Equivalent efficacy of mitomycin C plus doxorubicin instillation to bacillus Calmette-Guerin therapy for carcinoma in situ of the bladder

Efficacy of Different Bacillus of Calmette-Guérin (BCG) Strains on Recurrence Rates among Intermediate/High-Risk Non-Muscle Invasive Bladder Cancers (NMIBCs): Single-Arm Study Systematic Review, Cumulative and Network Meta-Analysis

BACKGROUND

In an era of Bacillus of Calmette-Guérin (BCG) shortages, the comparative efficacy from different adjuvant intravesical BCG strains in non-muscle invasive bladder cancer (NMIBC) has not been clearly elucidated. We aim to compare, through a systematic review and meta-analysis, the cumulative BC recurrence rates and the best efficacy profile of worldwide available BCG strains over the last forty years.

METHODS

PubMed, Scopus, Web of Science, Embase, and Cochrane databases were searched from 1982 up to 2022. A meta-analysis of pooled BC recurrence rates was stratified for studies with ≤3-y vs. >3-y recurrence-free survival (RFS) endpoints and the strain of BCG. Sensitivity analysis, sub-group analysis, and meta-regression were implemented to investigate the contribution of moderators to heterogeneity. A random-effect network meta-analysis was performed to compare BCG strains on a multi-treatment level.

RESULTS

In total, n = 62 series with n = 15,412 patients in n = 100 study arms and n = 10 different BCG strains were reviewed. BCG Tokyo 172 exhibited the lowest pooled BC recurrence rate among studies with ≤3-y RFS (0.22 (95%CI 0.16-0.28). No clinically relevant difference was noted among strains at >3-y RFS outcomes. Sub-group and meta-regression analyses highlighted the influence of NMIBC risk-group classification and previous intravesical treated categories. Out of the n = 11 studies with n = 7 BCG strains included in the network, BCG RIVM, Tice, and Tokyo 172 presented with the best-predicted probability for efficacy, yet no single strain was significantly superior to another in preventing BC recurrence risk.

CONCLUSION

We did not identify a BCG stain providing a clinically significant lower BC recurrence rate. While these findings might discourage investment in future head-to-head randomized comparison, we were, however, able to highlight some potential enhanced benefits from the genetically different BCG RIVM, Tice, and Tokyo 172. This evidence would support the use of such strains for future BCG trials in NMIBCs.

Intravesical Bacillus Calmette-Guérin versus mitomycin C for Ta and T1 bladder cancer

BACKGROUND

People with urothelial carcinoma of the bladder are at risk for recurrence and progression following transurethral resection of a bladder tumour (TURBT). Mitomycin C (MMC) and Bacillus Calmette-Guérin (BCG) are commonly used, competing forms of intravesical therapy for intermediate- or high-risk non-muscle invasive (Ta and T1) urothelial bladder cancer but their relative merits are somewhat uncertain.

OBJECTIVES

To assess the effects of BCG intravesical therapy compared to MMC intravesical therapy for treating intermediate- and high-risk Ta and T1 bladder cancer in adults.

SEARCH METHODS

We performed a systematic literature search in multiple databases (CENTRAL, MEDLINE, Embase, Web of Science, Scopus, LILACS), as well as in two clinical trial registries. We searched reference lists of relevant publications and abstract proceedings. We applied no language restrictions. The latest search was conducted in September 2019.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared intravesical BCG with intravesical MMC therapy for non-muscle invasive urothelial bladder cancer.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the literature, extracted data, assessed risk of bias and rated the quality of evidence according to GRADE per outcome. In the meta-analyses, we used the random-effects model.

MAIN RESULTS

We identified 12 RCTs comparing BCG versus MMC in participants with intermediate- and high-risk non-muscle invasive bladder tumours (published from 1995 to 2013). In total, 2932 participants were randomised. Time to death from any cause: BCG may make little or no difference on time to death from any cause compared to MMC (hazard ratio (HR) 0.97, 95% confidence interval (CI) 0.79 to 1.20; participants = 1132, studies = 5; 567 participants in the BCG arm and 565 in the MMC arm; low-certainty evidence). This corresponds to 6 fewer deaths (40 fewer to 36 more) per 1000 participants treated with BCG at five years. We downgraded the certainty of the evidence two levels due to study limitations and imprecision. Serious adverse effects: 12/577 participants treated with BCG experienced serious non-fatal adverse effects compared to 4/447 participants in the MMC group. The pooled risk ratio (RR) is 2.31 (95% CI 0.82 to 6.52; participants = 1024, studies = 5; low-certainty evidence). Therefore, BCG may increase the risk for serious adverse effects compared to MMC. This corresponds to nine more serious adverse effects (one fewer to 37 more) with BCG. We downgraded the certainty of the evidence two levels due to study limitations and imprecision. Time to recurrence: BCG may reduce the time to recurrence compared to MMC (HR 0.88, 95% CI 0.71 to 1.09; participants = 2616, studies = 11, 1273 participants in the BCG arm and 1343 in the MMC arm; low-certainty evidence). This corresponds to 41 fewer recurrences (104 fewer to 29 more) with BCG at five years. We downgraded the certainty of the evidence two levels due to study limitations, imprecision and inconsistency. Time to progression: BCG may make little or no difference on time to progression compared to MMC (HR 0.96, 95% CI 0.73 to 1.26; participants = 1622, studies = 6; 804 participants in the BCG arm and 818 in the MMC arm; low-certainty evidence). This corresponds to four fewer progressions (29 fewer to 27 more) with BCG at five years. We downgraded the certainty of the evidence two levels due to study limitations and imprecision. Quality of life: we found very limited data for this outcomes and were unable to estimate an effect size.

AUTHORS' CONCLUSIONS

Based on our findings, BCG may reduce the risk of recurrence over time although the Confidence Intervals include the possibility of no difference. It may have no effect on either the risk of progression or risk of death from any cause over time. BCG may cause more serious adverse events although the Confidence Intervals once again include the possibility of no difference. We were unable to determine the impact on quality of life. The certainty of the evidence was consistently low, due to concerns that include possible selection bias, performance bias, given the lack of blinding in these studies, and imprecision.

Investigational therapies for non-muscle invasive bladder cancer

IMPORTANCE OF THE FIELD

Bacillus Calmette-Guérin (BCG) is currently the most effective adjuvant intravesical agent at preventing disease recurrence and the only therapy shown to inhibit disease progression in non-muscle invasive bladder cancer (NMIBC). However, recurrence rates as high as 30% and significant local/systemic toxicity have resulted in an increased interest in the use of alternative intravesical agents.

AREAS COVERED IN THE REVIEW

Our aim is to discuss recent clinical trial evidence utilizing novel intravesical agents for treatment of NMIBC. A systematic literature review was performed via the National Center for Biotechnology Information databases to identify pertinent studies from 2000-2009.

WHAT THE READER WILL GAIN

A durable response has been demonstrated with alternative agents in patients refractory to or intolerant of BCG. This review compares the merits and shortcomings of these emerging agents, focusing on clinical trial safety and efficacy results.

TAKE HOME MESSAGE

Despite recent enthusiasm for novel agents, radical cystectomy remains the treatment of choice for patients with NMIBC who have failed intravesical therapy. However, evidence is accumulating that novel agents provide an efficacious alternative in patients refractory or intolerable to BCG or unfit for cystectomy. Further randomized prospective data are required to demonstrate a recurrence- and progression-free benefit compared with BCG.

Intravesical therapy for superficial bladder cancer: a systematic review of randomised trials and meta-analyses

BACKGROUND

In 2002 there were estimated to be 357,000 new cases of bladder cancer worldwide and 145,000 deaths making bladder cancer the 9th most common malignancy globally. At diagnosis, 60-80% of tumours are superficial and endoscopic resection is the initial treatment for this disease. In patients with low, medium or high risk disease, about 20%, 40% and 90%, respectively, will develop tumour recurrence. To delay or prevent recurrence, intravesical therapy is routinely used. Commonly used intravesical agents include immunotherapy with BCG and chemotherapy with cytotoxics such as Mitomycin C, Adriamycin, Epirubicin and Gemcitabine. However, controversy exists as to which agent and schedule should be used.

METHODS

An overarching search of the literature was used to identify relevant studies to assess the clinical benefit of intravesical therapy and provide clinical guidance in a comprehensive systematic review of randomised trials and meta-analyses of intravesical therapy for superficial bladder cancer. Findings and interpretation the search identified over 80 randomised trials and 11 meta-analyses. The extensive evidence suggests that an immediate post-operative instillation of a chemotherapeutic agent, such as Mitomycin C or Epirubicin, is effective in reducing tumour recurrence. In intermediate or high risk patients, further intravesical induction and maintenance therapy with BCG is recommended.

CONCLUSION

Intravesical chemotherapy with either Mitomycin C or Epirubicin would be an option for those patients failing or who are unsuitable for BCG therapy. Intravesical BCG is superior to chemotherapy in terms of complete response and disease-free survival. However, there is no conclusive evidence that one agent is superior in terms of overall survival.

Advances in the management of superficial bladder cancer

Given its high tendency to recur, coupled with an ever-present possibility to progress to potentially life-threatening muscle-invasive disease, superficial bladder cancer remains a challenging clinical problem. Optimal management begins with early detection and accurate risk assessment through careful attention to clinical features, aided by an emerging array of urinary markers and molecular characterizations. Prevention of recurrence requires the sequential application of tools to completely remove all visible disease, avert reimplantation during surgical resection, ablate microscopic foci, and prevent the emergence of new primary tumors amidst a field of carcinogen-exposed urothelium. Previously standard adjunctive intravesical chemo- and immunotherapies are enjoying new vitality as optimization strategies, new drugs, and rational drug combinations provide the potential for improved efficacy with reduced toxicity. New technological advances such as fluorescence-aided cystoscopy, microwave chemothermotherapy, and electromotive chemotherapeutic drug delivery offer further hope for better outcomes even for disease previously refractory to conservative measures. Yet despite these advances, aggressive surgical management involving bladder removal continues to be an indispensable life-saving maneuver that must be considered in all high-risk cases that fail to promptly respond to other measures.

Can intravesical bacillus Calmette-Guérin reduce recurrence in patients with superficial bladder cancer? A meta-analysis of randomized trials

OBJECTIVES

To determine whether intravesical bacillus Calmette-Guérin (BCG) administration reduces recurrence after transurethral resection of superficial bladder cancer using a meta-analysis.

METHODS

Published data of randomized clinical trials comparing transurethral resection plus intravesical BCG to either resection alone or resection plus another treatment were analyzed, considering possible confounding factors such as disease type, maintenance therapy, and others. Both the fixed effect model and the randomized effect model were applied, and the odds ratio (OR) with its 95% confidence interval (CI) was used as the effect size estimate.

RESULTS

We searched 176 trials, eliminated 151 of them, and identified 25 trials with recurrence information on 4767 patients. Of 2342 patients undergoing BCG therapy, 949 (40.5%) had tumor recurrence compared with 1205 (49.7%) of 2425 patients in the non-BCG group. In the combined results, a statistically significant difference in the OR for tumor recurrence between the BCG and no BCG-treated groups was found (randomized combined effect OR 0.61, 95% CI 0.46 to 0.80, P <0.0001). Stratified by BCG maintenance and disease type, the combined results of the individual reports showed statistical significance for BCG maintenance (OR 0.47, 95% CI 0.28 to 0.78, P = 0.004) and treatment of papillary carcinoma (OR 0.50, 95% CI 0.33 to 0.75, P = 0.0008). Chemotherapy and BCG plus chemotherapy/immunotherapy were not better than BCG alone.

CONCLUSIONS

Adjuvant intravesical BCG with maintenance treatment is effective for the prophylaxis of tumor recurrence in superficial bladder cancer. For patients with papillary carcinoma, adjuvant intravesical BCG with maintenance therapy should be offered as the treatment of choice.

High-grade Ta urothelial carcinoma and carcinoma in situ of the bladder

We sought to review the definition, diagnosis, prognosis, and treatment of high-grade Ta urothelioma carcinoma and carcinomas in situ (CIS) in order to provide evidence-based guidelines for their diagnosis and treatment. The English-language literature on high-grade Ta urothelial carcinoma and CIS was identified and critically reviewed by a panel of 9 international experts. The panel then met at a consensus conference to present their conclusions. Levels of evidence and grades of recommendation were assessed. Findings from approximately 100 publications appearing prior to February 2005 were reviewed and summarized. High-grade Ta urothelial carcinoma and CIS are relatively rare tumors; thus results are often based on small nonrandomized studies. Their assessment is made more difficult owing to inaccuracies in staging and grading. Although there were similar numbers of level 1, level 2, and level 3 evidence citations, guidelines have been developed based only on levels of evidence supporting grade A and grade B recommendations. These evidence-based guidelines have been developed to aid clinicians in the diagnosis and treatment of patients with high-grade Ta urothelial carcinoma and CIS.

EAU Guidelines on the Diagnosis and Treatment of Urothelial Carcinoma in Situ

OBJECTIVES

On behalf of the European Association of Urology (EAU), guidelines for the diagnosis, therapy and follow-up of patients with urothelial carcinoma in situ (CIS) have been established.

METHOD

The recommendations in these guidelines are based on a recent comprehensive overview and meta-analysis in which two panel members have been involved (RS and AVDM). A systematic literature search was conducted using Medline, the US Physicians' Data Query (PDQ), the Cochrane Central Register of Controlled Trials, and reference lists in trial publications and review articles.

RESULTS

Recommendations are provided for the diagnosis, conservative and radical surgical treatment, and follow-up of patients with CIS. Levels of evidence are influenced by the lack of large randomized trials in the treatment of CIS.

BACILLUS CALMETTE-GUERIN VERSUS CHEMOTHERAPY FOR THE INTRAVESICAL TREATMENT OF PATIENTS WITH CARCINOMA IN SITU OF THE BLADDER: A META-ANALYSIS OF THE PUBLISHED RESULTS OF RANDOMIZED CLINICAL TRIALS

PURPOSE

We determined the short-term and long-term efficacy of bacillus Calmette-Guerin (BCG) and chemotherapy in the treatment of patients with carcinoma in situ (CIS).

MATERIALS AND METHODS

A meta-analysis was performed on published results of randomized clinical trials comparing intravesical BCG to intravesical chemotherapy.

RESULTS

Nine randomized trials including 700 patients with CIS compared BCG to either mitomycin C (MMC), epirubicin, adriamycin, or sequential MMC/adriamycin. Of 298 patients on BCG 203 (68.1%) had a complete response compared with 158 of 307 patients on chemotherapy (51.5%), a reduction of 47% in the odds of nonresponse on BCG (OR 0.53, p =0.0002). Based on a median followup of 3.6 years, 161 of 345 patients on BCG (46.7%) had no evidence of disease compared with 93 of 355 patients on chemotherapy (26.2%), a reduction of 59% in the odds of treatment failure on BCG (OR 0.41, p <0.0001). Although the long-term benefit of BCG was smaller in trials with MMC, BCG was superior to MMC in trials with maintenance BCG (OR 0.57, p =0.04). The reduction of 26% in the risk of progression on BCG (p =0.20) is consistent with the reduction of 27% (p =0.001) previously reported in a larger superficial bladder cancer meta-analysis.

CONCLUSIONS

Intravesical BCG significantly reduces the risk of short and long-term treatment failure compared with intravesical chemotherapy. Therefore, it is considered to be the intravesical agent of choice in the treatment of CIS.

TUR and Adjuvant Intravesical Chemotherapy in T1G3 Bladder Tumors: Recurrence, Progression and Survival in 137 Selected Patients Followed Up to 20 Years

OBJECTIVES

To evaluate a highly selected population of patients affected by T1G3 bladder transitional cell carcinoma (TCCB) treated by transurethral resection (TUR) and adjuvant intravesical chemotherapy.

MATERIALS AND METHODS

Between January 1976 and April 1999, 137 patients with T1G3 TCCB were treated by TUR plus intravesical chemotherapy. Particularly, a sequential combination of mitomycin C (MMC) and epirubicin (EPI) was adopted in 91 patients (66.4%). The main exclusion criteria were concomitant or previous Tis, previous T1G3 TCCB, tumor size greater than 3 centimeters and number of tumors more than 3. TUR was repeated if a superficial tumor recurred. Patients went off study if Tis, recurrent T1G3 or invasive tumor were detected during treatment or thereafter. Adjuvant therapy, recurrence and progression were considered in multivariate analysis regarding recurrence, progression and survival respectively.

RESULTS

Observation period was up to 240 months with a minimum of 2 years in 112 patients (82%). Seventy patients (51%) recurred. The recurring tumor was again a T1G3 in 22 (16%) patients. Thirteen patients (9.5%) progressed. The 5-year progression-free survival rate was 90%. Median progression-free survival was 149 months. Twenty-two patients (16%) died, 9 (6.6%) of whom due to bladder cancer. Median overall survival was 155 months. The 3- and 5-year disease-free overall survival rates were 89% and 80% respectively. Ten cystectomies (7.3%) were performed. In conclusion, 123 patients (90%) maintained their intact bladder with a mean disease-free overall survival of 104 months. The sequential combination of MMC and EPI adjuvant therapy resulted more effective to be than single drug chemotherapy on recurrence rate (p=0.0021) but had no impact upon progression (p=0.127) and specific survival (p=0.163). Progression (p<0.001) after conservative treatment was the main prognostic factor for survival.

CONCLUSION

A conservative approach is an appropriate therapeutic option for the initial management of selected T1G3 bladder tumors.