Role of Restaging Transurethral Resection for T1 Non–muscle invasive Bladder Cancer: A Systematic Review and Meta-analysis

Deep Learning Algorithms for Bladder Cancer Segmentation on Multi-Parametric MRI

BACKGROUND

Bladder cancer (BC) segmentation on MRI images is the first step to determining the presence of muscular invasion. This study aimed to assess the tumor segmentation performance of three deep learning (DL) models on multi-parametric MRI (mp-MRI) images.

METHODS

We studied 53 patients with bladder cancer. Bladder tumors were segmented on each slice of T2-weighted (T2WI), diffusion-weighted imaging/apparent diffusion coefficient (DWI/ADC), and T1-weighted contrast-enhanced (T1WI) images acquired at a 3Tesla MRI scanner. We trained Unet, MAnet, and PSPnet using three loss functions: cross-entropy (CE), dice similarity coefficient loss (DSC), and focal loss (FL). We evaluated the model performances using DSC, Hausdorff distance (HD), and expected calibration error (ECE).

RESULTS

The MAnet algorithm with the CE+DSC loss function gave the highest DSC values on the ADC, T2WI, and T1WI images. PSPnet with CE+DSC obtained the smallest HDs on the ADC, T2WI, and T1WI images. The segmentation accuracy overall was better on the ADC and T1WI than on the T2WI. The ECEs were the smallest for PSPnet with FL on the ADC images, while they were the smallest for MAnet with CE+DSC on the T2WI and T1WI.

CONCLUSIONS

Compared to Unet, MAnet and PSPnet with a hybrid CE+DSC loss function displayed better performances in BC segmentation depending on the choice of the evaluation metric.

Development and validation of an artificial intelligence-based model for detecting urothelial carcinoma using urine cytology images: a multicentre, diagnostic study with prospective validation

Background

Urine cytology is an important non-invasive examination for urothelial carcinoma (UC) diagnosis and follow-up. We aimed to explore whether artificial intelligence (AI) can enhance the sensitivity of urine cytology and help avoid unnecessary endoscopy.

Methods

In this multicentre diagnostic study, consecutive patients who underwent liquid-based urine cytology examinations at four hospitals in China were included for model development and validation. Patients who declined surgery and lacked associated histopathology results, those diagnosed with rare subtype tumours of the urinary tract, or had low-quality images were excluded from the study. All liquid-based cytology slides were scanned into whole-slide images (WSIs) at 40 × magnification and the WSI-labels were derived from the corresponding histopathology results. The Precision Urine Cytology AI Solution (PUCAS) was composed of three distinct stages (patch extraction, features extraction, and classification diagnosis) and was trained to identify important WSI features associated with UC diagnosis. The diagnostic sensitivity was mainly used to validate the performance of PUCAS in retrospective and prospective validation cohorts. This study is registered with the ChiCTR, ChiCTR2300073192.

Findings

Between January 1, 2018 and October 31, 2022, 2641 patients were retrospectively recruited in the training cohort, and 2335 in retrospective validation cohorts; 400 eligible patients were enrolled in the prospective validation cohort between July 7, 2023 and September 15, 2023. The sensitivity of PUCAS ranged from 0.922 (95% CI: 0.811-0.978) to 1.000 (0.782-1.000) in retrospective validation cohorts, and was 0.896 (0.837-0.939) in prospective validation cohort. The PUCAS model also exhibited a good performance in detecting malignancy within atypical urothelial cells cases, with a sensitivity of over 0.84. In the recurrence detection scenario, PUCAS could reduce 57.5% of endoscopy use with a negative predictive value of 96.4%.

Interpretation

PUCAS may help to improve the sensitivity of urine cytology, reduce misdiagnoses of UC, avoid unnecessary endoscopy, and reduce the clinical burden in resource-limited areas. The further validation in other countries is needed.

Funding

National Natural Science Foundation of China; Key Program of the National Natural Science Foundation of China; the National Science Foundation for Distinguished Young Scholars; the Science and Technology Planning Project of Guangdong Province; the National Key Research and Development Programme of China; Guangdong Provincial Clinical Research Centre for Urological Diseases.

Comparison of narrow band imaging versus white light imaging in detecting non muscle invasive bladder cancer

BACKGROUND

In the present study, we compared Narrow Band Imaging (NBI) and White Light Cystoscopy (WLC) in Non-muscle invasive bladder cancer (NMIBC) for detection and its impact on recurrence.

MATERIALS AND METHODS

This prospective study was conducted in the department of Urology at a tertiary institution from August 2021 to April 2023. The main aim was to determine the benefit of addition of NBI during TURBT in NMIBC. All patients with Urinary Bladder Mass (size less than 5 cm on USG/CT) aged >18 years of age planned for TURBT were included.

RESULTS

Amongst 63 patients, the mean age was 59.84 ± 11.3 years; 80% were males. Sixty percent of patients had history of Tobacco consumption and Type II DM was the most common comorbidity (59%). Commonest symptom was gross haematuria. Posterior wall was most commonly involved and papillary lesions were commonest. A total of 125 lesions were identified on WLI, with mean 1.98 ± 1.75 and 78 additional lesions were identified only on NBI with mean 1.24 ± 1.63 lesions. Four patients had intra-operative complications. Five patients had recurrence at 6 weeks and eight patients had recurrence at 3 months. NBI had detected more lesions in patients who developed recurrence at 6 weeks and 3 months (mean: 1.41 and 1.43).

CONCLUSION

NBI has additive role in detecting NMIBC lesions missed on WLI. NBI has significant role in preventing recurrence at 3 months and more so by detecting high grade tumours.

Repeat Transurethral Resection for Non-muscle-invasive Bladder Cancer: An Updated Systematic Review and Meta-analysis in the Contemporary Era

CONTEXT

Repeat transurethral resection (reTUR) is a guideline-recommended treatment strategy in high-risk non-muscle-invasive bladder cancer (NMIBC) patients treated with transurethral resection of bladder tumor (TURBT); however, the impact of recent procedural/technological developments on reTUR outcomes has not been assessed yet.

OBJECTIVE

To assess the outcomes of reTUR for NMIBC in the contemporary era, focusing on whether temporal differences and technical advancement, specifically, photodynamic diagnosis and en bloc resection of bladder tumor (ERBT), affect the outcomes.

EVIDENCE ACQUISITION

Multiple databases were queried in February 2023 for studies investigating reTUR outcomes, such as residual tumor and/or upstaging rates, its predictive factors, and oncologic outcomes, including recurrence-free (RFS), progression-free (PFS), cancer-specific (CSS), and overall (OS) survival. We synthesized comparative outcomes adjusting for the effect of possible confounders.

EVIDENCE SYNTHESIS

Overall, 81 studies were eligible for the meta-analysis. In T1 patients initially treated with conventional TURBT (cTURBT) in the 2010s, the pooled rates of any residual tumors and upstaging on reTUR were 31.4% (95% confidence interval [CI]: 26.0-37.2%) and 2.8% (95% CI: 2.0-3.8%), respectively. Despite a potential publication bias, these rates were significantly lower than those in patients treated in the 1990-2000s (both p < 0.001). ERBT and visual enhancement-guided cTURBT significantly improved any residual tumor rates on reTUR compared with cTURBT based on both matched-cohort and multivariable analyses. Among studies adjusting for the effect of possible confounders, patients who underwent reTUR had better RFS (hazard ratio [HR]: 0.78, 95% CI: 0.62-0.97) and OS (HR: 0.86, 95% CI: 0.81-0.93) than those who did not, while it did not lead to superior PFS (HR: 0.74, 95% CI: 0.47-1.15) and CSS (HR: 0.94, 95% CI: 0.86-1.03).

CONCLUSIONS

reTUR is currently recommended for high-risk NMIBC based on the persistent high rates of residual tumors after primary resection. Improvement of resection quality based on checklist applications and recent technical/procedural advancements hold the promise to omit reTUR.

PATIENT SUMMARY

Recent endoscopic/procedural developments improve the outcomes of repeat resection for high-risk non-muscle-invasive bladder cancer. Further investigations are urgently needed to clarify the potential impact of the use of these techniques on the need for repeat transurethral resection in the contemporary era.

Significance of Normalized Apparent Diffusion Coefficient in the Vesical Imaging-Reporting and Data System for Diagnosing Muscle-Invasive Bladder Cancer

BACKGROUND

Vesical Imaging-Reporting and Data System (VI-RADS) has been developed for assessing bladder cancer from multiparametric (mp) MRI but its performance in diagnosing muscle-invasive bladder cancer (MIBC) is suboptimal.

PURPOSE

To investigate associations between normalized apparent diffusion coefficient (NADC) and clinicopathological characteristics and to determine whether the inclusion of NADC can improve the performance of VI-RADS in diagnosing MIBC.

STUDY TYPE

Retrospective.

POPULATION

Two hundred seventy-five patients with pathologically confirmed bladder cancer (101 MIBC and 174 non-MIBC [NMIBC]) underwent preoperative mpMRI (233 male, 42 female).

FIELD STRENGTH/SEQUENCE

3-T, T2-weighted imaging (turbo spin-echo), diffusion-weighted imaging (free-breathing spin-echo), and dynamic contrast-enhanced imaging (gradient-echo).

ASSESSMENT

NADC was the mean ADC of tumor divided by that of the iliopsoas muscles in trans caput femoris plane. Associations between NADC and clinicopathological characteristics were evaluated. Models were established for differentiating MIBC and NMIBC: VI-RADS model; VN model (VI-RADS and NADC), Images model (significant variables from imaging associated with MIBC), LN model (Images model without NADC), and Full model (all significant variables associated with MIBC).

STATISTICAL TESTS

Variables for model development were based on logistic regression. Models were evaluated by receiver operating characteristic (ROC) curve. Comparison of the area under the curves (AUCs) for the models used DeLong's test. A P value <0.05 was considered statistically significant.

RESULTS

NADC was significantly lower in lesions with diameter ≥ 3 cm, MIBC, histological high grade, lymph node metastasis, and lymphovascular invasion. Compared with VI-RADS model, the AUCs for VN model (VI-RADS score and NADC), Images model (VI-RADS score, NADC and tumor size) and Full model (VI-RADS score, NADC, tumor size and histological grade) were significantly higher. No significant differences were observed between the AUCs for VN model and Images model (P = 0.051).

DATA CONCLUSION

NADC reflects information about the aggressiveness of bladder cancer. Combining VI-RADS with NADC can improve performance in diagnosing MIBC.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: Stage 2.

Recent advancements in the diagnosis and treatment of non-muscle invasive bladder cancer: Evidence update of surgical concept, risk stratification, and BCG-treated disease

In the management of non-muscle invasive bladder cancer (NMIBC), disease progression and long-term control are determined by the intensity of delivered treatment and surveillance and the cancer cells' biological nature. This requires risk stratification-based postoperative management, such as intravesical instillation of chemotherapy drugs, Bacillus Calmette-Guérin (BCG), and radical cystectomy. Advancements in mechanical engineering, molecular biology, and surgical skills have evolved the clinical management of NMIBC. In this review, we describe the updated evidence and perspectives regarding the following aspects: (1) advancements in surgical concepts, techniques, and devices for transurethral resection of the bladder tumor; (2) advancements in risk stratification tools for NMIBC; and (3) advancements in treatment strategies for BCG-treated NMIBC. Repeat transurethral resection, en-bloc transurethral resection, and enhanced tumor visualization, including photodynamic diagnosis and narrow-band imaging, help reduce residual cancer cells, provide accurate diagnosis and staging, and sensitive detection, which are the first essential steps for cancer cure. Risk stratification should always be updated and improved because the treatment strategy changes over time. The BCG-treated disease concept has recently diversified to include BCG failure, resistance, refractory, unresponsiveness, exposure, and intolerance. A BCG-unresponsive disease is an extremely aggressive subset unlikely to respond to a rechallenge with BCG. Numerous ongoing clinical trials aim to develop a future bladder-sparing approach for very high-risk BCG-naïve NMIBC and BCG-unresponsive NMIBC. The key to improving the quality of patient care lies in the continuous efforts to overcome the clinical limitations of bedside management.

Radiomic Analysis of Quantitative T2 Mapping and Conventional MRI in Predicting Histologic Grade of Bladder Cancer

We explored the added value of a radiomic strategy based on quantitative transverse relaxation (T2) mapping and conventional magnetic resonance imaging (MRI) to evaluate the histologic grade of bladder cancer (BCa) preoperatively. Patients who were suspected of BCa underwent pelvic MRI (including T2 mapping and diffusion-weighted imaging (DWI) before any treatment. All patients with histological-proved urothelial BCa were included. We constructed different prediction models using the mean signal values and radiomic features from both T2 mapping and apparent diffusion coefficient (ADC) maps. The diagnostic performance of each model or parameter was assessed using receiver operating characteristic curves. In total, 92 patients were finally included (training cohort, n = 64; testing cohort, n = 28); among these, 71 had high-grade BCa. In the testing cohort, the T2-mapping radiomic model achieved the highest prediction performance (area under the curve (AUC), 0.87; 95% confidence interval (CI), 0.73-1.0) compared with the ADC radiomic model (AUC, 0.77; 95%CI, 0.56-0.97), and the joint radiomic model of 0.78 (95%CI, 0.61-0.96). Our results demonstrated that radiomic mapping could provide more information than direct evaluation of T2 and ADC values in differentiating histological grades of BCa. Additionally, among the radiomic models, the T2-mapping radiomic model outperformed the ADC and joint radiomic models.

Implications of the COVID19 pandemic on the need and timing of second transurethral bladder tumour resection in high-grade non-muscle invasive bladder cancer

PURPOSE

Due to the COVID19 pandemic, the EAU has recommended to, if needed, postpone second transurethral resection of bladder tumour (TURBT) after BCG induction in selected patients. We aimed to evaluate the oncological outcomes of postponed TURBT and the potential to replace second TURBT by routine cystoscopy and cytology.

METHODS

A single-center, retrospective analysis of patients with TaG3/high grade (HG) or T1HG urothelial bladder cancer was performed. All patients underwent a complete TURBT between 2000 and 2013 with presence of detrusor muscle, full BCG induction and routine cystoscopy and cytology, followed by a second TURBT. Results of the cystoscopy, cytology and pathology reports of the TURBT were analyzed by descriptive characteristics, sensitivity, specificity, negative and positive predictive values, as well as survival analyses.

RESULTS

112 patients were included. Residual tumour was present at second TURBT in 21.4%. Upstaging rate from pTaHG to pT1HG and pT1HG to pT2 was 0% and 2.7%, respectively. pT0 was confirmed in 79% of patients, but in 98% of patients with combined negative cytology and cystoscopy after BCG. With a median follow-up of 109 months, the 3-year OS was 85%, RFS 74% and PFS 89%. Sensitivity, specificity, negative predictive value and positive predictive value of cystoscopy and urinary cytology for the presence of residual tumour were 92%, 97%, 98% and 85%, respectively.

CONCLUSION

This study underpins the recommendation of the EAU NMIBC guideline panel that, if needed and in selected patients, second TURBT may be postponed until after BCG induction treatment in pT1HG disease. Also, routine second TURBT can be omitted in pTaHG disease. Data on replacing second TURBT after BCG treatment by routine cystoscopy and cytology appear promising but require further confirmation in prospective studies.

Non-muscle-invasive bladder cancer molecular subtypes predict differential response to intravesical Bacillus Calmette-Guérin

The recommended treatment for patients with high-risk non-muscle-invasive bladder cancer (HR-NMIBC) is tumor resection followed by adjuvant Bacillus Calmette-Guérin (BCG) bladder instillations. However, only 50% of patients benefit from this therapy. If progression to advanced disease occurs, then patients must undergo a radical cystectomy with risks of substantial morbidity and poor clinical outcome. Identifying tumors unlikely to respond to BCG can translate into alternative treatments, such as early radical cystectomy, targeted therapies, or immunotherapies. Here, we conducted molecular profiling of 132 patients with BCG-naive HR-NMIBC and 44 patients with recurrences after BCG (34 matched), which uncovered three distinct BCG response subtypes (BRS1, 2 and BRS3). Patients with BRS3 tumors had a reduced recurrence-free and progression-free survival compared with BRS1/2. BRS3 tumors expressed high epithelial-to-mesenchymal transition and basal markers and had an immunosuppressive profile, which was confirmed with spatial proteomics. Tumors that recurred after BCG were enriched for BRS3. BRS stratification was validated in a second cohort of 151 BCG-naive patients with HR-NMIBC, and the molecular subtypes outperformed guideline-recommended risk stratification based on clinicopathological variables. For clinical application, we confirmed that a commercially approved assay was able to predict BRS3 tumors with an area under the curve of 0.87. These BCG response subtypes will allow for improved identification of patients with HR-NMIBC at the highest risk of progression and have the potential to be used to select more appropriate treatments for patients unlikely to respond to BCG.

VI-RADS in bladder cancer: Overview, pearls and pitfalls

Multiparametric magnetic resonance imaging (mpMRI) of the urinary bladder has shown high diagnostic performance in accurate staging of bladder cancer. Vesical Imaging Reporting and Data System (VI-RADS) scoring was developed in 2018 to standardize imaging and reporting of bladder cancer on mpMRI and is an excellent tool in preoperative T-staging of patients with high risk bladder cancer. However, there is no concise guide in the literature for practical use of VI-RADS in everyday clinical reporting. In this review, we describe our experience with mpMRI in pretreatment workup of bladder cancer, illustrate the imaging characteristics of VI-RADS categories 1 to 5 using case review, and discuss practical pearls and pitfalls in the use of mpMRI and VI-RADS in the hope of providing an accessible reference for radiologists in daily reporting.

[The impact of restaging transurethral resection on recurrence and progression free survival in patients with T1 high grade bladder cancer]

INTRODUCTION

Restaging transurethral resection (re-TUR) of high grade T1 bladder cancer (HGT1-BC) is recommended but the impact in terms of recurrence-free survival (RFS) and progression-free survival (PFS) is discussed. The objective of this study was to evaluate our practice of re-TUR for these tumors and its impact on overall survival (OS), RFS and PFS.

MATERIALS AND METHODS

A retrospective observational study was conducted between 2010 and 2020. The inclusion criteria was the presence of newly diagnosed HGT1-BC. Patients with incomplete resection, suspicion of infiltrating tumor, upper tract urothelial cancer, or metastatic disease were ineligible. Two groups were defined : Group 1 with re-TUR and Group 2 without re-TUR. RFS and PFS were evaluated.

RESULTS

A total of 78 patients were included, including 50 (64,1%) in group 1. There were no significant differences between the two groups. The mean time to re-TUR was 8 weeks and 60% residual tumor was found. Initial under-staging was found in 12% of cases. RFS and PFS were significantly better in Group 1 (P=0.0019; P=0,02). No significant were found between the groups in OS and specific survival (SS).

CONCLUSION

Performing a re-TUR for high grade T1 bladder tumors allows detection of residual tumor and decreases the risk of under-evaluation. It is associated with a significant improvement in RFS and PFS with no impact on OS and SS.

LEVEL OF EVIDENCE: 4

Precise diagnosis and treatment of non-muscle invasive bladder cancer - A clinical perspective

According to the guidelines, transurethral resection of bladder tumor (TURBT) followed by intravesical therapy remains the standard strategy for the management of non-muscle invasive bladder cancer (NMIBC). However, even if patients receive standard strategy, the risk of postoperative recurrence and progression is high. From the clinical perspective, the standard strategy needs to be optimized and improved. Compared to conventional TURBT, the technique of en bloc resection of bladder tumor (ERBT) removes the tumor tissue in one piece, thus following the principles of cancer surgery. Meanwhile, the integrity and spatial orientation of tumor tissue is protected during the operation, which is helpful for pathologists to make accurate histopathological analysis. Then, urologists can make a postoperative individualized treatment plan based on the patient's clinical characteristics and histopathological results. To date, there is no strong evidence that NMIBC patients treated with ERBT achieve better oncological prognosis, which indicates that ERBT alone does not yet improve patient outcomes. With the development of enhanced imaging technology and proteogenomics technology, en bloc resection combined with these technologies will make it possible to achieve precise diagnosis and treatment of bladder cancer. In this review, the authors analyze the current existing shortcomings of en bloc resection and points out its future direction, in order to promote continuous optimization of the management strategy of bladder cancer.

Does repeat transurethral resection of bladder tumor influence the diagnosis and prognosis of T1 bladder cancer? A systematic review and meta-analysis

BACKGROUND

To reduce recurrence or progression of tumor, NCCN guidelines recommend repeat transurethral resection of bladder tumors (reTURB) for non-muscle-invasive bladder cancer (NMIBC). The study aims to compare the impact of initial TURB and reTURB on the rate of residual or upstaging tumors and short-term and long-term survival outcomes of T1 bladder cancer (BC).

MATERIALS AND METHODS

We searched through several public database, including PubMed, Embase, Ovid Medline and Ovid EBM Reviews - Cochrane Central Register of Controlled Trials. The latest search time was October 2021.

RESULTS

In general, 68 articles were involved. Short-term RFS (1-year and 3-year) of reTURB group was better compared with TURB group in T1 patients. The pooled RR were 1.10 (95%CI: 1.01-1.19) and 1.15 (95%CI: 1.03-1.28), respectively. While reTURB did not improve long-term RFS (5-year, 10-year, 15-year) in T1 patients. The pooled RR were 1.12 (95%CI: 0.97-1.30), 1.11 (95%CI: 0.82-1.50) and 1.37 (95%CI: 0.50-3.74), respectively. Analysis of PFS, OS and CSS demonstrated similar outcomes with RFS. We found that about two-thirds of samples contained detrusor. The residual tumor rate in stage T1 was 0.48 (95%CI: 0.42-0.53). While the rate of upstaging in stage T1 was 0.10 (95%CI: 0.07-0.13).

CONCLUSIONS

In conclusion, reTURB might provide short-term survival benefits for T1 BC, but it was not the same for long-term outcomes. The residual and upstaging rates of T1 BC in reTURB were around 50% and 10%, respectively. Our study might be conducive to clinically informed consents when patients expressed their concerns about the necessity of reTURB and its impact on diagnosis, treatment and prognosis.

French AFU Cancer Committee Guidelines - Update 2022-2024: Non-muscle-invasive bladder cancer (NMIBC)

OBJECTIVE

To update the ccAFU recommendations for the management of bladder tumours that do not infiltrate the bladder muscle (NBMIC).

METHODS

A systematic review (Medline) of the literature from 2020 to 2022 was performed, taking account of the diagnosis, treatment options and surveillance of NMIBC, while evaluating the references with their levels of evidence.

RESULTS

The diagnosis of NMIBC (Ta, T1, CIS) is made after complete full-thickness tumour resection. The use of bladder fluorescence and the indication of a second look (4-6 weeks) help to improve the initial diagnosis. The EORTC score is used to assess the risk of recurrence and/or tumour progression. Through the stratification of patients in low, intermediate and high-risk categories, adjuvant treatment can be proposed: intravesical chemotherapy (immediate postoperative, initiation regimen) or BCG (initiation and maintenance regimen) instillations, or even the indication of cystectomy for BCG-resistant patients.

CONCLUSION

Updating the ccAFU recommendations should contribute to improving patient management, as well as the diagnosis and treatment of NMIBC.

Effectiveness of Early Radical Cystectomy for High-Risk Non-Muscle Invasive Bladder Cancer

Purpose: The purpose of this study is to compare perioperative and oncological outcomes of upfront vs. delayed early radical cystectomy (eRC) for high-risk non-muscle-invasive bladder cancer (HR-NMIBC). Methods: All consecutive HR-NMIBC patients who underwent eRC between 2001 and 2020 were retrospectively included and divided into upfront and delayed groups, according to the receipt or not of BCG. Perioperative outcomes were evaluated and the impact of upfront vs. delayed eRC on pathological upstaging, defined as ≥pT2N0 disease at final pathology, was assessed using multivariable logistic regression. Recurrence-free (RFS), cancer-specific (CSS) and overall survival (OS) were compared between upfront and delayed eRC groups using inverse probability of treatment weighting (IPTW)-adjusted Cox model. Results: Overall, 184 patients received either upfront (n = 87; 47%) or delayed (n = 97; 53%) eRC. No difference was observed in perioperative outcomes between the two treatment groups (all p > 0.05). Pathological upstaging occurred in 55 (30%) patients and upfront eRC was an independent predictor (HR = 2.65; 95% CI = (1.23−5.67); p = 0.012). In the IPTW-adjusted Cox analysis, there was no significant difference between upfront and delayed eRC in terms of RFS (HR = 1.31; 95% CI = (0.72−2.39); p = 0.38), CSS (HR = 1.09; 95% CI = (0.51−2.34); p = 0.82) and OS (HR = 1.19; 95% CI = (0.62−2.78); p = 0.60). Conclusion: our results suggest similar perioperative outcomes between upfront and delayed eRC, with an increased risk of upstaging after upfront eRC that did impact survival, as compared to delayed eRC.

What is the impact of dynamic contrast-enhancement sequence in the Vesical Imaging, Reporting and Data System (VI-RADS)? A subgroup analysis

Background

A scoring system focusing on the risk of muscle layer invasion by Bladder cancer (BCa) has been released, Vesical Imaging - Radiological and Data System (VI-RADS), with a growing interest in evaluating its diagnostic accuracy.

Our goal was to assess the accuracy and reproducibility of the VI-RADS score for assessment of the vesical muscular layer with (multiparametric-mp) and without (biparametric-bp) a dynamic-contrast enhancement (DCE) sequence.

Methods

Retrospective study conducted from July 2018 to July 2020. All patients had suspicions of BCa and underwent Magnetic Resonance Imaging (MRI) before any intervention. MRI was interpreted by two radiologists with different levels of experience, and a VI-RADS score assigned in two different sessions (3 months apart) without and with DCE. After exclusions, 44 patients with 50 lesions were enrolled. The standard of reference was transurethral resection in 18 patients (40.9%) and cystectomy in 26 patients (59.1%).

Results

Twenty-five lesions (50%) were muscle-invasive. There was no significant difference between the two groups for gender and presence of a stalk, but mean age of NMIBCa group was significantly higher (p = 0.01). The sizes of lesions were significantly different between groups for both readers at 2.42+/− 1.58 vs. 5.70+/− 2.67 cm for reader 1 (p < 0.0001) and 2.37+/− 1.50 vs. 5.44 +/− 2.90 cm for reader 2 (p = 0.001). The area under the curve (AUC) for muscle invasion with mpVI-RADS, considering all lesions, was 0.885 +/− 0.04 (95% CI-0.79-0.98) for reader 1 and 0.924 +/− 0.04 (0.84–0.99) for reader 2, and for bpVI-RADS was 0.879+/− 0.05 and 0.916 +/− 0.04 (0.85–0.99), respectively, both differences not statistically significant (p = 0.24 and 0.07, respectively). When considering only small lesions (< 3.0 cm), the accuracy for mpVI-RADS was 0.795 +/− 0.11 (0.57–1.0) for reader1, and 0.80 +/− 0.11(0.57–1.0) for reader 2, a non-significant difference (p = 0.56) and for bpVI-RADS was 0.747 +/− 0.12 (0.50–0.99) for reader 1 and 0.80 +/− 0.11(0.57–1.0) for reader 2, a significant difference (p = 0.04). The intraclass correlation coefficient for the final score was 0.81 (0.60–1.0) for mpVI-RADS and 0.85 (0.63–1.0) for bpVI-RADS.

Conclusion

The VI-RADS system was accurate in demonstrating muscle-invasive BCa, for both experienced and less experienced reader, regardless of the use of a DCE sequence. However, when only small lesions were assessed the difference between the two readers was significant only for the biparametric analysis. The reproducibility was similar between multiparametric and biparametric approach.

Biparametric magnetic resonance imaging assessment for detection of muscle-invasive bladder cancer: a systematic review and meta-analysis

OBJECTIVES

To investigate if removing DCE from the Vesical Imaging Reporting and Data System (VI-RADS) influences the diagnostic accuracy of muscle-invasive bladder cancer (MIBC). We also explored using different reference standards on the MRI diagnostic performance.

METHODS

We searched the Cochrane Library, Embase, and PubMed databases to June 26, 2021. Pooled biparametric MRI (bpMRI, T2WI+DWI) and multiparametric MRI (mpMRI, T2WI+DWI+DCE) sensitivities and specificities and the diagnostic performances of these methods for MIBC were compared using different reference standards.

RESULTS

Seventeen studies with 2344 patients were finally included, of which 7 studies, including 1041 patients, reported the diagnostic performance of bpMRI. VI-RADS showed sensitivities and specificities of 0.91 (95% CI 0.87-0.94) and 0.86 (95% CI 0.77-0.91) at cutoff scores of 3, and 0.85 (95% CI 0.77-0.90) and 0.93 (95% CI 0.89-0.96) at cutoff scores of 4. BpMRI showed sensitivities and specificities of 0.90 (95% CI 0.69-0.97) and 0.90 (95% CI 0.81-0.95), and 0.84 (95% CI 0.78-0.88) and 0.97 (95% CI 0.87-0.99), respectively, for cutoff scores of 3 and 4. The sensitivities of bpMRI vs mpMRI for MIBC were not significantly different, but bpMRI was more specific than mpMRI at cutoff scores of 3 (p = 0.02) and 4 (p = 0.02). The VI-RADS studies using primary transurethral resection of bladder tumors (TURBT) as the reference standard had significantly higher sensitivities (p < 0.001) than those using secondary TURBT or radical cystectomy as the reference.

DATA CONCLUSION

BpMRI and conventional VI-RADS had similar diagnostic efficacies for MIBC. Since MRI overestimated MIBC diagnoses using primary TURBT as the reference standard, we recommend using secondary TURBT as the reference standard.

KEY POINTS

• Biparametric MRI without DCE had similar diagnostic efficacies for MIBC compared with conventional VI-RADS. • The sensitivity of VI-RADS was overestimated when referring to the primary TURBT results. • Biparametric MRI comprised of T2WI and DWI could be used for detecting MIBC in clinical practice.

Organocatalytic synthesis and antitumor activity of novel 1,2,3-triazoles derived from fatty β-ketoesters

Background:

Developing methods to synthesize highly functionalized and complex 1,2,3-triazoles from various combinations of substrates remains a significant challenge in organic synthesis. Thus, to the best of our knowledge, an organocatalytic approach to synthesize 1,2,3-triazoles derived from fatty acids has not been explored.

Objective:

In this sense, we describe here the organocatalyzed synthesis and preliminary results of antitumor and cytotoxic activity of a range of 1,2,3-triazoles derived from fatty esters.

Methods:

To synthesize 1,2,3-triazoles 3 derived from fatty β-ketoesters, we performed the reaction of appropriate aryl azides 2a-j with β-ketoesters 1a-c in the presence of 5 mol% of DBU using DMSO as a solvent at 70 °C for 24 h. The viability of 5637 cells was determined by measuring the reduction of soluble MTT to water-insoluble formazan. The IC50 concentration that inhibits 50% of cell growth and the results were obtained by at least three independent experiments in triplicate for each test.

Results:

Through enolate-mediated organocatalysis, 1,2,3-triazoles 3 derived from fatty β-ketoesters were synthesized in moderate to excellent yields by reacting fatty esters 1 with aryl azides 2 in the presence of a catalytic amount of 1,8-diazabicyclo[5.4.0]undec-7-ene (5 mol%). All compounds derived from palmitic acetoacetate 1a were evaluated regarding induced cytotoxicity in vitro in a human bladder cancer cell line, and compounds 3a, 3d, 3e, and 3g were shown to be promising alternatives for bladder cancer treatment and presented the lowest inhibitory concentration of IC50.

Conclusion:

We described a synthetic procedure to prepare 1,2,3-triazoles derived from fatty β-ketoesters by DBU-catalyzed 1,3-dipolar cycloaddition reactions of fatty esters with different aryl azides. Compounds derived from palmitic acetoacetate were screened for antitumor and cytotoxic activity in vitro in human bladder cancer cell lines, and compounds 3a, 3d, 3e, and 3g showed potential to treat bladder cancer.

Risk Stratification for the Rate and Location of Residual Bladder Tumor for the Decision of Re-Transurethral Resection of Bladder Tumor

Introduction

To assess the rate and location of residual tumor in re-transurethral resection of bladder tumor (re-TURBT) and develop a risk stratification tool to assist clinicians in making treatment decisions.

Patients and Methods

The data of 144 patients with high-risk bladder cancer who received re-TURBT were retrospectively reviewed. The rate and location of residual tumors was recorded. Logistic regression was performed to explore risk factors for residual tumors, and a risk classification tool was developed.

Results

Among the 144 patients, the rates of residual tumor and tumor location at the base of the primary tumor were 22.2% and 10.4%, respectively. Non-urothelial carcinoma subspecialist, piecemeal resection and the absence of detrusor muscle in the first specimen were defined as risk factors. Patients were categorized into low-, intermediate-, and high-risk groups according to the number of risk factors. The rate of residual tumor in the high-risk group was significantly higher than that in the low- and intermediate-risk groups (50% vs. 7.8%, P=0.001; 50% vs. 18.6%, P=0.002). Moreover, high-risk patients benefitted more from a second resection at the base of the primary tumor due to the high rate of residual tumor located at this site than low- and intermediate-risk patients (23.5% vs. 2.0%, P=0.002; 23.5% vs. 10.2%, P=0.083).

Conclusions

Risk stratification based on the subspecialist category, operative method, and presence or absence of detrusor muscle in the first specimen could help identify patients who benefit from re-TURBT and second resection the base of the primary tumor.

Restaging transurethral resection in ta high-grade nonmuscle invasive bladder cancer: a systematic review

PURPOSE OF REVIEW

The role of a re-transurethral resection (TUR) is clearly demonstrated in T1 high-grade nonmuscle invasive bladder cancer. However, its role remains controversial for Ta high-risk tumors and the recent European guidelines stated that the second look procedure could be avoided for these patients despite harboring a high-risk of both disease recurrence and progression. We aimed to evaluate the added benefit on staging, response to bacillus Calmette-Guérin and oncological outcomes of re-TUR in patients with Ta high-grade nonmuscle invasive bladder cancer.

RECENT FINDINGS

Overall, we identified 15 studies, including 3912 patients from which 743 harbored Ta high-grade disease. Delay between first and second TUR was ranging from 2 to 12 weeks (median 5.6 weeks). The rate of residual disease was 52.8% (range 17-67%). The rate of overall upstaging to T1 and muscle-invasive disease were 10.9 and 4.7%, respectively. Although there was a trend toward improvement of recurrence-free survival outcomes, no definitive conclusions can be drawn due to the retrospective design of the studies included.

SUMMARY

Residual tumor is common after initial TUR for Ta high-grade. Re-TUR is useful in reducing the rates of residual disease, may improve staging, response to bacillus Calmette-Guérin and oncological outcomes.

[Transurethral resection of bladder tumors (TURBT)]

Transurethral resection of bladder tumors (TURBT) is the standard of care for the diagnostics and primary treatment of bladder tumors. These are removed by fragmentation using loop diathermy. The resection area is coagulated for hemostasis. An important aspect is always a complete resection with an adequate amount of detrusor muscle in the specimen. Postoperative intravesical instillation of single-shot chemotherapy has been proven to reduce recurrence rates. Methods for improved tumor visualization (particularly photodynamic diagnostics) are used to enhance tumor detection rates particularly in multifocal tumors or carcinoma in situ (CIS). Thus, recurrence and progression rates can be reduced. Depending on the histological examination of the TURBT specimen, follow-up treatment for non-muscle invasive bladder tumors are adjuvant instillation treatment using chemotherapy or Bacillus Calmette-Guérin (BCG), second look TURBT and early cystectomy or for muscle invasive bladder tumors, radical cystectomy or (oncologically subordinate) trimodal treatment with renewed TURBT, radiotherapy and chemotherapy are indicated. Possible complications of TURBT include bleeding with bladder tamponade, extraperitoneal or intraperitoneal bladder perforation and infections of the urogenital tract.

Role of Vesical Imaging-Reporting and Data System in predicting muscle-invasive bladder cancer: A diagnostic meta-analysis

The objective of this study is to systematically evaluate the diagnostic performance of the Vesical Imaging-Reporting and Data System for predicting muscle-invasive bladder cancer. Embase, PubMed and Web of Science were systematically searched from 1 September 2018 to 30 July 2021 to include proper studies. We included studies that included data on Vesical Imaging-Reporting and Data System and their associated pathological findings, and we assessed their quality using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The pooled sensitivity and specificity were calculated and plotted using hierarchical summary receiver operating characterisijutic modeling. Meta-regression analysis was carried out to detect heterogeneity. A total of 20 studies with 2725 patients were included. When the cut-off point was 3, the pooled sensitivity and specificity were 0.92 (0.89-0.94) and 0.85 (0.78-0.90), respectively, and 0.82 (0.75-0.88) and 0.95 (0.91-0.97), respectively, when the cut-off point was 4. The area under the curve was 0.95 and 0.95, respectively. Heterogeneity was substantially considerable in sensitivity and specificity. All subgroup variables, including patient number, study design, magnetic resonance imaging field strength, number of radiologists, surgery pattern, diffusion-weighted imaging, and dynamic contrast-enhanced magnetic resonance imaging, contributed to sensitivity heterogeneity when the cut-off point was 3 and specificity heterogeneity when the cut-off point was 4. Multiple image acquisition plane of diffusion-weighted imaging achieved a higher sensitivity than single image acquisition plane of diffusion-weighted imaging in both the Vesical Imaging-Reporting and Data System 3 and 4 groups, and higher specificity in the Vesical Imaging-Reporting and Data System 4 group. Another significant source of heterogeneity was the cut-off point. The diagnostic performance of the Vesical Imaging-Reporting and Data System for predicting muscle-invasive bladder cancer was excellent in both cut-off points of the Vesical Imaging-Reporting and Data System 3 and 4. Multiple image acquisition planes of diffusion-weighted imaging should be given more attention in the Vesical Imaging-Reporting and Data System.

European Association of Urology Guidelines on Non-muscle-invasive Bladder Cancer (Ta, T1, and Carcinoma in Situ)

CONTEXT

The European Association of Urology (EAU) has released an updated version of the guidelines on non-muscle-invasive bladder cancer (NMIBC).

OBJECTIVE

To present the 2021 EAU guidelines on NMIBC.

EVIDENCE ACQUISITION

A broad and comprehensive scoping exercise covering all areas of the NMIBC guidelines since the 2020 version was performed. Databases covered by the search included Medline, EMBASE, and the Cochrane Libraries. Previous guidelines were updated, and the level of evidence and grade of recommendation were assigned.

EVIDENCE SYNTHESIS

Tumours staged as Ta, T1 and carcinoma in situ (CIS) are grouped under the heading of NMIBC. Diagnosis depends on cystoscopy and histological evaluation of tissue obtained via transurethral resection of the bladder (TURB) for papillary tumours or via multiple bladder biopsies for CIS. For papillary lesions, a complete TURB is essential for the patient's prognosis and correct diagnosis. In cases for which the initial resection is incomplete, there is no muscle in the specimen, or a T1 tumour is detected, a second TURB should be performed within 2-6 wk. The risk of progression may be estimated for individual patients using the 2021 EAU scoring model. On the basis of their individual risk of progression, patients are stratified as having low, intermediate, high, or very high risk, which is pivotal to recommending adjuvant treatment. For patients with tumours presumed to be at low risk and for small papillary recurrences detected more than 1 yr after a previous TURB, one immediate chemotherapy instillation is recommended. Patients with an intermediate-risk tumour should receive 1 yr of full-dose intravesical bacillus Calmette-Guérin (BCG) immunotherapy or instillations of chemotherapy for a maximum of 1 yr. For patients with high-risk tumours, full-dose intravesical BCG for 1-3 yr is indicated. For patients at very high risk of tumour progression, immediate radical cystectomy should be considered. Cystectomy is also recommended for BCG-unresponsive tumours. The extended version of the guidelines is available on the EAU website at https://uroweb.org/guideline/non-muscle-invasive-bladder-cancer/.

CONCLUSIONS

These abridged EAU guidelines present updated information on the diagnosis and treatment of NMIBC for incorporation into clinical practice.

PATIENT SUMMARY

The European Association of Urology has released updated guidelines on the classification, risk factors, diagnosis, prognostic factors, and treatment of non-muscle-invasive bladder cancer. The recommendations are based on the literature up to 2020, with emphasis on the highest level of evidence. Classification of patients as having low, intermediate, or and high risk is essential in deciding on suitable treatment. Surgical removal of the bladder should be considered for tumours that do not respond to bacillus Calmette-Guérin (BCG) treatment and tumours with the highest risk of progression.

Novel Visualization Methods Assisted Transurethral Resection for Bladder Cancer: An Updated Survival-Based Systematic Review and Meta-Analysis

Background

Photodynamic diagnosis and narrow-band imaging could help improve the detection rate in transurethral resection (TUR) of bladder cancer. It remained controversial that the novel visualization method assisted transurethral resection (VA-TUR) could elongate patients' survival compared to traditional TUR.

Methods

We performed electronic and manual searching until December 2020 to identify randomized controlled trials comparing VA-TUR with traditional TUR, which reported patients' survival data. Two reviewers independently selected eligible studies, extracted data, assessed the risk of bias. Meta-analysis was conducted according to subgroups of types of visualization methods (A) and clinical stage of participants. Publication bias was detected.

Results

We included 20 studies (reported in 28 articles) in this review. A total of 6,062 participants were randomized, and 5,217 participants were included in the analysis. Only two studies were assessed at low risk of bias. VA-TURB could significantly improve the recurrence-free survival (RFS) (HR = 0.72, 95% CI: 0.66 to 0.79, P <0.00001, I² = 42%) and progression-free survival (PFS) (HR = 0.62, 95% CI: 0.46 to 0.82, P <0.0008, I² = 0%) compared with TUR under white light. The results remain stable whatever the type of visualization method. The difference could be observed in the non-muscle-invasive bladder cancer (NMIBC) population (P <0.05) but not in the mixed population with muscle-invasive bladder cancer (MIBC) participants (P >0.05).

Conclusion

VA-TUR could improve RFS and PFS in NMIBC patients. No significant difference is found among different types of VA-TUR. VA-TUR may be not indicated to MIBC patients.

Novel transurethral resection technologies and training modalities in the management of nonmuscle invasive bladder cancer: a comprehensive review

PURPOSE OF REVIEW

Conventional transurethral resection (TURBT) with tumor fragmentation is the primary step in the surgical treatment of nonmuscle invasive bladder cancer. Recently, new surgical techniques and training modalities have emerged with the aim to overcome short-comings of TURBT and improve oncologic outcomes. In this review, we provide a comprehensive update of recent techniques/techniques that aim to improve upon conventional TURBT and beyond.

RECENT FINDINGS

A systemic approach during conventional TURBT that features the use of a surgical checklist has been shown to improve recurrence-free survival. Several simulators have been developed and validated to provide additional training opportunities. However, transfer of improved simulator performance into real world surgery still requires validation. While there is no convincing data that demonstrate superior outcomes with bipolar TURBT, en-bloc resection already promises to offer lower rates of complications as well as potentially lower recurrence probabilities in select patients.

SUMMARY

TURBT remains the quintessential procedure for the diagnosis and treatment of bladder cancer. Urologists need to be aware of the importance and challenges of this procedure. Aside of embracing new resection techniques and a conceptual-systematic approach, training opportunities should be expanded upon to improve patient outcomes.

[French ccAFU guidelines - update 2020-2022: bladder cancer]

OBJECTIVE

- To update French guidelines for the management of bladder cancer specifically non-muscle invasive (NMIBC) and muscle-invasive bladder cancers (MIBC).

METHODS

- A Medline search was achieved between 2018 and 2020, notably regarding diagnosis, options of treatment and follow-up of bladder cancer, to evaluate different references with levels of evidence.

RESULTS

- Diagnosis of NMIBC (Ta, T1, CIS) is based on a complete deep resection of the tumor. The use of fluorescence and a second-look indication are essential to improve initial diagnosis. Risks of both recurrence and progression can be estimated using the EORTC score. A stratification of patients into low, intermediate and high risk groups is pivotal for recommending adjuvant treatment: instillation of chemotherapy (immediate post-operative, standard schedule) or intravesical BCG (standard schedule and maintenance). Cystectomy is recommended in BCG-refractory patients. Extension evaluation of MIBC is based on contrast-enhanced pelvic-abdominal and thoracic CT-scan. Multiparametric MRI can be an alternative. Cystectomy associated with extended lymph nodes dissection is considered the gold standard for non-metastatic MIBC. It should be preceded by cisplatin-based neoadjuvant chemotherapy in eligible patients. An orthotopic bladder substitution should be proposed to both male and female patients with no contraindication and in cases of negative frozen urethral samples; otherwise transileal ureterostomy is recommended as urinary diversion. All patients should be included in an Early Recovery After Surgery (ERAS) protocol. For metastatic MIBC, first-line chemotherapy using platin is recommended (GC or MVAC), when performans status (PS <1) and renal function (creatinine clearance >60 mL/min) allow it (only in 50% of cases). In second line treatment, immunotherapy with pembrolizumab demonstrated a significant improvement in overall survival.

CONCLUSION

- These updated French guidelines will contribute to increase the level of urological care for the diagnosis and treatment of patients diagnosed with NMIBC and MIBC.

Non-Muscular Invasive Bladder Cancer: Re-envisioning Therapeutic Journey from Traditional to Regenerative Interventions

Non-muscular invasive bladder cancer (NMIBC) is one of the most common cancer and major cause of economical and health burden in developed countries. Progression of NMIBC has been characterized as low-grade (Ta) and high grade (carcinoma in situ and T1). The current surgical intervention for NMIBC includes transurethral resection of bladder tumor; however, its recurrence still remains a challenge. The BCG-based immunotherapy is much effective against low-grade NMIBC. BCG increases the influx of T cells at bladder cancer site and inhibits proliferation of bladder cancer cells. The chemotherapy is another traditional approach to address NMIBC by supplementing BCG. Notwithstanding, these current therapeutic measures possess limited efficacy in controlling NMIBC, and do not provide comprehensive long-term relief. Hence, biomaterials and scaffolds seem an effective medium to deliver therapeutic agents for restructuring bladder post-treatment. The regenerative therapies such as stem cells and PRP have also been explored for possible solution to NMIBC. Based on above-mentioned approaches, we have comprehensively analyzed therapeutic journey from traditional to regenerative interventions for the treatment of NMIBC.

Differential Prognosis and Response of Denovo vs. Secondary Muscle-Invasive Bladder Cancer: An Updated Systematic Review and Meta-Analysis

Simple Summary

Bladder cancer is one of the leading causes of death worldwide. About 75% of patients initially present with non-muscle-invasive disease, while the rest presents with primary muscle-invasive disease. Up to a third of non-muscle-invasive bladder cancers progresses into secondary muscle-invasive bladder cancer. Little is known about clinical outcomes after upfront neoadjuvant cisplatin-based chemotherapy and subsequent radical cystectomy for secondary muscle-invasive bladder cancer compared to primary muscle-invasive bladder cancer. Here, we systematically reviewed the current literature evaluate oncological outcomes between primary and secondary muscle-invasive bladder cancer.

Abstract

To evaluate oncological outcomes of primary versus secondary muscle-invasive bladder cancer treated with radical cystectomy. Medline, Embase, Scopus and Cochrane Library were searched for eligible studies. Hazard ratios for overall survival (OS), cancer specific survival (CSS) and progression free survival (PFS) were calculated using survival data extracted from Kaplan-Meier curves. A total of 16 studies with 5270 patients were included. Pooled analysis showed similar 5-year and 10-year OS (HR 1, p = 0.96 and HR 1, p = 0.14) and CSS (HR 1.02, p = 0.85 and HR 0.99, p = 0.93) between primMIBC and secMIBC. Subgroup analyses according to starting point of follow-up and second-look transurethral resection revealed similar results. Subgroup analyses of studies in which neoadjuvant chemotherapy was administered demonstrated significantly worse 5-year CSS (HR 1.5, p = 0.04) but not 10-year CSS (HR 1.36, p = 0.13) in patients with secMIBC. Patients with secMIBC had significantly worse PFS at 5-year (HR 1.41, p = 0.002) but not at 10-year follow-up (HR 1.25, p = 0.34). This review found comparable oncologic outcomes between primMIBC and secMIBC patients treated with RC regarding OS and CSS. Subgroup analysis showed worse 5-year CSS but not 10-year CSS for neoadjuvant chemotherapy in the secMIBC group. Prospective clinical trials incorporating molecular markers, that allow precise risk stratification of secMIBC and further research uncovering underlying molecular and clinical drivers of the heterogeneous group of secMIBC is needed.

MRI and CT bladder segmentation from classical to deep learning based approaches: Current limitations and lessons

Precise determination and assessment of bladder cancer (BC) extent of muscle invasion involvement guides proper risk stratification and personalized therapy selection. In this context, segmentation of both bladder walls and cancer are of pivotal importance, as it provides invaluable information to stage the primary tumor. Hence, multiregion segmentation on patients presenting with symptoms of bladder tumors using deep learning heralds a new level of staging accuracy and prediction of the biologic behavior of the tumor. Nevertheless, despite the success of these models in other medical problems, progress in multiregion bladder segmentation, particularly in MRI and CT modalities, is still at a nascent stage, with just a handful of works tackling a multiregion scenario. Furthermore, most existing approaches systematically follow prior literature in other clinical problems, without casting a doubt on the validity of these methods on bladder segmentation, which may present different challenges. Inspired by this, we provide an in-depth look at bladder cancer segmentation using deep learning models. The critical determinants for accurate differentiation of muscle invasive disease, current status of deep learning based bladder segmentation, lessons and limitations of prior work are highlighted.

Comparison of Re-TUR Results in Primary Patients with Non-muscle-Invasive Bladder Cancer (NMIBC) of Low, Intermediate, and High-risk for Recurrence Based on the EORTC Scoring System

Background: Bladder cancer is the second most common urologic malignancy. Transurethral resection (TUR) is the standard initial treatment for non-muscle-invasive bladder cancer (NMIBC). The high prevalence of residual tumor in some patients has necessitated repeat TUR (re-TUR). Previous studies have shown the quality of primary resection to impact re-TUR outcomes, but the role of tumor biology remains unclear. Objectives: This study aimed to evaluate the impact of tumor biology on re-TUR results in primary (non-recurrent) patients with superficial bladder tumors. Methods: We studied a cohort of consecutive primary patients with superficial bladder cancer undergoing resection and routine re-TUR between March 2018 and February 2019 at our unit. Patients with TaG1 or T2 on primary pathologic report, deliberately incomplete initial resection, or absence of detrusor muscle on the initial specimen were excluded from the study. Re-TUR was performed in the sixth week. All procedures were performed by the same surgeon. The patients were divided into three groups according to the European Organization for Research and Treatment of Cancer (EORTC) risk scoring system and compared for recurrence of NMIBC. Results: Of 58 primary patients, 16 were classified as low-risk, 32 as intermediate-risk, and 10 as high-risk. The mean age of subjects was 62.1 years. Residual tumor was detected on re-TUR in 19 (32.7%) cases. Also, 3 (5.2%) cases entailed stage progression to pT2, all of whom belonged to the high-risk group. Residual tumor rate was 0%, 40.6%, and 60% in the low-, intermediate-, and high-risk groups, respectively. In addition, 13 patients had macroscopic residual. Conclusions: Despite the modest study size, our results suggest that tumor biology might have an impact on residual tumor characteristics, and the EORTC scoring system may help to predict the risk of progression and residual tumor rate on re-TUR.

A urine-based DNA methylation assay to facilitate early detection and risk stratification of bladder cancer

Background

Current non-invasive tests have limited sensitivities and lack capabilities of pre-operative risk stratification for bladder cancer (BC) diagnosis. We aimed to develop and validate a urine-based DNA methylation assay as a clinically feasible test for improving BC detection and enabling pre-operative risk stratifications.

Methods

A urine-based DNA methylation assay was developed and validated by retrospective single-center studies in patients of suspected BC in Cohort 1 (n = 192) and Cohort 2 (n = 98), respectively. In addition, a prospective single-center study in hematuria patient group (Cohort 3, n = 174) was used as a second validation of the model.

Results

The assay with a dual-marker detection model showed 88.1% and 91.2% sensitivities, 89.7% and 85.7% specificities in validation Cohort 2 (patients of suspected BC) and Cohort 3 (patients of hematuria), respectively. Furthermore, this assay showed improved sensitivities over cytology and FISH on detecting low-grade tumor (66.7–77.8% vs. 0.0–22.2%, 0.0–22.2%), Ta tumor (83.3% vs. 22.2–41.2%, 44.4–52.9%) and non-muscle invasive BC (NMIBC) (80.0–89.7% vs. 51.5–52.0%, 59.4–72.0%) in both cohorts. The assay also had higher accuracies (88.9–95.8%) in diagnosing cases with concurrent genitourinary disorders as compared to cytology (55.6–70.8%) and FISH (72.2–77.8%). Meanwhile, the assay with a five-marker stratification model identified high-risk NMIBC and muscle invasive BC with 90.5% sensitivity and 86.8% specificity in Cohort 2.

Conclusions

The urine-based DNA methylation assay represents a highly sensitive and specific approach for BC early-stage detection and risk stratification. It has a potential to be used as a routine test to improve diagnosis and prognosis of BC in clinic.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-021-01073-x.

Can repeat biopsy be skipped after initial complete resection of T1 bladder cancer? The role of a novel urinary mRNA biomarker

OBJECTIVES

To prospectively investigate the role of a urinary mRNA biomarker (Xpert Test) after initial complete resection of T1 bladder cancer (BC) for the prediction of positive repeat biopsy for malignancy.

METHODS

Patients who underwent TURBT for NMIBC between September 2018 and April 2020 were included. Patients with benign pathology, incomplete resection, concomitant CIS/upper tract urothelial tumor or muscle invasive BC, were excluded. 2 to 6 weeks after primary TURBT, voided urine sample was retrieved for Xpert analysis and patients were scheduled for repeat biopsy. The primary outcome was to determine the role of positive Xpert test to predict positive repeat biopsy for malignancy.

RESULTS

During the study period, 254 patients met the study inclusion criteria of which 61 (24%) patients had recurrent NMIBC. Complete resection was censured by the presence of detrusor muscle in the specimen with documented T1 disease in all study participants. Xpert test was positive in 128 patients; of whom 85 (66.4%) showed positive repeat biopsy (HR=6.2, 95%CI=3.46-9.4, P = 0.002). The sensitivity, specificity, positive and negative predictive values of Xpert test for repeat biopsy were 85.9% (95%CI: 82-89), 72.3% (95%CI: 68-76), 66.4% (95%CI: 62-71) and 88.9% (95%CI: 85-94), respectively. On median (range) follow up of 12(3-25) months, tumor recurrence was encountered in 84 (35%) patients. On multivariate Cox regression analysis, Xpert test was significantly associated with tumor recurrence (HR= 9.7, 95%CI=5-18, P <0.001).

CONCLUSIONS

Positive Xpert test after primary complete resection of T1 BC is significantly associated with positive repeat biopsy for malignancy. In addition, Xpert test is an independent predictor of early tumor recurrence. Xpert test might be applied after initial complete resection of NMIBC to minimize unnecessary repeat biopsy with potential saving of healthcare costs and reduction in patient morbidity.

En Bloc Tumor Resection, Optical Molecular Imaging, and the Potential Synergy of the Combination of the Two Techniques in Bladder Cancer

Although transurethral resection of bladder tumor is the golden standard for the treatment of non-muscle invasive bladder cancer, this surgical procedure still has some serious drawbacks. For example, piecemeal resection of tumor tissue results in exfoliated tumor cells dissemination and implantation, and fragmented tumor specimens make it difficult for pathologists to accurately assess the pathological stage and histologic grade. En bloc tumor resection follows the basic principle of oncological surgery and provides an intact tumor specimen containing detrusor muscle for pathologists to make accurate histopathological assessment. However, there is no robust clinical evidence that en bloc tumor resection is superior to conventional resection in terms of oncological outcomes. Considering the high recurrence rate, small or occult tumor lesions may be overlooked and incomplete tumor resection may occur during white light cystoscopy-assisted transurethral resection. Molecular fluorescent tracers have the ability to bind tumor cells with high sensitivity and specificity. Optical molecular imaging mediated by it can detect small or occult malignant lesions while minimizing the occurrence of false-positive results. Meanwhile, optical molecular imaging can provide dynamic and real-time image guidance in the surgical procedure, which helps urologists to accurately determine the boundary and depth of tumor invasion, so as to perform complete and high-quality transurethral tumor resection. Integrating the advantages of these two technologies, optical molecular imaging-assisted en bloc tumor resection shows the potential to improve the positive detection rate of small or occult tumor lesions and the quality of transurethral resection, resulting in high recurrence-free and progression-free survival rates.

VI-RADS score and tumor contact length in MRI: A potential method for the detection of muscle invasion in bladder cancer

BACKGROUND

Vesical Imaging Reporting and Data System (VI-RADS) is a useful tool for evaluating muscle layer invasion of bladder cancer (BCa) on magnetic resonance imaging (MRI).

PURPOSE

To evaluate the diagnostic performance of bladder MRI to detect the muscle layer invasion of BCa using VI-RADS score and quantitative MRI parameters.

METHODS

Preoperative bladder MRI was performed in 73 BCa patients. Two observers independently evaluated the MR blinded to histopathological data and classified the tumors according to VI-RADS criteria. Moreover, the quantitative parameters (maximum tumor diameter; Dmax, tumor contact length; TCL, and tumor apparent diffusion coefficient; ADC values) were independently measured by observers. The diagnostic performance of the VI-RADS score and quantitative values were evaluated by using receiver operating characteristic (ROC) analysis. Interobserver agreement was evaluated using the weighted-kappa coefficient (κ).

RESULTS

For the VI-RADS score, the AUC (area under the curve) was 0.968 and accuracy was 90.4% for Observer 1, and AUC was 0.953, accuracy was 89% for Observer 2. The AUC of TCL, TCL/DMax, and ADC values was 0.918, 0.675, and 0.832. In patients with a VI-RADS score ≥ 3, when a threshold value of TCL > 19.5 mm is used as complementary to the VI-RADS score, the accuracy of MRI for Observer-1 increases 100% and 97.26% for Observer-2. There was a good-excellent agreement between the observers in assessing the VI-RADS scores and quantitative parameters.

CONCLUSION

Evaluation of bladder MRI using both VI-RADS criteria and TCL is successful and highly reproducible for detecting muscle layer invasion in patients with BCa.

Holmium Laser En-bloc Resection Versus Conventional Transurethral Resection of Bladder Tumors for Treatment of Non-muscle-invasive Bladder Cancer: A Randomized Clinical Trial

BACKGROUND

En-bloc resection of bladder tumors achieves complete tumor removal, improves the quality of resection, decreases perioperative complication, and potentially improves recurrence rates.

OBJECTIVE

To assess the efficacy and safety of holmium laser en-bloc resection (HolERBT) versus conventional transurethral resection of bladder tumor (cTURBT).

DESIGN, SETTING, AND PARTICIPANTS

Between September 2015 and September 2018, 100 patients with non-muscle-invasive bladder cancer were randomly allocated to cTURBT or HolERBT.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was detection of residual tumor in reTURBT specimens at 4 wk after the primary resection. Operative parameters, specimen quality, perioperative complications, and recurrence-free survival (RFS) were compared. Independent sample t tests, χ² tests, and Kaplan-Meier curves were used, as appropriate.

RESULTS AND LIMITATIONS

The patient and tumor baseline characteristics were comparable between the groups. Residual tumors were detected in 7% and 27.7% of cases after HolERBT and cTURBT, respectively (p=0.01). Detrusor muscle was sampled in 98% of HolERBT and 62% of cTURBT cases (p<0.001). Lamina propria invasion substaging was feasible in only 68.2% of HolERBT and 18.4% of cTURBT cases (p<0.001). Following HolERBT, catheterization time (p<0.001) and hospital stay (p=0.001) were shorter when compared to cTURBT. Immediate postoperative instillation of chemotherapy in indicated cases was feasible for 100% of the HolERBT group and 91.5% of the cTURBT group (p=0.04). After follow-up of 20 ± 9.9 mo (13-36), RFS was 31.76 mo (95% confidence interval [CI] 28.67-34.86) in the HolERBT group and 28.25 mo (95% CI 24.87-31.64) in the cTURBT group (hazard ratio 0.43, 95% CI 0.17-1.1; p=0.07). However, this study was not powered to detect a difference in RFS.

CONCLUSIONS

Compared to cTURBT, HolERBT is a safer procedure for bladder tumor resection. It fulfills the oncological criteria of optimized resection with less residual tumor and better specimen quality.

PATIENT SUMMARY

En-bloc resection of bladder cancer tumors using a holmium laser is safer than the conventional technique. It has the advantages of less residual tumor and better specimen quality, with a similar tumor recurrence rate. This study is registered at ClinicalTrials.gov as NCT02555163.

Utilization of imaging for staging in bladder cancer: is there a role for MRI or PET-computed tomography?

PURPOSE OF REVIEW

Accurate staging of bladder cancer is essential to guide appropriate management. In this review, we discuss the principles, applications and performance of multiparametric MRI (mpMRI) and PET-computer tomography (PET-CT) for local and distant staging of bladder cancer.

RECENT FINDINGS

Bladder mpMRI has a high diagnostic performance in local staging of bladder cancer, superior to other imaging modalities. It can accurately differentiate muscle invasive bladder cancer (MIBC) from non-MIBC (NMIBC), as well as ≤T2 from ≥T3 stages. mpMRI can be used to assess pelvic lymph nodes, although its sensitivity is relatively low. For the assessment of the upper urinary tract, CT urography is the imaging modality of choice. magnetic resonance urography is a viable alternative to CT in selected cases. Although PET-CT is accurate for nodal and distant staging of bladder cancer, there is no clear evidence on its superior diagnostic performance compared with contrast-enhanced CT.

SUMMARY

mpMRI is the most accurate imaging modality for local staging of bladder cancer, capable to accurately distinguish MIBC from NMIBC. Nodal and distant staging relies primarily on contrast-enhanced CT.

Transurethral resection of bladder tumor and the need for re-transurethral resection of bladder tumor: time to change our practice?

PURPOSE OF REVIEW

To summarize the current knowledge on the role of repeated transurethral resection of the bladder (re-TURBT) at the light of recently published trials that indicate the possibility to safely avoid it in well selected patients.

RECENT FINDINGS

Recently published trials tried to predict the histology of re-TURBT with the aim of improving patients' selection for this procedure. The en bloc resection technique seems to improve the quality of the resection, thereby diminishing and even eliminating the risk of upstaging and the residual disease rate after TURBT. Moreover, the introduction of multiparametric MRI (mpMRI) in bladder cancer showed initial promising results and aims, in the next future, to play a role in the selection of patients for re-TURBT.

SUMMARY

International guidelines agree to recommend re-TURBT in case of incomplete first resection and in T1 tumors. Conversely, the performance of re-TURBT in case of high-grade/high-risk Ta or in case of absence of detrusor muscle in TURBT specimen remains a matter of debate. Re-TURBT aims to reduce the risk of understaging the disease and to remove residual disease in case of persistent nonmuscle invasive bladder cancer. Actually, upstaging at re-TURBT is not a negligible event in T1 tumors (8-15%), while is quite uncommon in case of Ta tumors (0.4%). Residual disease at re-TURBT is usually found in the majority of patients (55-60%) and seems to impact oncological outcomes, even if recent evidence mitigated its relevance as prognostic factor.

Transurethral resection of bladder tumour (TURBT)

The goals of transurethral resection of bladder tumour (TURBT) are to identify and eradicate visualized bladder tumour if technically safe and feasible and to obtain a specimen of satisfactory quality to enable accurate histological diagnosis. In the setting of high grade bladder tumour this generally entails the inclusion of detrusor muscle and assessment for the presence of associated carcinoma in situ (CIS), lymphovascular involvement or any variant form of bladder cancer. This will assist in determining risk stratification and prognostication of the bladder cancer and guides further treatment planning. Conversely, if suboptimal TURBT is performed there will be detrimental consequences on patient outcomes in regards to undergrading or understaging, increased recurrence or progression, and subsequently need for further treatments including more invasive interventions. This review article firstly summarises the key principles and complications of TURBT, as well as significance of re-TURBT. We also discuss a number of modifications and advances in detection technology and resection techniques that have shown to improve perioperative as well as pathological and oncological outcomes of bladder cancer. They include enhanced cystoscopy such as blue light cystoscopy (BLC), narrow band imaging (NBI) and en bloc resection of bladder tumour (ERBT) technique using various types of energy source.

Stage T1 bladder cancer: diagnostic criteria and pitfalls

Accurate pathological staging is crucial for patient management. Patients with T1 bladder cancer are at risk of recurrence, progression, and death of cancer. Recognition of early invasion (stage T1 disease) in urothelial carcinoma remains one of the most challenging areas in urological surgical pathology practice. A logical roadmap to T1 diagnosis would include careful evaluation of histological grade, stromal epithelial interface, characteristics of the invading epithelium, and the stroma associated responses. Tangential sectioning, crush and cautery artifacts, and associated inflammatory infiltrate are commonly encountered problems and the source of pitfalls. In this review, we outline diagnostic criteria, common pitfalls, and different histological patterns of invasion into the lamina propria. Current recommendations on reporting of biopsy and transurethral resection specimens, molecular biomarkers, clinical implications of T1 cancer diagnosis and recent developments on the T1 substaging are also discussed. Most T1 bladder cancer patients will benefit from conservative management after restaging transurethral resection of bladder and bacillus Calmette-Guérin maintenance. Patients with high risk features, such as concurrent urothelial carcinoma in situ, increased depth of invasion, lymphovascular invasion, and variant histology among others, should be considered for early cystectomy.

Restaging Transurethral Resection of Bladder Tumours after BCG Immunotherapy Induction in Patients with T1 Non-Muscle-Invasive Bladder Cancer Might not Be Associated with Oncologic Benefit

BACKGROUND AND PURPOSE

The European Association of Urology guidelines recommend restaging transurethral resection of bladder tumours (reTURB) 2-6 weeks after primary TURB. However, in clinical practice some patients undergo a second TURB procedure after Bacillus Calmette-Guérin immunotherapy (BCG)induction. To date, there are no studies comparing post-BCG reTURB with the classic pre-BCG approach. The aim of this study was to assess whether the performance of reTURB after BCG induction in T1HG bladder cancer is related to potential oncological benefits.

MATERIALS AND METHODS

Data from 645 patients with primary T1HG bladder cancer treated between 2001 and 2019 in 12 tertiary care centres were retrospectively reviewed. The study included patients who underwent reTURB before BCG induction (Pre-BCG group: 397 patients; 61.6%) and those who had reTURB performed after BCG induction (Post-BCG group: 248 patients, 38.4%). The decision to perform reTURB before or after BCG induction was according to the surgeon's discretion, as well as a consideration of local proceedings and protocols. Due to variation in patients' characteristics, both propensity-score-matched analysis (PSM) and inverse-probability weighting (IPW) were implemented.

RESULTS

The five-year recurrence-free survival (RFS) was 64.7% and 69.1% for the Pre- and Post-BCG groups, respectively, and progression-free survival (PFS) was 82.7% and 83.3% for the Pre- and Post-BCG groups, respectively (both: p > 0.05). Similarly, neither RFS nor PFS differed significantly for a five-year period or in the whole time of observation after the PSM and IPW matching methods were used.

CONCLUSIONS

Our results suggest that there might be no difference in recurrence-free survival and progression-free survival rates, regardless of whether patients have reTURB performed before or after BCG induction.

The impact of tumor invasion to muscularis mucosaevascular plexus on patient outcome in pT1 bladder urothelial carcinoma

OBJECTIVES

T1 bladder cancer has a wide range of tumor behavior and lamina propria invasion depth has a high potential risk of disease progression. To evaluate the patient outcome according to the tumor invasion to the muscularis mucosae-vascular plexus (MM-VP) in pT1 bladder urothelial carcinoma (BUC).

MATERIALS AND METHODS

This study is a retrospective analysis of patients consecutively recorded from 2007 to 2013. A total of 93 patients with a history of primary pT1 BUC and complete follow-up were included. We used a pathological substaging system according to the tumor invasion regarding the MM-VP: pT1a (invasion above MM-VP) and pT1b (MM-VP invasion). We evaluated recurrence-free survival (RFS), progression- free survival (PFS), disease-specific-survival (DSS) based on this sub-staging system.

RESULTS

Pathological evaluation regarding the MM-VP invasion revealed 53 patients (57%) as pT1a BUC and 40 patients (43%) as pT1b BUC. The mean follow-up was 78.8 months. During the follow-up period; 60 patients (64.5%) had tumor recurrences, 32 patients (34.4%) had progression to invasive disease, 18 patients (19.4 %) died during follow-up related to the BUC. In 29 (54.7%) of pT1a and in 31(77.5%) of pT1b tumors, the recurrent disease was recorded during the followup period (p = 0.023). DSS rates at 5 years for pT1a and pT1b were 80.2% and 60.8%, respectively. PFS, RFS, and DSS rates were similar for pT1a/pT1b and did not reach statistical significance (p > 0.05).

CONCLUSIONS

Sub-staging of pT1 BUC according to the MM-VP invasion showed a limited impact on the outcome in our patient cohort. However, the presence of pT1b disease caused a significantly higher rate of recurrence.

Endoscopic Molecular Imaging plus Photoimmunotherapy: A New Strategy for Monitoring and Treatment of Bladder Cancer

Due to the high recurrence and progression rate of non-muscle invasive bladder cancer after transurethral resection of bladder tumor, some new optical imaging technologies have arisen as auxiliary imaging modes for white light cystoscopy to improve the detection rate of small or occult tumor lesions, such as photodynamic diagnosis, narrow-band imaging, and molecular imaging. White light cystoscopy is inadequate and imperfect for bladder cancer detection, and thus residual tumors or coexisting flat malignant lesions, especially carcinoma in situ, would be ignored during conventional resection. The bladder, a hollow organ with high compliance, provides an ideal closed operation darkroom for endoscopic molecular imaging free from interference of external light sources. Also, intravesical instillation of a molecular fluorescent tracer is simple and convenient before surgery through the urethra. Molecular fluorescent tracer has high sensitivity and specificity to tumor cells, and its mediated molecular imaging allows small or occult tumor lesion detection while minimizing false-positive results. Meanwhile, endoscopic molecular imaging provides a real-time and dynamic image during surgery, which helps urologists to perform high-quality and complete tumor resection through accurate judgment of tumor boundaries and depth of invasion. Photoimmunotherapy is a novel molecular targeted therapeutic pattern of photodynamic therapy that kills malignant cells selectively and minimizes the cytotoxicity to normal tissues. The combination of endoscopic molecular imaging and photoimmunotherapy used in initial treatment may avoid the need of repeat transurethral resection in strictly selected patients and improve oncological outcomes such as recurrence-free survival and overall survival after operation.

Quality Indicators for Bladder Cancer Services: A Collaborative Review

CONTEXT

There is a lack of accepted consensus on what should constitute appropriate quality-of-care indicators for bladder cancer.

OBJECTIVE

To evaluate the optimal management of bladder cancer and propose quality indicators (QIs).

EVIDENCE ACQUISITION

A systematic review was performed to identify literature on current optimal management and potential quality indicators for both non-muscle-invasive (NMIBC) and muscle-invasive (MIBC) bladder cancer. A panel of experts was convened to select a recommended list of QIs.

EVIDENCE SYNTHESIS

For NMIBC, preoperative QIs include tobacco cessation counselling and appropriate imaging before initial transurethral resection of bladder tumour (TURBT). Intraoperative QIs include administration of antibiotics, proper safe conduct of TURBT using a checklist, and performing restaging TURBT with biopsy of the prostatic urethra in appropriate cases. Postoperative QIs include appropriate receipt of perioperative adjuvant therapy, risk-stratified surveillance, and appropriate decision to change therapy when indicated (eg, bacillus Calmette-Guerin [BCG] unresponsive). For MIBC, preoperative QIs include multidisciplinary care, selection for candidates for continent urinary diversion, receipt of neoadjuvant cisplatin-based chemotherapy, time to commencing radical treatment, consideration of trimodal therapy as a bladder-sparing alternative in select patients, preoperative counselling with stoma marking, surgical volume of radical cystectomy, and enhanced recovery after surgery protocols. Intraoperative QIs include adequacy of lymphadenectomy, blood loss, and operative time. Postoperative QIs include prospective standardised monitoring of morbidity and mortality, negative surgical margins for pT2 disease, appropriate surveillance after primary treatment, and adjuvant cisplatin-based chemotherapy in appropriate cases. Participation in clinical trials was highlighted as an important component indicating high quality of care.

CONCLUSIONS

We propose a set of QIs for both NMIBC and MIBC based on established clinical guidelines and the available literature. Although there is currently a lack of level 1 evidence for the benefit of implementing these QIs, we believe that the measurement of these QIs could aid in the improvement and benchmarking of optimal care for bladder cancer.

PATIENT SUMMARY

After a systematic review of existing guidelines and literature, a panel of experts has recommended a set of quality indicators that can help providers and patients measure and strive towards optimal outcomes for bladder cancer care.

Overview of VI-RADS in Bladder Cancer

OBJECTIVE. The purpose of this article is to review the natural history and management of bladder cancer, with insight into MRI applications for the assessment of muscle invasiveness of bladder cancer using the newly developed Vesical Imaging Reporting and Data System (VI-RADS) score. CONCLUSION. Multiparametric MRI and the VI-RADS score have been consistently validated across several different institutions as appropriate tools for local staging of bladder cancer and have been proven to contribute to the diagnostic workup and management of urinary bladder cancer.

Use of Vesical Imaging-Reporting and Data System (VI-RADS) for detecting the muscle invasion of bladder cancer: a diagnostic meta-analysis

OBJECTIVES

To comprehensively assess the diagnostic performance of Vesical Imaging-Reporting and Data System (VI-RADS) score for detecting the muscle invasion of bladder cancer.

METHODS

PubMed, Web of Science, and Embase were searched up to November 20, 2019. QUADAS-2 tool assessed the quality of included studies. The diagnostic estimates including sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and the area under the curve (AUC) of hierarchical summary receiver operating characteristic (HSROC) were calculated. Further subgroup analysis, meta-regression and sensitivity analysis were conducted.

RESULTS

Six studies with 1064 patients were finally included. The pooled sensitivity, specificity, and AUC value were 0.90 (95% CI 0.86-0.94), 0.86 (95% CI 0.71-0.94), and 0.93 (95% CI 0.91-0.95) for VI-RADS 3 as the cutoff value. The corresponding estimates were 0.77 (95% CI 0.65-0.86), 0.97 (95% CI 0.88-0.99), and 0.92 (95% CI 0.89-0.94) for VI-RADS 4 as the cutoff value. Meta-regression analysis revealed that study design (p value 0.01) and surgical pattern of reference standard (p value 0.02) were source of the heterogeneity of pooled sensitivity. No publication bias was observed.

CONCLUSIONS

The VI-RADS score can provide a good predictive ability for detecting the muscle invasiveness of primary bladder cancer with VI-RADS 3 or VI-RADS 4 as the cutoff value.

KEY POINTS

• VI-RADS score has high sensitivity and specificity for predicting muscle invasion. • The diagnostic efficiencies of VI-RADS 3 and VI-RADS 4 as the cutoff value are similar. • VI-RADS score could be used for detecting muscle invasion of bladder cancer in clinical practice.

Repeat transurethral resection is still an essential tool in treating non-muscle invasive bladder cancer: the Western Australian experience

OBJECTIVES

To determine the rate of residual disease and under-staging after primary transurethral resection (TUR) of bladder tumors (TURBT) in tertiary hospitals in Western Australia.

METHODS

A retrospective study was performed evaluating all patients with TaHG (stage Ta, high-grade), T1LG (stage T1, low-grade) or T1HG (stage T1, high-grade) bladder cancer on primary TURBT conducted between January 1, 2012 and December 31, 2017 at the four largest metropolitan public hospitals in Western Australia. Only patients who underwent repeat resection within 3 months from initial resection were included. Those with previous history of bladder cancer, incomplete follow-up data and visibly incomplete initial resection were excluded. Baseline patient demographics, macroscopic clearance at initial resection, and disease data at initial and repeat resections were recorded.

RESULTS

Sixty-seven patients with a median age of 71 years were included in this study. At initial resection, T1HG was the most common disease stage (64.2%) and detrusor muscle was present in 82.1% of initial resections. At repeat resection, 41.8% of cases had residual disease. The rate of upstaging to muscle-invasive bladder cancer was 3.0%. Patients treated by operators with five or less years of formal training did not have a significantly different rate of residual disease from patients treated by operators with more than five years of experience.

CONCLUSIONS

Repeat TUR should remain an essential practice due to high rates of residual disease and a small risk of tumor under-staging. The presence of detrusor muscle and macroscopic clearance should not be used as surrogates for adequacy of resection or consideration of avoiding a repeat TUR, even for TaHG disease.