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

Comparison of staging MRI to re-resection for localised bladder cancer: Narrative review

Introduction

Bladder cancer (BCa) is characterised by high prevalence, multifocality, and frequent recurrence, imposing significant clinical and economic burdens. Accurate staging, particularly distinguishing non-muscle-invasive bladder cancer (NMIBC) from muscle-invasive bladder cancer (MIBC) disease, is crucial for guiding treatment decisions. This narrative review explores the potential implications of incorporating multiparametric magnetic resonance imaging (mpMRI) and the Vesical Imaging Reporting Data System (VI-RADS) into BCa staging, focusing on repeat transurethral resection of bladder tumour (re-TURBT).

Methods

A comprehensive search of PubMed, EMBASE, and MEDLINE databases identified studies published from 2018 to 2023 discussing mpMRI or VI-RADS in the context of re-TURBT for BCa staging. Studies meeting inclusion criteria underwent qualitative analysis.

Results

Six recent studies met inclusion criteria. VI-RADS scoring, accurately predicted muscle invasion, aiding in NMIBC/MIBC differentiation. VI-RADS scores of ≥3 indicated MIBC with high sensitivity and specificity. VI-RADS potentially identified patients benefiting from re-TURBT and those for whom it could be safely omitted.

Discussion

mpMRI and VI-RADS offer promising prospects for BCa staging, potentially correlating more closely with re-TURBT and radical cystectomy histopathology than initial TURBT. However, validation and careful evaluation of clinical integration are needed. Future research should refine patient selection and optimise mpMRI's role in BCa management.

Conclusion

VI-RADS scoring could revolutionise BCa staging, especially regarding re-TURBT. There is potential that VI-RADS correlates more with the histopathology of re-TURBT and radical cystectomy than initial TURBT. While promising, ongoing research is essential to validate utility, refine selection criteria, and address economic considerations. Integration of VI-RADS into BCa staging holds potential benefits for patients and health care systems.

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.

A Systematic Review on the Role of Repeat Transurethral Resection after Initial en Bloc Resection for Non-Muscle Invasive Bladder Cancer

International guidelines recommend repeat transurethral resection of bladder tumors (reTURB) for selected patients with high-risk non-muscle invasive bladder cancer to remove possible residual tumors, restage tumors and improve the therapeutic outcome. However, most evidence supporting the benefits of reTURB is from conventional TURB. The role of reTURB in patients receiving initial En bloc resection of bladder tumor (ERBT) is still unknown. PubMed, Embase, Web of Science, The Cochrane Library, and China National Knowledge Infrastructure (CNKI) were systematically searched. Finally, this systematic review and meta-analysis included twelve articles, including 539 patients. The rates of residual tumor and tumor upstaging detected by reTURB after ERBT were 5.9% (95%CI, 2.0%–11.1%) and 0.0% (95%CI, 0.0%–0.5%), respectively. Recurrence-free survival, tumor recurrence and progression were comparable between patients with and without reTURB after initial ERBT. The pooled hazard ratios of 1-year, 2-year, 3-year and 5-year recurrence-free survival were 0.74 (95%CI, 0.36–1.51; p = 0.40), 0.76 (95%CI, 0.45–1.26; p = 0.28), 0.83 (95%CI, 0.53–1.32; p = 0.43) and 0.83 (95%CI, 0.56–1.23; p = 0.36), respectively. The pooled relative risks of recurrence and progression were 0.87 (95%CI, 0.64–1.20; p = 0.40) and 1.11 (95%CI, 0.54–2.32; p = 0.77), respectively. Current evidence demonstrates that reTURB after ERBT for bladder cancer can detect relatively low rates of residual tumor and tumor upstaging and appears not to improve either recurrence or progression.

En bloc resection of bladder tumors: challenges and unmet needs in 2021

Non-muscle invasive bladder cancer accounts for the majority of new bladder cancer diagnoses, and endoscopic transurethral resection of bladder tumor (TURBT) represents the standard-of-care. Although a relatively safe and common procedure, TURBT is often hampered by the questionable quality of resection. The evolution of surgical techniques has brought en bloc resection of bladder tumor (ERBT) to the forefront. ERBT has emerged as an alternative to conventional TURBT, incorporating a more delicate en bloc sculpting and tumor excision, in contrast to 'piecemeal' resection by conventional TURBT. ERBT appears safe, feasible and effective with demonstrably higher rates of detrusor muscle in the pathologic specimen, all while providing better staging and obviating the need for a re-TURBT in selected patients. However, the method's adoption in the field is still limited. This review summarizes the recent evidence relevant to ERBT while further highlighting the technique's limitations and unmet needs.

Reduced Recurrence Rates Are Associated with Photodynamic Diagnostics Compared to White Light after Extended Transurethral Resection of Bladder Tumors

One pillar in treating non-muscle-invasive bladder cancer (NMIBC) is the complete and high-quality transurethral resection of the primary tumor (TURBT). However, even after a high-quality primary resection, the residual tumor risk is considerable, thus requiring a re-TURBT. Resections performed with the aid of a photodynamic diagnostics report improved recurrence-free survival rates and increased detection rates of carcinoma in situ (CIS). This monocentric retrospective study reports on patients treated with an extended TURBT procedure using conventional white-light cystoscopy or photodynamic diagnostics (PDD). Only patients undergoing a TURBT resection for their primary tumor were included in the statistical analysis. Recurrence-free survival and overall survival were the clinical endpoints. Mann−Whitney U tests and chi-squared tests were used for descriptive intergroup comparisons. The associations with overall survival and recurrence-free survival were determined by univariate and multivariate analyses. The test results were considered significant when p was < 0.05. In comparison to conventional white-light cystoscopy, PDD increased the detection rates of CIS (p = 0.004) and tumor multifocality (p = 0.005) and led to reduced residual tumor incidence at the primary resection site (p < 0.001). Likewise, tumor recurrence rates were reduced in the PDD cohort (p < 0.001). Patient age and the presence of residual tumor at the primary resection site were identified as independent predictors of overall survival. For recurrence-free survival, only the PDD resection method was an independent predictor (HR = 0.43; p < 0.001). In summary, we demonstrated that the utilization of PDD techniques was associated with improved detection rates of CIS and multifocal tumors and with reduced recurrence rates. The extended resection protocol allowed us to determine that PDD resections lead to a reduced residual tumor rate at the initial resection site. This residual tumor state at the resection site, determined by extended TURBT, became an independent predictor of long-term survival. On the other hand, the PDD technique was confirmed as the only independent predictor of recurrence-free survival.