Outcomes of bacillus Calmette-Guérin therapy without a maintenance schedule for high-risk non-muscle-invasive bladder cancer in the second transurethral resection era

Gender-Specific Differences in Recurrence and Progression following Bacillus Calmette-Guérin Instillation for Non-Muscle-Invasive Bladder Cancer

INTRODUCTION

To assess gender-specific differences in recurrence-free survival (RFS), progression-free survival (PFS), cancer-specific survival (CSS), and overall survival (OS) among patients with intermediate or high-risk non-muscle-invasive bladder cancer (NMIBC) receiving BCG was the primary aim of this systematic review and meta-analysis.

METHODS

In July 2023, we performed a literature search using MEDLINE, Embase, and the Cochrane Library. This study was prospectively registered at PROSPERO (CRD 2023443269). The detailed review protocol is accessible via CRD.

RESULTS

The systematic literature search identified 6,723 studies, of which 38 fulfilled the inclusion criteria. Random-effect meta-analysis for RFS, based on data from 24 studies, revealed no statistically significant gender-specific difference (HR comparing males to females = 0.9618, 95% CI: 0.8408-1.1003, p = 0.5707). Similarly, for PFS, incorporating data from 14 studies, no statistically significant difference (HR = 0.9540, 95% CI: 0.7709-1.1805, p = 0.6648), for CSS, analysis of data from three studies yielded no statistically significant difference (HR = 0.9228, 95% CI: 0.6196-1.3743, p = 0.6925), and for OS, based on data from two studies, no statistically significant difference was observed (HR = 1.1436, 95% CI: 0.5092-2.5684, p = 0.7452). The risk of bias assessment indicated an overall moderate to high risk of bias.

CONCLUSION

The findings indicate no association between gender and oncologic outcomes following BCG.

The impact of second transurethral resection on survival outcomes in patients with non-muscle-invasive bladder cancer treated with bacillus Calmette-Guérin therapy

OBJECTIVE

Several guidelines recommended that second transurethral resection should be performed in patients with diagnosis of high-risk non-muscle-invasive bladder cancer. However, therapeutic benefits of second transurethral resection before bacillus Calmette-Guérin intravesical instillation were conflicting amongst previous studies. We investigated the prognostic impact of second transurethral resection before bacillus Calmette-Guérin instillation in high-risk non-muscle-invasive bladder cancer patients.

METHODS

This retrospective study included 3104 non-muscle-invasive bladder cancer patients who received bacillus Calmette-Guérin instillations between 2000 and 2019 at 31 collaborative institutions. Univariate and multivariate Cox proportional hazards models were used to assess the risk factors of intravesical recurrence, disease progression, cancer-specific mortality and overall mortality.

RESULTS

In the entire population, patients undergoing second transurethral resection (33%, 1026/3104) had a lower risk of intravesical recurrence on univariate analysis (hazard ratio 0.85, 95% confidence interval 0.73-0.98, P = 0.027), although it did not remain significant on multivariate analysis (hazard ratio 0.90, 95% confidence interval 0.76-1.07, P = 0.24). Subgroup analysis revealed that, in pT1 patients (n = 1487), second transurethral resection was significantly correlated with a lower risk of intravesical recurrence on multivariate analysis (hazard ratio 0.80, 95% confidence interval 0.64-1.00, P = 0.048), but lower risks of disease progression (hazard ratio 0.75, 95% confidence interval 0.56-1.00, P = 0.049), cancer-specific mortality (hazard ratio 0.54, 95% confidence interval 0.35-0.85, P = 0.007) and overall mortality (hazard ratio 0.73, 95% confidence interval 0.55-0.97, P = 0.027) on univariate analysis.

CONCLUSIONS

Second transurethral resection confers accurate pathological staging and could be used to safely select good candidates for intravesical bacillus Calmette-Guérin instillation. We further confirm that second transurethral resection could confer an oncological benefit in pT1 bladder cancer patients treated by bacillus Calmette-Guérin instillation, and so strongly recommend second transurethral resection in this patient population.

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.

Intermediate and high-risk non-muscle-invasive bladder cancer: an overview of epidemiology, burden, and unmet needs

Bladder cancer ranks among the most common cancers globally. At diagnosis, 75% of patients have non-muscle-invasive bladder cancer (NMIBC). Patients with low-risk NMIBC have a good prognosis, but recurrence and progression rates remain high in intermediate- and high-risk NMIBC, despite the decades-long availability of effective treatments for NMIBC such as intravesical Bacillus Calmette-Guérin (BCG). The present review provides an overview of NMIBC, including its burden and treatment options, and then reviews aspects that counteract the successful treatment of NMIBC, referred to as unmet treatment needs. The scale and reasons for each unmet need are described based on a comprehensive review of the literature, including insufficient adherence to treatment guidelines by physicians because of insufficient knowledge, training, or access to certain therapy options. Low rates of lifestyle changes and treatment completion by patients, due to BCG shortages or toxicities and adverse events as well as their impact on social activities, represent additional areas of potential improvement. Highly heterogeneous evidence for the effectiveness and safety of some treatments limits the comparability of results across studies. As a result, efforts are underway to standardize treatment schedules for BCG, but intravesical chemotherapy schedules remain unstandardized. In addition, risk-scoring models often perform unsatisfactorily due to significant differences between derivation and real-world cohorts. Reporting in clinical trials suffers from a lack of consistent outcomes reporting in bladder cancer clinical trials, paired with an under-representation of racial and ethnic minorities in many trials.

Single immediate instillation of chemotherapy is associated with decreased recurrence and progression in patients with high-risk non-muscle-invasive bladder cancer who receive adjuvant induction bacillus Calmette-Guérin therapy

OBJECTIVES

To investigate whether a single intravesical instillation of chemotherapy is associated with improved oncological outcomes in patients with high-risk non-muscle-invasive bladder cancer who receive adjuvant induction bacillus Calmette-Guérin therapy.

METHODS

This multi-institutional retrospective study included 205 patients with high-risk non-muscle-invasive bladder cancer who received adjuvant induction bacillus Calmette-Guérin therapy. Patients were divided into two groups: those who received the combined therapy of a single instillation of chemotherapy plus subsequent adjuvant induction bacillus Calmette-Guérin therapy (combined therapy group), and those who received adjuvant induction bacillus Calmette-Guérin therapy alone (bacillus Calmette-Guérin monotherapy group). Multivariable analyses using the inverse probability of treatment weighting method and Fine-Gray competing risk regression models were performed to evaluate the impact of a single instillation of chemotherapy on intravesical recurrence-free survival and muscle-invasive bladder cancer-free survival.

RESULTS

Among the 205 patients, 130 (63%) and 75 (37%) were classified as the combined therapy and bacillus Calmette-Guérin monotherapy groups, respectively. Multivariable analyses using the inverse probability of treatment weighting method showed that a single instillation of chemotherapy was significantly associated with longer intravesical recurrence-free survival (hazard ratio 0.279; P < 0.001) and muscle-invasive bladder cancer-free survival (hazard ratio 0.078; P < 0.001). Fine-Gray competing risk regression model revealed that a single instillation of chemotherapy was associated with a significantly lower probability of intravesical recurrence and muscle-invasive bladder cancer progression, with an adjusted subdistribution hazard ratio of 0.477 (P = 0.008) and 0.261 (P = 0.043), respectively.

CONCLUSION

A single intravesical instillation of chemotherapy may be a potential treatment option in patients with high-risk non-muscle-invasive bladder cancer who receive adjuvant induction bacillus Calmette-Guérin therapy.