Quinolone Prophylaxis in Conjunction with Bacillus Calmette-Guérin Instillations for Bladder Cancer: Time To Reconsider the Evidence and Open the Quinolone Box?

Long-term Oncological Outcomes for Patients with Non-muscle-invasive Bladder Cancer Treated with Bacillus Calmette-Guérin (BCG): A Comparative Analysis of Adequate Versus Inadequate BCG Treatment

BACKGROUND AND OBJECTIVE

Intravesical bacillus Calmette-Guérin (BCG) instillation is recommended for intermediate-risk (IR) and high-risk (HiR) non-muscle-invasive bladder cancer (NMIBC). There are limited comparisons of long-term outcomes between adequate and inadequate BCG.

METHODS

We analyzed data from a multicenter European database (2010-2024) for 1558 patients diagnosed with IR- or HiR-NMIBC who underwent BCG treatment and received at least five BCG instillations. Adequate BCG was defined as at least five of six induction instillations and two of three maintenance doses, or two of six doses of a reinduction course. A 3-mo landmark analysis was conducted. Recurrence-free survival (RFS), high-grade RFS (HG-RFS), progression-free survival (PFS), and overall survival (OS) were estimated using inverse probability of treatment weighting (IPTW)-adjusted Kaplan-Meier curves and IPTW-adjusted multivariable Cox regression models. Cancer-specific mortality (CSM) was assessed via cumulative incidence curves and Fine-Gray competing-risks regression analysis.

KEY FINDINGS AND LIMITATIONS

The cohort included 606 IR-NMIBC (39%), 840 HiR-NMIBC (54%), and 112 very HiR (VHR)-NMIBC (7.1%) cases. Adequate BCG was administered to 1226 patients (78%). Among 1239 patients (80%) with documented treatment termination reasons, 503 (41%) completed guideline-recommended treatment and 150 (12%) discontinued because of BCG intolerance. Over median follow-up of 37 mo, adequate BCG was associated with higher IPTW-adjusted 5-yr RFS (72% vs 52%; hazard ratio [HR] 0.40, 95% confidence interval [CI] 0.31-0.85; p < 0.001), HG-RFS (83% vs 68%; HR 0.43, 95% CI 0.32-0.58; p < 0.001), PFS (92% vs 85%; HR 0.47, 95% CI 0.30-0.74; p = 0.001), and OS (88% vs 71%; HR 0.52, 95% CI 0.37-0.74; p = 0.001). CSM rates were comparable between the groups (3% vs 4.9%; p = 0.3).

CONCLUSIONS AND CLINICAL IMPLICATIONS

Adequate BCG, as defined by the International Bladder Cancer Group (IBCG), was associated with significantly better RFS, PFS, and OS. These findings support use of the IBCG definition as a standardized benchmark for BCG exposure. However, further prospective validation to confirm causality is needed.

Oncological Outcomes in Bacillus Calmette-Guérin-naïve High-risk Non-muscle-invasive Bladder Cancer Patients: A Systematic Review on Current Treatment Strategies and Future Perspectives

BACKGROUND AND OBJECTIVE

Bacillus Calmette-Guérin (BCG) is the standard treatment in patients harboring high-risk (HR) non-muscle-invasive bladder cancer (NMIBC). However, BCG therapy faces frequent adverse events (AEs), limited efficacy, and ongoing shortages, leading to a low completion rate, access challenges, and high recurrence. In consequence, there is a growing interest in exploring alternative treatments, including immune checkpoint inhibitors, chemotherapy combinations, and novel intravesical therapies. This systematic review summarizes current prospective evidence on BCG and alternative treatment options for BCG-naïve HR-NMIBC patients (PROSPERO: CRD42024564900).

METHODS

A systematic search in MEDLINE, EMBASE, Scopus, Web of Science, and Cochrane Library retrieved 1042 studies, of which 17 met the inclusion criteria (following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines).

KEY FINDINGS AND LIMITATIONS

In 12 studies on BCG-treated patients (n = 1418), recurrence-free survival (RFS) rates were 66-96% at 1-yr, 63-96% at 2-yr, and 39-66% at 5-yr follow-up. Progression-free survival (PFS) rates were 81-98% at 1-yr, 70-96% at 2-yr, and 70-84% at 5-yr follow-up. In nine studies focusing on patients treated with alternative strategies (n = 657), RFS rates were 51-99% at 1-yr, 48-88% at 2-yr, and 47-55% at 5-yr follow-up. PFS was 90-100% at 1-yr, 88-96% at 2-yr, and 84-93% at 5-yr follow-up. AE rates varied widely across studies, for both BCG and alternative treatments. Unfortunately, studies heterogeneity and a small sample sizes limit statistically meaningful conclusions. Twelve clinical trials are currently investigating new strategies for BCG-naïve HR NMIBC patients.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Alternative therapies for BCG-naïve HR NMIBC patients are emerging but need further validation. As challenges such as toxicity, cost, and long-term efficacy persist, ongoing trial results will be crucial in determining their role in future clinical practice.

Analysis of local and systemic side effects of bacillus Calmette-Guérin immunotherapy in bladder cancer: a retrospective study in Türkiye

Background

Bladder cancer is a growing health concern, especially in developing countries like Türkiye. Intravesical Bacillus Calmette-Guérin (BCG) immunotherapy is essential for reducing recurrence and progression in non-muscle invasive bladder cancer (NMIBC). However, it can cause local and systemic adverse effects linked to bacterial virulence, allergic reactions, or nosocomial infections. Data from randomized studies on BCG side effects are limited, with severe cases often reported in case studies. This study investigates the association between intravesical BCG immunotherapy and its adverse effects.

Methods

A retrospective analysis was conducted on 239 patients who underwent BCG immunotherapy between 2017 and 2024. Detailed demographic, clinical, and laboratory data were collected, and the adverse effects that developed following BCG therapy were evaluated. Descriptive statistics, including medians, counts, and percentage distributions, were calculated, and logistic regression analysis was performed to identify factors influencing the development of adverse effects.

Results

Adverse effects related to BCG immunotherapy were observed in 63.1% of the patients. The most common minor adverse effects were hematuria, dysuria, and cystitis, while major adverse effects included sepsis and lymphadenopathy. The analyses revealed that elevated aspartate aminotransferase (AST) levels and the presence of Escherichia coli and Enterococcus faecalis in urine cultures were significant risk factors for the development of adverse effects. Additionally, patients who underwent the 6th cycle of BCG therapy were found to have a higher risk of developing adverse effects compared to those who received fewer cycles.

Conclusion

BCG immunotherapy is an effective treatment method for NMIBC; however, the adverse effects that occur during treatment must be closely monitored. Elevated AST levels, the presence of specific pathogens in urine cultures, and the number of BCG doses administered are significant factors that increase the risk of adverse effects. These findings highlight the necessity for more careful monitoring throughout the treatment process.

Multiparametric MRI and artificial intelligence in predicting and monitoring treatment response in bladder cancer

Bladder cancer is the 10th most common and 13th most deadly cancer worldwide, with urothelial carcinomas being the most common type. Distinguishing between non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC) is essential due to significant differences in management and prognosis. MRI may play an important diagnostic role in this setting. The Vesical Imaging Reporting and Data System (VI-RADS), a multiparametric MRI (mpMRI)-based consensus reporting platform, allows for standardized preoperative muscle invasion assessment in BCa with proven diagnostic accuracy. However, post-treatment assessment using VI-RADS is challenging because of anatomical changes, especially in the interpretation of the muscle layer. MRI techniques that provide tumor tissue physiological information, including diffusion-weighted (DW)- and dynamic contrast-enhanced (DCE)-MRI, combined with derived quantitative imaging biomarkers (QIBs), may potentially overcome the limitations of BCa evaluation when predominantly focusing on anatomic changes at MRI, particularly in the therapy response setting. Delta-radiomics, which encompasses the assessment of changes (Δ) in image features extracted from mpMRI data, has the potential to monitor treatment response. In comparison to the current Response Evaluation Criteria in Solid Tumors (RECIST), QIBs and mpMRI-based radiomics, in combination with artificial intelligence (AI)-based image analysis, may potentially allow for earlier identification of therapy-induced tumor changes. This review provides an update on the potential of QIBs and mpMRI-based radiomics and discusses the future applications of AI in BCa management, particularly in assessing treatment response. CRITICAL RELEVANCE STATEMENT: Incorporating mpMRI-based quantitative imaging biomarkers, radiomics, and artificial intelligence into bladder cancer management has the potential to enhance treatment response assessment and prognosis prediction. KEY POINTS: Quantitative imaging biomarkers (QIBs) from mpMRI and radiomics can outperform RECIST for bladder cancer treatments. AI improves mpMRI segmentation and enhances radiomics feature extraction effectively. Predictive models integrate imaging biomarkers and clinical data using AI tools. Multicenter studies with strict criteria validate radiomics and QIBs clinically. Consistent mpMRI and AI applications need reliable validation in clinical practice.

Revolutionizing Treatment: Breakthrough Approaches for BCG-Unresponsive Non-Muscle-Invasive Bladder Cancer

Bladder cancer is the 10th most popular cancer in the world, and non-muscle-invasive bladder cancer (NMIBC) is diagnosed in ~80% of all cases. Treatments for NMIBC include transurethral resection of the bladder tumor (TURBT) and intravesical instillations of Bacillus Calmette-Guérin (BCG). Treatment of BCG-unresponsive tumors is scarce and usually leads to Radical Cystectomy. In this paper, we review recent advancements in conservative treatment of BCG-unresponsive tumors. The main focus of the paper is FDA-approved medications: Pembrolizumab and Nadofaragene Firadenovec (Adstiladrin). Other, less researched therapeutic possibilities are also included, namely: N-803 immunotherapy, TAR-200 and TAR-210 intravesical delivery systems and combined Cabazitaxel, Gemcitabine and Cisplatin chemotherapy. Conservative treatment and delaying radical cystectomy would greatly benefit patients' quality of life; it is undoubtedly the future of BCG-unresponsive NMIBC.