%, respectively, with an AUC of 0.886 (95%-CI: 0.851-0.921). In a meta-analysis of two studies comparing test performance with urinary cytology, Uromonitor® significantly outperformed urinary cytology in sensitivity, PPV, and test accuracy, while no significant differences were observed for specificity and NPV. This systematic review supports the use of Uromonitor® considering its favorable diagnostic performance. In a cohort of 1000 patients with a bladder-cancer prevalence of ~15%, this UBDT would avert 825 unnecessary cystoscopies (true-negatives) while missing 30 bladder-cancer cases (false-negatives). Due to currently limited aggregated data from only four studies with heterogeneous quality, confirmatory studies are needed.

Development and validation of a predictive model for the diagnosis of bladder tumors using narrow band imaging

PURPOSE

At present, the prediction of bladder tumor nature during cystoscopy is partially dependent on the clinician's own experience. Subjective factors may lead to excessive biopsy or delayed treatment. The purpose of our study is to establish a reliable model for predicting the nature of bladder tumors using narrow band imaging.

METHODS

From November 2021 to November 2022, the clinical data of 231 patients who required a cystoscopy were prospectively collected at our center. Cystoscopy was performed in 219 eligible patients, in which both tumor and vascular morphology characteristics were recorded. Pathological results were used as the diagnostic standard. A logistic regression analysis was used to screen out factors related to tumor pathology. Bootstrap resampling was used for internal validation. A total of 71 patients from four other centers served as an external validation cohort.

RESULTS

The following diagnostic factors were identified: tumor morphology (cauliflower-like or algae-like lesions), vascular morphology (dotted or circumferential vessels), tumor boundary (clear or unclear), and patients' symptoms (gross hematuria) and were included in the prediction model. The internal validation results showed that the area under the curve was 0.94 (95% CI 0.92-0.97), and the P value from the goodness-of-fit test was 0.97. After external validation, the results showed the area under the curve was 0.89 (95% CI 0.82-0.97) and the P value of the goodness-of-fit test was 0.24.

CONCLUSION

A diagnostic prediction nomogram was established for bladder cancer. The verification results showed that the prediction model has good prediction performance.

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.

A Liquid Biopsy in Bladder Cancer—The Current Landscape in Urinary Biomarkers

The non-muscle invasive bladder cancer tends to recur and progress. Therefore, it requires frequent follow-ups, generating costs and making it one of the most expensive neoplasms. Considering the expensive and invasive character of the current gold-standard diagnostic procedure, white-light cystoscopy, efforts to find an alternative method are ongoing. Although the last decade has seen significant advancements in urinary biomarker tests (UBTs) for bladder cancer, international guidelines have not recommended them. Currently, the paramount urgency is to find and validate the test with the best specificity and sensitivity, which would allow for the optimizing of diagnosis, prognosis, and a treatment plan. This review aims to summarise the up-to-date state of knowledge relating to UBTs and new developments in the detection, prognosis, and surveillance of bladder cancer and their potential applications in clinical practice.

Advances in Diagnosis and Therapy for Bladder Cancer

Bladder cancer (BCa) is one of the most common and expensive urinary system malignancies for its high recurrence and progression rate. In recent years, immense amounts of studies have been carried out to bring a more comprehensive cognition and numerous promising clinic approaches for BCa therapy. The development of innovative enhanced cystoscopy techniques (optical techniques, imaging systems) and tumor biomarkers-based non-invasive urine screening (DNA methylation-based urine test) would dramatically improve the accuracy of tumor detection, reducing the risk of recurrence and progression of BCa. Moreover, intravesical instillation and systemic therapeutic strategies (cocktail therapy, immunotherapy, vaccine therapy, targeted therapy) also provide plentiful measures to break the predicament of BCa. Several exploratory clinical studies, including novel surgical approaches, pharmaceutical compositions, and bladder preservation techniques, emerged continually, which are supposed to be promising candidates for BCa clinical treatment. Here, recent advances and prospects of diagnosis, intravesical or systemic treatment, and novel drug delivery systems for BCa therapy are reviewed in this paper.

Molecular Oncology of Bladder Cancer from Inception to Modern Perspective

Within the last forty years, seminal contributions have been made in the areas of bladder cancer (BC) biology, driver genes, molecular profiling, biomarkers, and therapeutic targets for improving personalized patient care. This overview includes seminal discoveries and advances in the molecular oncology of BC. Starting with the concept of divergent molecular pathways for the development of low- and high-grade bladder tumors, field cancerization versus clonality of bladder tumors, cancer driver genes/mutations, genetic polymorphisms, and bacillus Calmette-Guérin (BCG) as an early form of immunotherapy are some of the conceptual contributions towards improving patient care. Although beginning with a promise of predicting prognosis and individualizing treatments, "-omic" approaches and molecular subtypes have revealed the importance of BC stem cells, lineage plasticity, and intra-tumor heterogeneity as the next frontiers for realizing individualized patient care. Along with urine as the optimal non-invasive liquid biopsy, BC is at the forefront of the biomarker field. If the goal is to reduce the number of cystoscopies but not to replace them for monitoring recurrence and asymptomatic microscopic hematuria, a BC marker may reach clinical acceptance. As advances in the molecular oncology of BC continue, the next twenty-five years should significantly advance personalized care for BC patients.