Efficacy of bacillus Calmette-Guérin Strains for Treatment of Nonmuscle Invasive Bladder Cancer: A Systematic Review and Network Meta-Analysis

European Association of Urology Guidelines on Non-muscle-invasive Bladder Cancer (TaT1 and Carcinoma In Situ)-A Summary of the 2024 Guidelines Update

BACKGROUND AND OBJECTIVE

This publication represents a summary of the updated 2024 European Association of Urology (EAU) guidelines for non-muscle-invasive bladder cancer (NMIBC), TaT1, and carcinoma in situ. The information presented herein is limited to urothelial carcinoma, unless specified otherwise. The aim is to provide practical recommendations on the clinical management of NMIBC with a focus on clinical presentation.

METHODS

For the 2024 guidelines on NMIBC, new and relevant evidence was identified, collated, and appraised via a structured assessment of the literature. Databases searched included Medline, EMBASE, and the Cochrane Libraries. Recommendations within the guidelines were developed by the panel to prioritise clinically important care decisions. The strength of each recommendation was determined according to a balance between desirable and undesirable consequences of alternative management strategies, the quality of the evidence (including the certainty of estimates), and the nature and variability of patient values and preferences.

KEY FINDINGS AND LIMITATIONS

Key recommendations emphasise the importance of thorough diagnosis, treatment, and follow-up for patients with NMIBC. The guidelines stress the importance of defining patients' risk stratification and treating them appropriately.

CONCLUSIONS AND CLINICAL IMPLICATIONS

This overview of the 2024 EAU guidelines offers valuable insights into risk factors, diagnosis, classification, prognostic factors, treatment, and follow-up of NMIBC. These guidelines are designed for effective integration into clinical practice.

A Territory-wide Study Investigating the Dose and Efficacy of Different Bacillus Calmette-Guérin Strains in Patients with Intermediate- and High-risk Non-muscle-invasive Bladder Cancer

BACKGROUND

Current European Association of Urology (EAU) guidelines support adjuvant intravesical Bacillus Calmette-Guérin (BCG) treatment after Transurethral Resection of Bladder Tumor (TURB) for intermediate- or high-risk Non-Muscle-Invasive Bladder Cancer (NMIBC) patients, aiming to reduce the risk of tumor recurrence. The quality of data, however, does not allow definitive conclusions on whether different strains and dosages of BCG have different efficacies on long-term survival outcomes.

OBJECTIVE

To evaluate the long-term survival outcomes of different strains and dosages of BCG in patients with NMIBC.

DESIGN, SETTING, AND PARTICIPANTS

All NMIBC patients treated with intravesical BCG therapy from 2001 to 2020 were identified using a territory-wide database in Hong Kong.

INTERVENTION

BCG strains and dosages (Connaught strain 81 mg, Connaught strain 27 mg, Tokyo strain 80 mg, and Danish strain 30 mg) were retrieved from medical records.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Overall Survival (OS), Cancer-Specific Survival (CSS), Recurrence-Free Survival (RFS), and Progression-Free Survival (PFS) were analyzed using the Kaplan-Meier method. A multivariable Cox regression analysis was used to adjust potential confounding factors, and to estimate Hazard Ratio (HR) and 95% confidence interval (CI) of different BCG strains. A further subgroup analysis on adequate versus inadequate BCG treatment was performed.

RESULTS AND LIMITATIONS

A total of 2602 NMIBC patients treated with intravesical BCG were identified. Among them, 1291 (49.6%) received Connaught strain 81 mg, 199 (7.6%) received Connaught strain 27 mg, 1014 (39.0%) received Tokyo strain, and 98 (3.8%) received Danish strain. The median follow-up was 11.0 years. No statistically significant differences in OS, CSS, RFS, and PFS were detected among the different groups. At the multivariable analysis, the Connaught strain 27 mg group was inferior to the Connaught strain 81 mg group in terms of OS (HR: 1.26, 95% CI: 1.05-1.51), CSS (HR: 1.69, 95% CI: 1.08-2.66), and PFS (HR: 1.86, 95% CI: 1.20-2.88). Adequate BCG treatment was associated with improved OS (HR: 0.82, 95% CI: 0.73-0.92), CSS (HR: 0.64, 95% CI: 0.47-0.86), RFS (HR: 0.80, 95% CI: 0.70-0.92), and PFS (HR: 0.52, 95% CI: 0.39-0.68). Among patients treated with adequate BCG, at the multivariable analysis the Connaught strain 27 mg group showed worse results than the Connaught strain 81 mg group in terms of CSS (HR: 1.93, 95% CI: 1.07-3.51). Compared with the Connaught strain 81 mg group, both Tokyo and Danish strains had similar survival outcomes in the whole cohort and the adequate BCG treatment subgroup.

CONCLUSIONS

Our findings suggest that adequate BCG remains the most important factor in optimizing survival outcomes in patients with intermediate- and high-risk NMIBC. No significant differences in survival outcomes were observed between full-dose Connaught, Tokyo, and Danish strains. Reduced-dose Connaught strain was associated with the worst survival outcomes.

PATIENT SUMMARY

We evaluated the efficacy of different strains and dosages of bacillus Calmette-Guérin (BCG) in patients with intermediate- or high-risk non-muscle-invasive bladder cancer in the past two decades in Hong Kong. We conclude no significant differences in long-term survival outcomes in terms of full-dose Connaught, Tokyo, and Danish strains, while reduced-dose Connaught strain was inferior to the full-dose group. Adequate BCG treatment benefits long-term survival.

Multi-omics analysis reveals that linoleic acid metabolism is associated with variations of trained immunity induced by distinct BCG strains

Trained immunity is one of the mechanisms by which BCG vaccination confers persistent nonspecific protection against diverse diseases. Genomic differences between the different BCG vaccine strains that are in global use could result in variable protection against tuberculosis and therapeutic effects on bladder cancer. In this study, we found that four representative BCG strains (BCG-Russia, BCG-Sweden, BCG-China, and BCG-Pasteur) covering all four genetic clusters differed in their ability to induce trained immunity and nonspecific protection. The trained immunity induced by BCG was associated with the Akt-mTOR-HIF1α axis, glycolysis, and NOD-like receptor signaling pathway. Multi-omics analysis (epigenomics, transcriptomics, and metabolomics) showed that linoleic acid metabolism was correlated with the trained immunity-inducing capacity of different BCG strains. Linoleic acid participated in the induction of trained immunity and could act as adjuvants to enhance BCG-induced trained immunity, revealing a trained immunity-inducing signaling pathway that could be used in the adjuvant development.

Comparative Analysis of Very Reduced vs Full Dose BCG Treatment for High-Risk Non-Muscle Invasive Bladder Cancer: A Contemporary Experience from Chile

BACKGROUND

Adjuvant bacillus Calmette-Guérin (BCG) is recommended for high-risk (HR) non-muscle invasive bladder cancer (NMIBC), but BCG shortages have led to exploration of reduced-dose regimens and shortened maintenance durations out of necessity, with limited data on treatment efficacy in Latin America.

OBJECTIVE

Oncological outcomes of HR-NMIBC patients treated with reduced (RD,1/4th dose) vs full dose (FD) BCG instillations of Danish Strain 1331 BCG.

METHODS

We performed a retrospective study of HR-NMIBC patients treated with BCG between 2003 and 2022 at our center in Santiago Chile. We stratified patients according to either RD (1/4th dose) or FD BCG. Univariate and multivariable Cox regression models were used to predict recurrence. Kaplan-Meier method was used to calculate survival estimates.

RESULTS

Of a total of 200 patients, 116 (58%) had RD and 84 (42%) FD BCG. Median follow-up was 57 months (IQR: 29-100). Patients who received FD BCG had a lower risk of recurrence (HR: 0.41, 95% CI 0.22-0.74) and high-grade (HG)-recurrence (HR: 0.30, 95% CI 0.15-0.61; p = 0.001). More patients in the RD vs FD group progressed to MIBC (10/84 vs 2/116; p = 0.18). Additionally, patients were less likely to stop BCG treatment in the RD group compared to the FD group due to toxicity (5% vs 11%, p = 0.14).

CONCLUSIONS

A 1/4th dose of Danish Strain 1331 BCG treatment was associated with worse recurrence free rate and HG-recurrence rate in our cohort. Patients with RD had lower discontinuation treatment rates due to a reduced toxicity profile. These findings would suggest that RD BCG would compromise oncological outcomes in HR-NMIBC patients.

Novel immunotherapeutic options for BCG-unresponsive high-risk non-muscle-invasive bladder cancer

BACKGROUND

High-risk non-muscle-invasive bladder cancer (HR-NMIBC) presents a challenge to many physicians due to its ability to resist Bacillus Calmette-Guérin (BCG) intravesical therapy and the substantial rate of progression into muscle-invasive bladder cancer (MIBC). Patients who are BCG-unresponsive have worse prognosis and thus require further management including radical cystectomy (RC), which significantly impacts quality of life. Moreover, the ongoing worldwide shortage of BCG warrants the need for policies that prioritize drug use and utilize alternative treatment strategies. Hence, there is a significant unmet need for bladder preserving therapy in this subset of patients.

METHODS

To address this issue, we searched the relevant literature in PUBMED for articles published from 2019 through May of 2023 using appropriate keywords. All clinical trials of patients with HR-NMIBC treated with immune-related agents were retrieved from clinicaltrials.gov.

FINDINGS AND FUTURE PERSPECTIVES

Exploratory treatments for BCG-Unresponsive HR-NMIBC included immune checkpoint inhibitors (ICI), oncolytic viral therapy, cytokine agonists, and other immunomodulators targeting TLR, EpCaM, FGFR, MetAP2, and IDO1. Some combination therapies have been found to work synergistically and are preferred therapeutically over monotherapy. Three drugs-pembrolizumab, valrubicin, and most recently, nadofaragene firadenovec-vncg-have been FDA approved for the treatment of BCG-unresponsive NMIBC in patients who are ineligible for or decline RC. However, all explored treatment options tend to postpone RC rather than provide long-term disease control. Additional combination strategies need to be studied to enhance the effects of immunotherapy. Despite the challenges faced in finding effective therapies, many potential treatments are currently under investigation. Addressing the landscape of biomarkers, mechanisms of progression, BCG resistance, and trial design challenges in HR-NMIBC is essential for the discovery of new targets and the development of effective treatments.

Seminal papers in urology: maintenance Bacillus Calmette-Guerin (BCG) immunotherapy for recurrent Ta, T1 and carcinoma in situ transitional cell carcinoma of the bladder: a randomized southwest oncology group study (SWOG-8507)

The South West Oncology Group's 2000 randomised-control trial investigated the addition of maintenance intravesical bacillus Calmette-Guerin (BCG) to non-muscle invasive urothelial carcinoma (NMIUC) treatment. The results were published when the efficacy of BCG immunotherapy maintenance was unclear.Randomisation produced two arms, each containing 192 patients assessed to be at high risk of recurrence following induction BCG therapy for NMIUC. The treatment arm went on to receive three successive weekly intravesical and percutaneous BCG administrations at three months, six months and then six monthly for three years from the start of induction therapy.Recurrence free-survival (RFS), was higher in the maintenance arm with 41% (95%CI 35-49) RFS at five years in the control arm and 60% RFS (53-67 95% CI) in the maintenance arm (p < 0.0001). Only 16% of patients in the treatment arm received all of the scheduled maintenance courses of BCG.The study's seminal results correlate with contemporary systematic review and have guided international guidelines.

The Impact of Dose Reduction of Bacillus Calmette-Guerin on Oncological Outcomes and Toxicity in Non-Muscle Invasive Bladder Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Bacillus Calmette-Guerin (BCG) is the standard adjuvant treatment for intermediate and high-risk non-muscle invasive bladder cancer (NMIBC) following transurethral resection of the bladder (TURB). However, the optimal dose, strain, and schedule of BCG remain unclear.

OBJECTIVE

To evaluate the impact of BCG dose reduction on oncological outcomes and toxicity in patients with non-muscle invasive bladder cancer.

METHODS

We performed a systematic review of the literature in PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov databases. Selected studies were analyzed for Meta Analysis using PRISMA criteria. The study focused on disease recurrence, progression, and toxicity. We also compared the oncological outcomes of the different BCG strains.

RESULTS

A total of 2963 patients in 13 randomized controlled trials were included. In recurrence analysis, we found a non-significant difference between the full dose and any dose reduction of BCG (RR = 1.17, [1.06-1.28], I2 = 0%, p = 0.7). In terms of progression, the difference was also non-statistically significant (RR: 1.12 [0.89 - 1.41], I2 = 0%, p = 0.93). In the toxicity analysis, there were more local (RR: 0.81 [0.67-0.99] I2 = 76%; p < 0.01) and systemic (RR: 0.53 [0.34-0.82] I2 = 83%; p < 0.01) side effects in the full dose group than in the dose reduction group. There were no statistically significant differences in oncological outcomes between the analyzed BCG strains.

CONCLUSIONS

Dose reduction did not affect the oncological outcomes of patients with NMIBC who received adjuvant therapy with BCG. On the other hand, dose reduction showed a significant trend towards fewer systemic and local side effects. Further studies comparing oncological and toxicity outcomes using different strains are needed.

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.

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.

Selective delipidation of Mycobacterium bovis BCG retains antitumor efficacy against non-muscle invasive bladder cancer

PURPOSE

Repeated instillations of bacillus Calmette et Guérin (BCG) are the gold standard immunotherapeutic treatment for reducing recurrence for patients with high-grade papillary non-muscle invasive bladder cancer (NMIBC) and for eradicating bladder carcinoma-in situ. Unfortunately, some patients are unable to tolerate BCG due to treatment-associated toxicity and bladder removal is sometimes performed for BCG-intolerance. Prior studies suggest that selectively delipidated BCG (dBCG) improves tolerability of intrapulmonary delivery reducing tissue damage and increasing efficacy in preventing Mycobacterium tuberculosis infection in mice. To address the lack of treatment options for NMIBC with BCG-intolerance, we examined if selective delipidation would compromise BCG's antitumor efficacy and at the same time increase tolerability to the treatment.

MATERIALS AND METHODS

Murine syngeneic MB49 bladder cancer models and in vitro human innate effector cell cytotoxicity assays were used to evaluate efficacy and immune impact of selective delipidation in Tokyo and TICE BCG strains.

RESULTS

Both dBCG-Tokyo and dBCG-TICE effectively treated subcutaneous MB49 tumors in mice and enhanced tumor-infiltrating CD8+ T and natural killer cells, similar to conventional BCG. However, when compared to conventional BCG, only dBCG-Tokyo retained a significant effect on intratumoral tumor-specific CD8+ and γδ T cells by increasing their frequencies in tumor tissue and their production of antitumoral function-related cytokines, i.e., IFN-γ and granzyme B. Further, dBCG-Tokyo but not dBCG-TICE enhanced the function and cytotoxicity of innate effector cells against human bladder cancer T24 in vitro.

CONCLUSIONS

These data support clinical investigation of dBCG-Tokyo as a treatment for patients with BCG-intolerant NMIBC.

Genomic, Metabolic, and Immunological Characterization of GMP-Grade Mycobacterium phlei

Mycobacterium phlei (M. phlei) is an understudied microbe with medical values as an immunomodulating agent. Here, we establish an industrial strain of M. phlei, CUD, and characterize its genomic, metabolic, and immunological profiles. The established strain has been stably passed for more than a decade, indicated by next-generation sequencing of its 5.3 Mb genome. We show that the intramuscular inoculation of heat-inactivated CUD in immunocompetent mice is well tolerated, and can mount immunological responses. Immunophenotyping demonstrates induced innate and adaptive immune responses in peripheral blood, spleen, and inguinal lymph nodes of CUD-treated mice. Using GC-TOF-MS, we find that the metabolomic profiles of different batches are highly concordant. These results demonstrate a highly reproducible production of M. phlei under GMP conditions.

IMPORTANCE Heat-inactivated M. phlei demonstrates promising efficacy to treat BCG-unresponsive non-muscle-invasive bladder cancer patients in clinical trials. However, lack of GMP-grade heat-inactivated M. phlei hampers further clinical investigations. Here, we described a GMP-grade, heat-inactivated M. phlei product, and presented initial characterization of its safety and immunomodulating properties. This product will serve as a starting point for further preclinical studies as well as clinical trials such as in combination with immune checkpoint inhibitors to treat bladder cancer.

Reactive Arthritis After Intravesical Bacillus Calmette-Guérin Therapy

ABSTRACT

Reactive arthritis (ReA) is a sterile arthritis that occurs in genetically predisposed individuals secondary to an extra-articular infection, usually of the gastrointestinal or genitourinary tract. Sterile arthritis associated with instillation of intravesical bacillus Calmette-Guérin (iBCG) therapy used for bladder cancer can also be included under ReA based on the pathogenic mechanism. Similar to spondyloarthritis, HLA-B27 positivity is a known contributor to the genetic susceptibility underlying iBCG-associated ReA. Other genetic factors, such as HLA-B39 and HLA-B51, especially in Japanese patients, can also be involved in the pathophysiology of iBCG-associated ReA. The frequencies of ReA- and ReA-related symptoms are slightly different between Japanese and Western studies. Proper understanding of possible complications, their epidemiology and pathogenesis, and their management is important for the rheumatologist when noting symptomatic patients using iBCG. Herein, we will review the most current information on ReA after iBCG therapy.

Evolution of immunotherapy in the treatment of non-muscle-invasive bladder cancer

INTRODUCTION

Immunotherapy with intravesical bacillus Calmette-Guérin (BCG) has been the gold standard treatment for intermediate- and high-risk non-muscle-invasive bladder cancer (NMIBC) for nearly half a century. Yet, many patients with high-risk disease will experience recurrence, including those who progress and eventually become unresponsive to BCG. For decades, apart from radical cystectomy, few therapeutic options existed for this at-risk population. However, the advent of novel immunotherapeutic agents has transformed treatment in a range of tumour types, including urothelial carcinoma. These immunotherapies have yielded promising results in the treatment of metastatic urothelial carcinoma and, as such, are also being investigated for use in NIMIBC.

AREAS COVERED

This article provides an overview of the evolution of immunotherapy for NMIBC, beginning from the original immunotherapy- BCG - to current agents including checkpoint inhibitors, IL-15 agonists, viral gene therapies and therapeutic cancer vaccines.

EXPERT OPINION

The KEYNOTE-057 trial represented a pivotal moment for immunotherapy in NMIBC, but patient selection and the development of biomarkers to guide the identification of patients who will benefit most from a particular immunotherapy remains critical. As research efforts come to fruition, novel immunotherapies may become integrated into the standard treatment paradigm for intermediate- and high-risk NMBIC.

Compared Efficacy of Adjuvant Intravesical BCG-TICE vs. BCG-RIVM for High-Risk Non-Muscle Invasive Bladder Cancer (NMIBC): A Propensity Score Matched Analysis

BACKGROUND

Intravesical immunotherapy with bacillus Calmette-Guerin (BCG) is the standard therapy for high-risk non-muscle invasive bladder cancer (NMIBC). The superiority of any BCG strain over another could not be demonstrated yet.

METHODS

Patients with NMIBCs underwent adjuvant induction ± maintenance schedule of intravesical immunotherapy with either BCG TICE or RIVM at two high-volume tertiary institutions. Only BCG-naïve patients and those treated with the same strain over the course of follow-up were included. One-to-one (1:1) propensity score matching (PSM) between the two cohorts was utilized to adjust for baseline demographic and tumor characteristics imbalances. Kaplan-Meier estimates and multivariable Cox regression models according to high-risk NMIBC prognostic factors were implemented to address survival differences between the strains. Sub-group analysis modeling of the influence of routine secondary resection (re-TUR) in the setting of the sole maintenance adjuvant schedule for the two strains was further performed.

RESULTS

852 Ta-T1 NMIBCs (n = 719, 84.4% on TICE; n = 133, 15.6% on RIVM) with a median of 53 (24-77) months of follow-up were reviewed. After PSM, no differences at 5-years RFS, PFS, and CSS at both Kaplan-Meier and Cox regression analyses were detected for the whole cohort. In the sub-group setting of full adherence to European/American Urology Guidelines (EAU/NCCN), BCG TICE demonstrated longer 5-years RFS compared to RIVM (68% vs. 43%, p = 0.008; HR: 0.45 95% CI 0.25-0.81).

CONCLUSION

When routinely performing re-TUR followed by a maintenance BCG schedule, TICE was superior to RIVM for RFS outcomes. However, no significant differences were detected for PFS and CSS, respectively.

Investigation of the causes of BCG refractory in patients treated with intracavitary BCG as secondary treatment in superficial bladder tumors with transurethral resection

BACKGROUND

Non-muscle invasive bladder cancers (NMIBC) tend to recur and progress over time. Bacillus Calmette-Guerin (BCG) is an effective therapy for the treatment of NMIBC in that it reduces both recurrence and progression rates. The present study investigates the causes of BCG failure, with emphasis on those attributable to application errors by the practitioner and/or patient.

METHODS

The demographic and histopathological characteristics of 115 patients who underwent TUR-B for primary bladder tumors and who underwent intracavitary BCG in the postoperative period in the Urology Clinic of the İzmir Katip Çelebi University Atatürk Training and Research Hospital between January 2014 and January 2019, were analyzed retrospectively. BCG-refractory patients were compared with non-BCG refractory patients after BCG administration.

RESULTS

The extent of the tumor, and the involvement of the tumor in the bladder trigone and/or the bladder neck were found to increase significantly the likelihood of BCG refractory. When the micturition times of both groups were compared after instillation, the differences between the groups were found to be statistically significant. In the BCG-refractory patient group, the micturition time after instillation was shorter due to the tumor involvement in the trigone/bladder neck.

CONCLUSION

Some modifiable factors originating from the patient and the tumoral characteristics were found to have an effect on BCG failure. It was further determined that the time until micturition after BCG administration is an important parameter to be considered in the prevention of application deficiencies. We believe these factors should be subjected to careful consideration during patient selection and follow-up.

Low-dose versus standard-dose bacille Calmette–Guérin for non-muscle-invasive bladder cancer: Systematic review and meta-analysis of randomized controlled trials

Purpose

Intravesical BCG (bacille Calmette–Guérin) instillation in patients with non-muscle-invasive bladder cancer decreases the risk for tumor recurrence and progression. After one BCG product was discontinued, a chronic global BCG shortage occurred. We focused on identifying a reduced dose of BCG that could maintain efficacy and reduce adverse effects.

Materials and Methods

We conducted a comprehensive literature search of PubMed, Embase, the Cochrane Library, CINAHL, Web of Science, and Scopus to identify randomized controlled trials through April 2021. The odds ratios (ORs) and 95% confidence intervals (CIs) for the low and standard doses in nine studies were compared. A low dose was defined as a low volume of BCG compared with the standard BCG dose (Armand Frappier, 120 mg; Connaught, 81 mg; Danish 1331, 120 mg; modified Danish 1331, 120 mg; Tokyo 172, 80 mg).

Results

The low-dose group experienced aggravated recurrence (OR, 1.45; 95% CI, 1.09–1.94; p=0.01) but similar progression (OR, 1.11; 95% CI, 0.76–1.62; p=0.59), similar cancer-specific survival (OR, 1.02; 95% CI, 0.60–1.75; p=0.93), similar overall survival (OR, 1.09; 95% CI, 0.76–1.56; p=0.65), favorable adverse effects (OR, 0.41; 95% CI, 0.28–0.62; p<0.0001), and favorable withdrawal (OR, 0.42; 95% CI, 0.25–0.71; p=0.001).

Conclusions

Low-dose BCG had more unfavorable outcomes than did standard-dose BCG in terms of recurrence. Tumor progression, cancer-specific survival, and overall survival were similar between the doses. Low-dose BCG improved adverse effects and withdrawal. In the setting of BCG shortage, low-dose BCG may have strong potential as an alternative.

Pharmacologic Therapies for Non-Muscle Invasive Bladder Cancer: Current and Future Treatments

Bladder cancer is the sixth most common malignancy in the United States and 70% of cases are non-muscle invasive at the time of diagnosis. Effective treatment is crucial to prevent progression, which occurs in about 30% of patients. The American Urological Association (AUA) guidelines recommend treatment of non-muscle invasive bladder cancer (NMIBC) with intravesical Bacille Calmette-Guerin (BCG) and chemotherapy. However, ongoing shortages and high rates of BCG unresponsiveness creates a major need for novel therapies. In this narrative review, we discuss the evolving landscape of therapeutic options for NMIBC. Pembrolizumab, an anti-programmed cell death (PD)-1 antibody, was the first systemic therapy to be FDA-approved for BCG-unresponsive, high-risk disease. Promising new agents under investigation include various other checkpoint inhibitors and adenovirus-based therapies including CG0070 and nadofaragene firadenovec (rAd-IFNa/Syn3). Finally, new mechanisms of drug delivery are under investigation, including delivery with the GemRIS (TAR-200) device and delivery of intravesical chemotherapy at higher temperatures. With the promise of novel therapies on the horizon, we can expect the role of urologists in the management of NMIBC to evolve and expand.

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

Objectives

We examined the outcomes of eight weekly bacillus Calmette–Guérin induction therapy after second transurethral resection, and investigated risk factors for intravesical recurrence or disease progression in high‐risk non‐muscle‐invasive bladder cancer patients.

Methods

This retrospective study included 146 high‐risk non‐muscle‐invasive bladder cancer patients who received eight weekly bacillus Calmette–Guérin instillations without a maintenance schedule between 2000 and 2019. Intravesical recurrence‐free and progression‐free survival rates were evaluated using the Kaplan–Meier method. The Cox proportional hazards model was used to identify risk factors.

Results

Pathological T staging in the first transurethral resection was pTa in 56 patients (38.4%), pT1 in 75 (51.4%) and primary carcinoma in situ in 15 (10.2%). A total of 109 (83.2%) with pTa–1 disease underwent second transurethral resection before bacillus Calmette–Guérin induction therapy, and residual disease was detected in 54 (49.5%). The completion rate of eight instillations was 82.2%. The 2‐ and 5‐year intravesical recurrence‐free survival rates were 80.7% and 75.2%, whereas the 2‐ and 5‐year progression‐free survival rates were 85.7% and 82.0%. Recurrent tumors (hazard ratio 6.5830, P = 0.0007) and residual tumors at the second transurethral resection (hazard ratio 4.0337, P = 0.0021) were risk factors for intravesical recurrence. Multiple tumors (hazard ratio 5.8056, P = 0.0302), pT1 disease (hazard ratio 3.7351, P = 0.0447) and residual tumors at second transurethral resection (hazard ratio 3.2552, P = 0.0448) were associated with disease progression.

Conclusions

Accurate disease staging and disease elimination by second transurethral resection followed by eight weekly bacillus Calmette–Guérin instillations achieved good disease control. Our protocol (without a maintenance schedule) after thorough surgical resection has potential as a treatment option in the current bacillus Calmette–Guérin shortage.

Immunotherapy for non-muscle-invasive bladder cancer: from the origins of BCG to novel therapies

Supplies of intravesical Bacillus Calmette-Guérin (BCG), the first-line treatment for most intermediate- and high-risk non-muscle-invasive bladder cancers (NMIBC), have proven unreliable over the past decade. This review considers the evolution of BCG immunotherapy for NMIBC: from the discovery of the antitumour side effects of tuberculosis and subsequently the BCG vaccine, to recent advances in novel immunotherapeutic agents. We summarize the evidence for alternative options to standard intravesical BCG therapy regimens and describe the potential for immune response manipulating drugs in the treatment of NMIBC. These new agents, including immune checkpoint inhibitors, toll-like receptor agonists and recombinant viral vectors, may provide better options in the management of NMIBC in the future.

Critical shortage in BCG immunotherapy: How did we get here and where will it take us?

Intravesical Bacillus Calmette-Guérin vaccine, one of the most successful bio-therapies to date, has been the gold standard treatment for non-muscle invasive bladder cancer for 44 years. International shortages have necessitated rationing this life-saving medication with deleterious effects on the primary treatment of high-grade non-muscle invasive bladder cancer. Understanding the history of intravesical Bacillus Calmette-Guérin gives us insight into the current shortages and future perspectives for novel immunotherapy opportunities against this deadly disease.

COVID-19 and Beyond: Exploring Public Health Benefits from Non-Specific Effects of BCG Vaccination

Bacille Calmette–Guérin (BCG) vaccination, widely used throughout the world to protect against infant tuberculous meningitis and miliary tuberculosis (TB), can provide broad non-specific protection against infectious respiratory diseases in certain groups. Interest in BCG has seen a resurgence within the scientific community as the mechanisms for non-specific protection have begun to be elucidated. The impact of the COVID-19 pandemic on nearly every aspect of society has profoundly illustrated the pressure that respiratory infections can place on a national healthcare system, further renewing interest in BCG vaccination as a public health policy to reduce the burden of those illnesses. However, the United States does not recommend BCG vaccination due to its variable effectiveness against adult TB, the relatively low risk of Mycobacterium tuberculosis infection in most of the United States, and the vaccine’s interference with tuberculin skin test reactivity that complicates TB screening. In this review, we explore the broad immune training effects of BCG vaccination and literature on the effects of BCG vaccination on COVID-19 spread, disease severity, and mortality. We further discuss barriers to scheduled BCG vaccination in the United States and how those barriers could potentially be overcome.

Effects of Mycobacterium bovis Calmette et Guérin (BCG) in oncotherapy: Bladder cancer and beyond

The Mycobacterium bovis Bacillus Calmette et Guérin (BCG) vaccine was generated in 1921 with the efforts of a team of investigators, Albert Calmette and Camille Guérin, dedicated to the determination to develop a vaccine against active tuberculosis (TB) disease. Since then, BCG vaccination is used globally for protection against childhood and disseminated TB; however, its efficacy at protecting against pulmonary TB in adult and aging populations is highly variable. Due to the BCG generated immunity, this vaccine later proved to have an antitumor activity; though the standing mechanisms behind are still unclear. Recent studies indicate that both innate and adaptive cell responses may play an important role in BCG eradication and prevention of bladder cancer. Thus, cells such as natural killer (NK) cells, macrophages, dendritic cells, neutrophils but also MHC-restricted CD4 and CD8 T cells and γδ T cells may play an important role and can be one the main effectors in BCG therapy. Here, we discuss the role of BCG therapy in bladder cancer and other cancers, including current strategies and their impact on the generation and sustainability of protective antitumor immunity against bladder cancer.

100 years of Bacillus Calmette-Guérin immunotherapy: from cattle to COVID-19

Bacillus Calmette-Guérin (BCG) is the most widely used vaccine worldwide and has been used to prevent tuberculosis for a century. BCG also stimulates an anti-tumour immune response, which urologists have harnessed for the treatment of non-muscle-invasive bladder cancer. A growing body of evidence indicates that BCG offers protection against various non-mycobacterial and viral infections. The non-specific effects of BCG occur via the induction of trained immunity and form the basis for the hypothesis that BCG vaccination could be used to protect against the severity of coronavirus disease 2019 (COVID-19). This Perspective article highlights key milestones in the 100-year history of BCG and projects its potential role in the COVID-19 pandemic.

The promise and perils of immunotherapy

Advances in understanding the ways in which the immune system fails to control tumor growth or prevent autoimmunity have led to the development of powerful therapeutic strategies to treat these diseases. In contrast to conventional therapies that have a broadly suppressive effect, immunotherapies are more akin to targeted therapies because they are mechanistically driven and are typically developed with the goal of "drugging" a specific underlying pathway or phenotype. This means that their effects and toxicities are, at least in theory, more straightforward to anticipate. The development of functionalized antibodies, genetically engineered T cells, and immune checkpoint inhibitors continues to accelerate, illuminating new biology and bringing new treatment to patients. In the following sections, we provide an overview of immunotherapeutic concepts, highlight recent advances in the field of immunotherapies, and discuss controversies and future directions, particularly as these pertain to hematologic oncology or blood-related diseases. We conclude by illustrating how original research published in this journal fits into and contributes to the overall framework of advances in immunotherapy.

European Association of Urology Guidelines on Non-muscle-invasive Bladder Cancer (Ta, T1, and Carcinoma in Situ)

CONTEXT

The European Association of Urology (EAU) has released an updated version of the guidelines on non-muscle-invasive bladder cancer (NMIBC).

OBJECTIVE

To present the 2021 EAU guidelines on NMIBC.

EVIDENCE ACQUISITION

A broad and comprehensive scoping exercise covering all areas of the NMIBC guidelines since the 2020 version was performed. Databases covered by the search included Medline, EMBASE, and the Cochrane Libraries. Previous guidelines were updated, and the level of evidence and grade of recommendation were assigned.

EVIDENCE SYNTHESIS

Tumours staged as Ta, T1 and carcinoma in situ (CIS) are grouped under the heading of NMIBC. Diagnosis depends on cystoscopy and histological evaluation of tissue obtained via transurethral resection of the bladder (TURB) for papillary tumours or via multiple bladder biopsies for CIS. For papillary lesions, a complete TURB is essential for the patient's prognosis and correct diagnosis. In cases for which the initial resection is incomplete, there is no muscle in the specimen, or a T1 tumour is detected, a second TURB should be performed within 2-6 wk. The risk of progression may be estimated for individual patients using the 2021 EAU scoring model. On the basis of their individual risk of progression, patients are stratified as having low, intermediate, high, or very high risk, which is pivotal to recommending adjuvant treatment. For patients with tumours presumed to be at low risk and for small papillary recurrences detected more than 1 yr after a previous TURB, one immediate chemotherapy instillation is recommended. Patients with an intermediate-risk tumour should receive 1 yr of full-dose intravesical bacillus Calmette-Guérin (BCG) immunotherapy or instillations of chemotherapy for a maximum of 1 yr. For patients with high-risk tumours, full-dose intravesical BCG for 1-3 yr is indicated. For patients at very high risk of tumour progression, immediate radical cystectomy should be considered. Cystectomy is also recommended for BCG-unresponsive tumours. The extended version of the guidelines is available on the EAU website at https://uroweb.org/guideline/non-muscle-invasive-bladder-cancer/.

CONCLUSIONS

These abridged EAU guidelines present updated information on the diagnosis and treatment of NMIBC for incorporation into clinical practice.

PATIENT SUMMARY

The European Association of Urology has released updated guidelines on the classification, risk factors, diagnosis, prognostic factors, and treatment of non-muscle-invasive bladder cancer. The recommendations are based on the literature up to 2020, with emphasis on the highest level of evidence. Classification of patients as having low, intermediate, or and high risk is essential in deciding on suitable treatment. Surgical removal of the bladder should be considered for tumours that do not respond to bacillus Calmette-Guérin (BCG) treatment and tumours with the highest risk of progression.

Does Switching Bacillus Calmette-Guerin Strains During Maintenance Therapy Affect the Outcome in Non-Muscle Invasive Bladder Cancer?

OBJECTIVE

To compare the patients who have received 1 type of BCG strain during maintenance therapy with patients treated with multiple BCG strains.

MATERIAL AND METHODS

We reviewed 279 patients treated with BCG between January 2012 and May 2019, retrospectively. The primary endpoints of the study were recurrence-free survival (RFS) and progression-free survival (PFS) rates among patients receiving same BCG strain (Group-1) and multiple BCG strains (Group-2). Matching analysis was performed to balance the groups. The Kaplan-Meier method was used for estimating RFS and PFS. The difference between the 2 groups in terms of adverse effects was evaluated using the chi-square test.

RESULTS

A total of 225 (80.6 %) patients were treated with single BCG strain, and 54 (19.4 %) were treated with multiple BCG strains. Overall, recurrence and progression was observed in 86 (30.8%) and 38 (13.6%) patients, respectively. There was no significant difference between the 2 groups in terms of recurrence-free survival and progression-free survival on both without matching and with propensity score match analysis (log rank; P=.760 and P=.559, P=.533 and P=0509 for non-match and matched analysis respectively). Most of the patients in both groups experienced BCG therapy related side effects, but there was no statistically significant difference between groups (P=.235/.833).

CONCLUSIONS

Switching the BCG strain because of unavailability of the induction strain does not decrease the effectiveness of the treatment. When it is not possible to reach the starting BCG strain, treatment can be safely continued with any available strain.

Novel and emerging approaches in the management of non-muscle invasive urothelial carcinoma

Non-muscle invasive bladder cancer (NMIBC) has traditionally been managed with transurethral resection followed by intravesical chemotherapy and/or bacillus Calmette-Guerin (BCG) in a risk-adapted manner. These tumors commonly recur and can progress potentially to lethal muscle invasive disease. A major unmet need in the field of NMIBC is bladder preserving therapy for recurrent high-grade NMIBC after adequate intravesical BCG therapy. The current gold standard treatment for these BCG-unresponsive patients is radical cystectomy, which is associated with considerable morbidity and mortality, particularly in older and frailer patients. It is therefore critical to provide alternative treatment options with acceptable oncological outcomes. In this review we explore novel bladder-sparing treatment options including combination intravesical therapy, enhanced instillation methods, immunotherapy, gene therapy, targeted therapy, photodynamic therapy and BCG variants across the spectrum of NMIBC disease states, ranging from low grade BCG-naïve patients through to high-grade BCG-unresponsive NMIBC.

Non-muscle-invasive bladder cancer: An overview of potential new treatment options

AIM

This review article summarizes the current clinical practice guidelines around disease definitions and risk stratifications, and the treatment of non-muscle-invasive bladder cancer (NMIBC). Recently completed and ongoing clinical trials of novel and investigational therapies in Bacillus Calmette-Guérin (BCG)-naïve, BCG-recurrent, and BCG-unresponsive patient populations are also described, e.g., those involving immune checkpoint inhibitors, targeted therapies, other chemotherapy regimens, vaccines, and viral- or bacterial-based treatments. Finally, a brief overview of enhanced cystoscopy and drug delivery systems for the diagnosis and treatment of NMIBC is provided.

BACKGROUND

A global shortage of access to BCG is affecting the management of BCG-naïve and BCG-recurrent/unresponsive NMIBC; hence, there is an urgent need to assist patients and urologists to enhance the treatment of this disease.

METHODS

Searches of ClinicalTrials.gov, PubMed, and Google Scholar were conducted. Published guidance and conference proceedings from major congresses were reviewed.

CONCLUSION

Treatment strategies for NMIBC are generally consistent across guidelines. Several novel therapies have demonstrated promising antitumor activity in clinical trials, including in high-risk or BCG-unresponsive disease. The detection, diagnosis, surveillance, and treatment of NMIBC have also been improved through enhanced disease detection.

The Use of Urine Mycobacterium tuberculosis Complex Polymerase Chain Reaction as a Predictive Factor for Recurrence and Progression After Intravesical Bacillus Calmette-Guérin Therapy in Patients with Non-muscle‑invasive Bladder Cancer

BACKGROUND

Intravesical bacillus Calmette-Guérin (BCG) instillation is a standard treatment for non-muscle-invasive bladder cancer (NMIBC); however, not all patients benefit from BCG therapy. Currently, no surrogate marker exists to predict BCG efficacy, and thereby, identify patients who will benefit from this treatment.

OBJECTIVE

To evaluate the utility of urine Mycobacterium tuberculosis complex polymerase chain reaction (MTC-PCR) assay as a predictive marker for recurrence and progression following BCG therapy.

DESIGN SETTING AND PARTICIPANTS

A prospective analysis was carried out for of intermediate- or high-risk NMIBC patients who received BCG instillation for the first time. Urine samples, for MTC-PCR assay, were collected at baseline and annually for up to 10 yr after the last BCG instillation, including induction and maintenance therapy. The first postoperative sample for MTC-PCR was taken at 1 yr from the last instillation.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

A survival analysis was performed using the Kaplan-Meier method, and risk factors for recurrence and progression after BCG treatment were assessed using Cox regression analysis.

RESULTS AND LIMITATIONS

During follow-up (median: 57 mo), 468/521 samples (89.8%) were MTC-PCR positive, and 108/123 patients (87.8%) exhibited MTC-PCR positivity at least once. Five-year recurrence- and progression-free survival in patients who were not MTC-PCR positive was significantly lower than in patients who were MTC-PCR positive at least once (p <  0.001). Using multivariable Cox regression analysis, MTC-PCR positivity at least once was a significant prognostic factor for recurrence (hazard ratio [HR]: 36.782, p <  0.001) and progression (HR: 47.209, p <  0.001).

CONCLUSIONS

Patients who were not MTC-PCR positive, even once after BCG therapy, were extremely likely to exhibit recurrence and progression. Urine MTC-PCR may be an extremely useful, noninvasive surrogate marker to predict recurrence and progression following BCG therapy.

PATIENT SUMMARY

Urine Mycobacterium tuberculosis complex polymerase chain reaction may be a novel biomarker capable of identifying patients at risk of recurrence and progression after bacillus Calmette-Guérin (BCG) immunotherapy.

Time interval from transurethral resection of bladder tumour to bacille Calmette-Guérin induction does not impact therapeutic response

OBJECTIVES

To investigate bacille Calmette-Guérin (BCG) tolerability and response with respect to the timing of BCG administration after transurethral resection of bladder tumour (TURBT) in patients with non-muscle-invasive bladder cancer (NMIBC).

PATIENTS AND METHODS

A review of patients with NMIBC at our institution managed with at least 'adequate BCG' (defined by the United States Food and Drug Administration as at least five of six induction instillations, with two additional instillations comprising either maintenance or repeat induction) at our institution from 2000 to 2018 was performed. Time from TURBT to first instillation of induction BCG was stratified by quartile and analysed as a continuous variable. Kaplan-Meier and log-rank tests analysed differences in recurrence-free (RFS) and progression-free survival (PFS). Cox proportional hazards regression models identified associations between risk factors and survival outcomes.

RESULTS

A total of 518 patients received adequate BCG at a median (range) of 26 (6-188) days from TURBT. Overall, 45 patients (9%) developed BCG intolerance at a median (range) 12 (7-33) instillations. When time from TURBT to BCG was stratified into quartiles, there was no difference with respect BCG intolerance (P = 0.966), RFS (P = 0.632) or PFS (P = 0.789). On both uni- and multivariate regression analysis for RFS and PFS, time from TURBT to BCG was not a significant predictor when analysed by quartile or as a continuous variable (the hazard ratio for RFS was 1.00, 95% confidence interval [CI] 0.99-1.00, P = 0.449; and for PFS was 0.99, 95% CI 0.98-1.00, P = 0.074).

CONCLUSION

The rates of tolerability and response to adequate BCG are not predicated by the timing of induction BCG instillation after TURBT. Early administration in properly selected patients is safe and delays do not affect therapeutic response.

Association of patients' sex with treatment outcomes after intravesical bacillus Calmette-Guérin immunotherapy for T1G3/HG bladder cancer

Purpose

To investigate the association of patients’ sex with recurrence and disease progression in patients treated with intravesical bacillus Calmette–Guérin (BCG) for T1G3/HG urinary bladder cancer (UBC).

Materials and methods

We analyzed the data of 2635 patients treated with adjuvant intravesical BCG for T1 UBC between 1984 and 2019. We accounted for missing data using multiple imputations and adjusted for covariate imbalance between males and females using inverse probability weighting (IPW). Crude and IPW-adjusted Cox regression analyses were used to estimate the hazard ratios (HR) with their 95% confidence intervals (CI) for the association of patients’ sex with HG-recurrence and disease progression.

Results

A total of 2170 (82%) males and 465 (18%) females were available for analysis. Overall, 1090 (50%) males and 244 (52%) females experienced recurrence, and 391 (18%) males and 104 (22%) females experienced disease progression. On IPW-adjusted Cox regression analyses, female sex was associated with disease progression (HR 1.25, 95%CI 1.01–1.56, p = 0.04) but not with recurrence (HR 1.06, 95%CI 0.92–1.22, p = 0.41). A total of 1056 patients were treated with adequate BCG. In these patients, on IPW-adjusted Cox regression analyses, patients’ sex was not associated with recurrence (HR 0.99, 95%CI 0.80–1.24, p = 0.96), HG-recurrence (HR 1.00, 95%CI 0.78–1.29, p = 0.99) or disease progression (HR 1.12, 95%CI 0.78–1.60, p = 0.55).

Conclusion

Our analysis generates the hypothesis of a differential response to BCG between males and females if not adequately treated. Further studies should focus on sex-based differences in innate and adaptive immune system and their association with BCG response.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00345-021-03653-1.

Immunotherapy in Bacillus Calmette-Guerin (BCG) unresponsive nonmuscle invasive bladder cancer

PURPOSE OF REVIEW

A number of promising therapies for Bacillus Calmette-Guerin (BCG) unresponsive nonmuscle invasive bladder cancer (NMIBC) are in the pipeline. In this review, we discuss the history of immunotherapy for the treatment of NMIBC and future developments, focusing on novel intravesical treatments.

RECENT FINDINGS

The term BCG unresponsive NMIBC encompasses patients with both BCG refractory and BCG relapsing disease. This definition was adopted to standardize inclusion criteria for patients enrolling in clinical trials in this setting. A host of intravesical immuno-oncologic therapies that include gene therapies, oncolytic viruses, cell surface molecule delivered immunotoxins, and cytokine driven agonism of cellular immunity, are in various phases of the drug development pipeline. In addition, pembrolizumab, an immune-checkpoint inhibitor, has recently been approved as a treatment option for BCG unresponsive NMIBC.

SUMMARY

Patients with BCG unresponsive disease face many difficulties. Although radical cystectomy is the most effective treatment option for these patients, it is associated with significant morbidity, difficult recovery challenges, and refusal by many patients. Cancer immunotherapies may provide bladder sparing options for some patients who develop BCG unresponsive disease.

Assessment of the oncological outcomes of three different bacillus Calmette-Guérin strains in patients with high-grade T1 non-muscle-invasive bladder cancer

Objective

: To determine whether there are significant differences in oncological outcomes between three different bacillus Calmette–Guérin (BCG) strains used for adjuvant intravesical immunotherapy in patients with high-grade T1 (T1HG) non-muscle-invasive bladder cancer (NMIBC).

Patients and methods

: Data of 590 patients with a diagnosis of primary T1HG NMIBC were retrospectively reviewed. The study included 138 (23.4%) patients who were treated with the Moreau, 272 (46.1%) with the TICE, and 180 (30.5%) with the RIVM strains. All patients included in the analysis received at least five instillations of an induction course and at least two installations of a maintenance course. Due to existing differences in baseline patient characteristics, the association between oncological outcomes and strain groups was investigated by complementary analysis with the implementation of inverse probability weighting (IPW).

Results

: The 5-year recurrence-free survival (RFS) rate was 70.5%, 66.7% and 55.2% for the Moreau, TICE and RIVM groups, respectively (P = 0.016). The 5-year progression-free survival (PFS) rates were 84.4%, 85% and 77.8% in the Moreau, TICE and RIVM groups, respectively (P = 0.215). The IPW-adjusted Cox proportional hazard regression analysis did not show any differences in RFS between the Moreau and TICE groups (P = 0.69), whereas the RIVM strain was significantly associated with worse RFS compared to the Moreau (hazard ratio [HR] 1.69 for RIVM; P = 0.034) and TICE (HR 1.87 for RIVM; P = 0.002) strains. The IPW-adjusted analysis did not show any significant differences between study groups in terms of PFS.

Conclusions

: The results of the present study suggest that the Moreau and TICE strains might be superior to the RIVM strain in terms of RFS in patients with T1HG NMIBC.

Abbreviations: CIS: carcinoma in situ; IPW: inverse probability weighting; IQR: interquartile range; HR: hazard ratio; HG: high grade; LVI: lymphovascular invasion; MP: muscularis priopria; NMIBC: non-muscle-invasive bladder cancer; PFS: progression-free survival; RCT: randomised controlled trial; RFS: recurrence-free survival; T1HG, high-grade T1; (re-)TURB: (re-staging) transurethral resection of bladder; VH: variant histology

Management of NMIBC during BCG shortage and COVID ‐19

Shortages of Bacille Calmette‐Guérin (BCG) have implications for the management of patients with non‐muscle‐invasive bladder cancers. Further complications come as a result of COVID‐19 for which BCG also shows some promising prospects.

Impact of maintenance therapy using a half dose of the bacillus Calmette-Guérin Tokyo strain on recurrence of intermediate and high-risk nonmuscle invasive bladder cancer: a retrospective single-center study

Background

Data are scarce regarding intravesical maintenance therapy (MT) with the low-dose bacillus Calmette–Guérin (BCG) Tokyo strain. We investigated the efficacy and safety of MT with a half dose of the Tokyo strain for patients following transurethral resection of nonmuscle invasive bladder cancer (NMIBC).

Methods

This study retrospectively reviewed clinical data on 78 patients diagnosed with intermediate or high-risk NMIBC followed by either MT (n = 38) or IT alone (n = 40) between January 2012 and March 2018. Statistical analysis was performed to compare recurrence-free survival (RFS) and adverse effects between the two groups. BCG was instilled once weekly for 6 weeks as IT, then once weekly in 2-week for a total of 20 instillations over 3 years.

Results

Kaplan–Meier analyses showed that patients undergoing MT had significantly better RFS than did those undergoing IT alone (hazard ratio (HR):0.32, 95% confidence interval (CI):0.12–0.89, P = 0.02). The 3-year RFS was 65.0% in the IT group and 89.5% in the MT group. Multivariate analysis showed that MT was associated with a reduced risk of recurrence (HR: 0.32, 95% CI:0.11–0.93, P = 0.03). One MT patient (2.6%) exhibited progression.

Conclusions

The BCG Tokyo strain showed acceptable efficacy and safety in patients undergoing MT; thus, it is a potential treatment for preventing bladder cancer recurrence.

Clinical and molecular insights into BCG immunotherapy for melanoma

The incidence of cutaneous melanoma and the mortality rate of advanced melanoma patients continue to rise globally. Despite the recent success of immunotherapy including ipilimumab and pembrolizumab checkpoint inhibitors, a large proportion of patients are refractory to such treatment modalities. The application of mycobacteria such as Bacillus Calmette-Guérin (BCG) in the treatment of various malignancies, including cutaneous melanoma, has been clearly demonstrated after almost a century of observations and experimentation. Intralesional BCG (IL-BCG) immunotherapy is a highly efficient and cost-effective treatment option for inoperable stage III in-transit melanoma, as recommended in the National Comprehensive Cancer Network Guidelines. IL-BCG has shown great efficacy in the regression of directly injected metastatic melanoma lesions, as well as distal noninjected nodules in immunocompetent patients. Clinical and preclinical studies have shown that BCG serves as a strong immune modulator, inducing the recruitment of various immune cells that contribute to antitumour immunity. However, the specific mechanism of BCG-mediated tumour immunity remains poorly understood. Comparative genome analyses have revealed that different BCG strains exhibit distinct immunological activity and virulence, which might impact the therapeutic response and clinical outcome of patients. In this review, we discuss the immunostimulatory potential of different BCG substrains and highlight clinical studies utilizing BCG immunotherapy for the treatment of cutaneous melanoma. Furthermore, the review focuses on the cellular and molecular mechanisms of the BCG-induced immune responses of both the innate and adaptive arms of the immune system. Furthermore, the review discussed the administration of BCG as a monotherapy or in combination with other immunotherapeutic or chemotherapeutic agents.

Bacillus Calmette-Guerin (BCG): Its fight against pathogens and cancer

Bacillus Calmette-Guerin (BCG) is the only FDA approved first line therapy for patients with nonmuscle invasive bladder cancer. Since the turn of the 20th century BCG has been used as a vaccine for protection against Mycobacterium tuberculosis (Mtb) and has also been found to have protection against nontuberculosis related pathogens. Recently the role of "trained immunity" has been identified as a possible mechanism for BCG vaccine-mediated immunity to Mtb. Similarly, BCG has been used as an immunotherapy for bladder cancer for more than 40 years, and the underlying mechanisms for BCG-mediated anti-tumor activity is poorly characterized. Several studies have shown that multiple immune pathways contribute to the immune response, and efficacy of intravesicle BCG as a cancer therapy. It is vital that we integrate our understanding of BCG as a vaccine and as a cancer therapeutic to facilitate design of future studies in order to maximize the immunotherapeutic potential of BCG. In this review we will outline the role of BCG as a vaccine, the known immune pathways that are activated by intravesical BCG and outline a potential clinical study integrating BCG vaccination prior to intravesicle instillation of BCG.

Efficacy of intravesical therapies on the prevention of recurrence and progression of non-muscle-invasive bladder cancer: A systematic review and network meta-analysis

Intravesical instillation therapy is the mainstay of prophylaxis of tumor recurrence and progression in non‐muscle‐invasive bladder cancer. However, there is no study evaluating the superiority of monotherapy. The aim of this study is to compare the efficacy of preventing recurrence and progression of intravesical monotherapies via network meta‐analysis (NMA) of randomized controlled trials. Database searches were conducted on Embase, Ovid Medline, Web of Science, ScienceDirect, Cochrane Library, and ClinicalTrials.com from the time of establishment to February 6, 2020. The monotherapies included Bacille Calmette‐Guérin (BCG), mitomycin C (MMC), interferon (IFN), adriamycin, epirubicin, gemcitabine (GEM), and thiotepa (THP). A Bayesian consistency network model was generated under a random‐effects model. The superiority of therapy was identified based on the surface under the cumulative ranking curve (SUCRA). Fifty‐seven studies with 12462 patients are included. NMA shows that GEM (SUCRA = 0.92), BCG (SUCRA = 0.82), and IFN (SUCRA = 0.78) are the top three effective drugs to reduce recurrence. GEM (SUCRA = 0.87) is the most effective therapy to prevent progress, followed by BCG, MMC, THP, and IFN with similar efficacy. Subgroup analysis of pairwise meta‐analysis and NMA was performed on publication year, trial initiation year, study origin, center involvement, sample size, drug schedule, tumor characteristics, and trial quality to address confounding factors, which suggests the robustness of the results with stable effect sizes. Network meta‐regression also indicates consistent rank by analyzing year, sample size, and quality. Compared with BCG, GEM is also a promising therapy with favorable efficacy to reduce tumor recurrence and progression. IFN and MMC could be alternative therapies for BCG with slightly inferior efficacy in recurrence prevention and similar efficacy in progression prevention. However, the results of this study should be treated with caution since most of the included studies are of moderate to high risk of bias.

Trained immunity as a molecular mechanism for BCG immunotherapy in bladder cancer

Intravesical BCG instillation is the gold-standard adjuvant immunotherapy for patients with high-risk non-muscle-invasive bladder cancer. However, the precise mechanism of action by which BCG asserts its beneficial effects is still unclear. BCG has been shown to induce a non-specific enhancement of the biological function in cells of the innate immune system, creating a de facto heterologous immunological memory that has been termed trained immunity. Trained immunity or innate immune memory enables innate immune cells to mount a more robust response to secondary non-related stimuli after being initially primed (or trained) by a challenge such as BCG. BCG-induced trained immunity is characterized by the metabolic rewiring of monocyte intracellular metabolism and epigenetic modifications, which subsequently lead to functional reprogramming effects, such as an increased production of cytokines, on restimulation. Results from BCG vaccination studies in humans show that trained immunity might at least partly account for the heterologous beneficial effects of BCG vaccination. Additionally, immunity might have a role in the effect of BCG immunotherapy for bladder cancer. Based on these indications, we propose that trained immunity could be one of the important mechanisms mediating BCG immunotherapy and could provide a basis for further improvements towards a personalized approach to BCG therapy in non-muscle-invasive bladder cancer.

Vaccinology: time to change the paradigm?

The existing vaccine paradigm assumes that vaccines only protect against the target infection, that effective vaccines reduce mortality corresponding to the target infection's share of total mortality, and that the effects of vaccines are similar for males and females. However, epidemiological vaccine research has generated observations that contradict these assumptions and suggest that vaccines have important non-specific effects on overall health in populations. These include the observations that several live vaccines reduce the incidence of all-cause mortality in vaccinated compared with unvaccinated populations far more than can be explained by protection against the target infections, and that several non-live vaccines are associated with increased all-cause mortality in females. In this Personal View we describe current observations and contradictions and define six emerging principles that might explain them. First, that live vaccines enhance resistance towards unrelated infections. Second, non-live vaccines enhance the susceptibility of girls to unrelated infections. Third, the most recently administered vaccination has the strongest non-specific effects. Fourth, combinations of live and non-live vaccines given together have variable non-specific health effects. Fifth, vaccinating children with live vaccines in the presence of maternal immunity enhances beneficial non-specific effects and reduces mortality. Finally, vaccines might interact with other co-administered health interventions, for example vitamin A supplementation. The potential implications for child health are substantial. For example, if BCG vaccination was given to children at birth, if higher measles vaccination coverage could be obtained, if diphtheria, tetanus, and pertussis-containing vaccines were not given with or after measles vaccine, or if the BCG strain with the best non-specific effects could be used consistently, then child mortality could be considerably lower. Pursuing these emerging principles could improve our understanding and use of vaccines globally.

Impact of substratification on predicting oncological outcomes in patients with primary high-risk non-muscle-invasive bladder cancer who underwent transurethral resection of bladder tumor

OBJECTIVES

To validate the substratification of high-risk in the European Association of Urology (EAU) guidelines and to develop the simplified substratification to improve usefulness and predictive accuracy on oncological outcomes in patients with primary high-risk nonmuscle-invasive bladder cancer (NMIBC) who underwent transurethral resection of bladder tumor (TURBT).

MATERIALS AND METHODS

We retrospectively evaluated 428 patients with primary high-risk NMIBC who underwent TURBT from November 1993 to April 2019. First, the efficacy of the EAU highest-risk on intravesical recurrence-free survival (RFS) and muscle-invasive bladder cancer (MIBC)-free survival was evaluated with univariate analyses. Second, we developed our simplified substratification based on multivariate analysis for intravesical RFS (lower- and higher-risk). We compared predictive accuracy on oncological outcomes using the receiver operating characteristic curve between the EAU and the simplified substratifications.

RESULTS

Median age and median follow-up periods were 72 years and 51 months, respectively. The EAU highest-risk was not associated with shorter intravesical RFS and MIBC-free survival (P = 0.054 and P = 0.350, respectively). In multivariate analysis, tumor size, grade 3, and chronic kidney disease were significantly associated with shorter intravesical RFS, and we developed the simplified substratification including those 3 factors. Of 428 patients, 89 (21%) were substratified into the simplified higher-risk. The predictive accuracy of the simplified substratification on intravesical recurrence, MIBC and metastasis progression, and cancer-specific mortality was significantly superior to the EAU substratification.

CONCLUSION

Our simplified substratification might contribute to improving predictive accuracy on intravesical recurrence, MIBC and metastasis progression, and cancer-specific mortality in patients with primary high-risk NMIBC who underwent TURBT.

Mycolicibacterium brumae Is a Safe and Non-Toxic Immunomodulatory Agent for Cancer Treatment

Intravesical Mycobacterium bovis Bacillus Calmette-Guérin (BCG) immunotherapy remains the gold-standard treatment for non-muscle-invasive bladder cancer patients, even though half of the patients develop adverse events to this therapy. On exploring BCG-alternative therapies, Mycolicibacterium brumae, a nontuberculous mycobacterium, has shown outstanding anti-tumor and immunomodulatory capabilities. As no infections due to M. brumae in humans, animals, or plants have been described, the safety and/or toxicity of this mycobacterium have not been previously addressed. In the present study, an analysis was made of M. brumae- and BCG-intravenously-infected severe combined immunodeficient (SCID) mice, M. brumae-intravesically-treated BALB/c mice, and intrahemacoelic-infected-Galleria mellonella larvae. Organs from infected mice and the hemolymph from larvae were processed to count bacterial burden. Blood samples from mice were also taken, and a wide range of hematological and biochemical parameters were analyzed. Finally, histopathological alterations in mouse tissues were evaluated. Our results demonstrate the safety and non-toxic profile of M. brumae. Differences were observed in the biochemical, hematological and histopathological analysis between M. brumae and BCG-infected mice, as well as survival curves rates and colony forming units (CFU) counts in both animal models. M. brumae constitutes a safe therapeutic biological agent, overcoming the safety and toxicity disadvantages presented by BCG in both mice and G. mellonella animal models.

Prospective evaluation of a urinary biomarker panel to detect and predict recurrence of non-muscle-invasive bladder cancer

PURPOSE

To perform a feasibility phase study of a panel of putative protein biomarkers and determine whether it can identify and predict tumor recurrence in patients with non-muscle-invasive bladder cancer (NMIBC) on follow-up.

METHODS

We prospectively analyzed the urine of 152 patients previously treated for NMIBC. Quantitative expression of plasminogen activator inhibitor-1 (PAI-1), DJ-1, apolipoprotein A-I (apoA-1), matrix metallopeptidase-9 (MMP-9), and interleukin-8 (IL-8) was assessed by enzyme-linked immunosorbent assay and compared amongst patients with and without bladder cancer recurrence at urine collection and during 3 years of follow-up. Tumor recurrence was confirmed by pathologic analysis. We performed a prediction analysis, excluding patients with recurrence at the start of the study, and assessed the influence of previous use of intravesical BCG on the level of biomarkers.

RESULTS

Median follow-up time was 47 months (interquartile range 39-50 months). Sixteen patients (10.5%) were diagnosed with recurrence at the start of the study, and 21 (15.4%) were diagnosed during the study. Three biomarker proteins (apoA-1, MMP-9, and IL-8) appear to hold diagnostic potential [odds ratio (OR) = 12.9; 95% CI 3.5-47.4]; while, PAI-1 and IL-8 predict recurrence (OR = 4.1; 95% CI 1.4-11.4). Previous use of intravesical BCG did not affect biomarker levels.

CONCLUSION

In the feasibility phase, the panel of urine biomarkers analyzed detected and predicted recurrence of NMIBC and provided reliable results in patients who had previously used intravesical BCG. Validation studies are required to confirm the panel clinical utility.