Quantifying the Overall Survival Benefit With Early Radical Cystectomy for Patients With Histologically Confirmed T1 Non-muscle-invasive Bladder Cancer

Combination intravesical chemotherapy for non-muscle invasive bladder cancer (NMIBC) as first-line or rescue therapy: where do we stand now?

INTRODUCTION

The combination of intravesical gemcitabine (Gem) with docetaxel (Doce) or with mitomycin C (MMC) has been used in the primary setting as an alternative to Bacillus Calmette-Guerin (BCG) to treat high-risk (HR) and intermediate-risk (IR) non-muscle invasive bladder cancer (NMIBC), as well in the rescue setting for patients in whom BCG has failed.

AREA COVERED

Efficacy and safety of Gem/Doce and Gem/MMC to treat NMIBC in BCG-naive and failure settings.

EXPERT OPINION

In the BCG-naive setting, Gem/Doce was the primary alternative combination therapy reported, with a weighted mean of 12- and 24-month recurrence-free survival (RFS) of 79% and 77% for HR disease and 84% and 76% for IR disease, respectively. In the HR BCG-failure setting, the weighted mean of 12- and 24-month RFS was 60% and 42% for Gem/Doce and 63% and 40% for Gem/MMC. While patients without BCG exposure and papillary disease only benefit the most from Gem/Doce, there is also reasonable efficacy in BCG refractory disease and CIS. Combination therapy is well tolerated, with grade III toxicity reported in less than 1% of patients. Unlike single-agent chemotherapy, intravesical Gem/Doce is considered effective and safe regardless of risk-stratification.

Diminished Short-Term Efficacy of Reduced-Dose Induction BCG in the Treatment of Non-Muscle Invasive Bladder Cancer

The ongoing Bacillus Calmette-Guérin (BCG) shortage has created challenges for the treatment of non-muscle invasive bladder cancer (NMIBCa). Our objective was to evaluate the efficacy of reduced-dose induction BCG (RD-iBCG) compared to full-dose induction BCG (FD-iBCG) regarding recurrence rates. We hypothesized that patients receiving RD-iBCG may recur at a higher rate compared to those who received FD-iBCG therapy. A retrospective review of all patients with NMIBCa treated with intravesical therapy at our institution between 2015-2020 was conducted. Inclusion criteria consisted of having a diagnosis of AUA intermediate or high-risk NMIBCa with an indication for a six-week induction course of FD or RD-BCG with at least 1 year of documented follow up. The data were censored at one year. Propensity score matching for age, sex, tumor pathology, and initial vs. recurrent disease was performed. The primary endpoint was bladder cancer recurrence, reported as recurrence-free survival. A total of 254 patients were reviewed for this study. Our final cohort was 139 patients after exclusion. Thirty-nine percent of patients had HGT1 disease. 38.6% of patients receiving RD-BCG developed a recurrence of bladder cancer within a one-year follow-up as compared to 33.7% of patients receiving FD therapy. After propensity matching, this value remained statistically significant (p = 0.03). In conclusion, RD-iBCG for NMIBCa is associated with a significantly greater risk of recurrence than full-dose induction therapy, suggesting that RD-iBCG may not be equivalent or non-inferior to full-dose administration in the short term.

CD8+ Cell Density Gradient across the Tumor Epithelium-Stromal Interface of Non-Muscle Invasive Papillary Urothelial Carcinoma Predicts Recurrence-Free Survival after BCG Immunotherapy

BACKGROUND

Bacille Calmette-Guerin (BCG) immunotherapy is the first-line treatment in patients with high-risk non-muscle invasive papillary urothelial carcinoma (NMIPUC), the most common type of bladder cancer. The therapy outcomes are variable and may depend on the immune response within the tumor microenvironment. In our study, we explored the prognostic value of CD8+ cell density gradient indicators across the tumor epithelium-stroma interface of NMIPUC.

METHODS

Clinical and pathologic data were retrospectively collected from 157 NMIPUC patients treated with BCG immunotherapy after transurethral resection. Whole-slide digital image analysis of CD8 immunohistochemistry slides was used for tissue segmentation, CD8+ cell quantification, and the assessment of CD8+ cell densities within the epithelium-stroma interface. Subsequently, the gradient indicators (center of mass and immunodrop) were computed to represent the density gradient across the interface.

RESULTS

By univariable analysis of the clinicopathologic factors, including the history of previous NMIPUC, poor tumor differentiation, and pT1 stage, were associated with shorter RFS (p < 0.05). In CD8+ analyses, only the gradient indicators but not the absolute CD8+ densities were predictive for RFS (p < 0.05). The best-performing cross-validated model included previous episodes of NMIPUC (HR = 4.4492, p = 0.0063), poor differentiation (HR = 2.3672, p = 0.0457), and immunodrop (HR = 5.5072, p = 0.0455).

CONCLUSIONS

We found that gradient indicators of CD8+ cell densities across the tumor epithelium-stroma interface, along with routine clinical and pathology data, improve the prediction of RFS in NMIPUC.

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.

Impact of carcinoma in situ on the outcome of intravesical Bacillus Calmette-Guérin therapy for non-muscle-invasive bladder cancer: a comparative analysis of large real-world data

BACKGROUND

This study investigated the clinical impact of carcinoma in situ (CIS) in intravesical Bacillus Calmette-Guérin (BCG) therapy for patients with non-muscle-invasive bladder cancer (NMIBC).

METHODS

This study retrospectively evaluated 3035 patients who were diagnosed with NMIBC and treated by intravesical BCG therapy between 2000 and 2019 at 31 institutions. Patients were divided into six groups according to the presence of CIS as follows: low-grade Ta without concomitant CIS, high-grade Ta without concomitant CIS, high-grade Ta with concomitant CIS, high-grade T1 without concomitant CIS, high-grade T1 with concomitant CIS, and pure CIS (without any papillary lesion). The endpoints were recurrence- and progression-free survival after the initiation of BCG therapy. We analyzed to identify factors associated with recurrence and progression.

RESULTS

At a median follow-up of 44.4 months, recurrence and progression were observed in 955 (31.5%) and 316 (10.4%) patients, respectively. Comparison of six groups using univariate and multivariate analysis showed no significant association of CIS. However, CIS in the prostatic urethra was an independent factors associated with progression.

CONCLUSION

Concomitant CIS did not show a significant impact in the analysis of Ta and T1 tumors which were treated using intravesical BCG. Concomitant CIS in the prostatic urethra was associated with high risk of progression. Alternative treatment approaches such as radical cystectomy should be considered for patients with NMIBC who have a risk of progression.

Adjuvant therapies for non-muscle-invasive bladder cancer: advances during BCG shortage

Non-muscle-invasive bladder cancer (NMIBC) represents a significant global therapeutic challenge, particularly in the era of Bacillus Calmette-Guérin (BCG) shortage. High-risk NMIBC can progress to muscle invasive or metastatic disease in 25% of patients. Optimal treatment selection, according to risk stratification, is imperative. International guidelines slightly differ in their categorisation of low, intermediate and high-risk NMIBC. Nonetheless, a single post-operative instillation of chemotherapy with Mitomycin C (MMC) or Gemcitabine improves relapse-free survival (RFS) in low-risk NMIBC. Induction and maintenance intravesical BCG remains the historical gold standard for patients with intermediate or high-risk NMIBC. However, clinicians may be forced to consider alternatives given the current BCG shortage. Both intravesical MMC and Gemcitabine have been associated with similar efficacy to BCG, albeit in smaller studies. MMC may also be manipulated using a variety of methods to potentiate its effects. BCG treatment delivery may also be modified without affecting efficacy through dose reduction and abbreviation or omission of maintenance therapy. Preliminary data also highlight that directly proceeding to radical cystectomy may not adversely affect long-term quality of life measures. Access to new systemic and intravesical therapies must be prioritised for patients with BCG recurrent or unresponsive disease. When used in conjunction with molecularly defined biomarkers, these agents herald the potential for improved survival outcomes and alleviation of the current BCG shortage.

Treatment Outcomes of High-Risk Non-Muscle Invasive Bladder Cancer (HR-NMIBC) in Real-World Evidence (RWE) Studies: Systematic Literature Review (SLR)

Background

To date, there has been limited synthesis of RWE studies in high-risk non-muscle invasive bladder cancer (HR-NMIBC). The objective of this research was to conduct a systematic review of published real-world evidence to better understand the real-world burden and treatment patterns in HR-NMIBC.

Methods

An SLR was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines with the scope defined by the Population, Intervention Comparators, Outcomes, and Study design (PICOS) criteria. EMBASE, MEDLINE, and Cochrane databases (Jan 2015–Jul 2020) were searched, and relevant congress abstracts (Jan 2018–Jul 2020) identified. The final analysis only included studies that enrolled ≥100 patients with HR-NMIBC from the US, Europe, Canada, and Australia.

Results

The SLR identified 634 RWE publications in NMIBC, of which 160 studies reported data in HR-NMIBC. The average age of patients in the studies was 71 years, and 79% were males. The rates of BCG intravesical instillations ranged from 3% to 86% (29–95% for induction and 8–83% for maintenance treatment). Five-year outcomes were 17–89% recurrence-free survival (longest survival in patients completing BCG maintenance), 58–89% progression-free survival, 71–96% cancer-specific survival (lowest survival in BCG-unresponsive patients), and 28–90% overall survival (lowest survival in patients who did not receive BCG or instillation therapy).

Conclusion

BCG treatment rates and survival outcomes in patients with HR-NMIBC vary in the real world, with better survival seen in patients completing maintenance BCG, responding to treatment, and not progressing to muscle-invasive disease. There is a need to better understand the factors associated with BCG use and discontinuation and for an effective treatment that improves outcomes in HR-NMIBC. Generalization of these results is limited by variations in data collection, reporting, and methodologies used across RWE studies.