Failure of bacille Calmette-Guérin in patients with high risk non-muscle-invasive bladder cancer unsuitable for radical cystectomy: an update of available treatment options

How to Perform Intravesical Chemotherapy after Second TURBT for Non-Muscle-Invasive Bladder Cancer: A Single-Center Experience

PURPOSE

The objective of this study aimed to explore whether the original IVC regimen should be continued after the second TURBT or whether the IVC induction phase should be restarted from the beginning.

METHODS

A retrospective analysis was performed on 137 patients who underwent a second TURBT at the Affiliated Hospital of Xuzhou Medical University between April 2014 and June 2022. Based on the pathological findings, patients were divided into two groups: group A patients, who did not have a residual tumor on pathological examination after the second TURBT; and group B patients, who had residual tumor. Recurrence was determined using cystoscopy and imaging every three months. The endpoint was recurrence-free survival.

RESULT

In the entire cohort, there was a statistically significant difference in the RFS between patients in the two IVC regimens (p = 0.029). The RFS of patients in group B1 was significantly lower than that of patients in group B2 (p = 0.009). There was no significant difference in RFS between the subgroups A1 and A2 (p = 0.560). Multivariate Cox regression analysis confirmed that the IVC regimen after a second TURBT (p = 0.012) and T stage after a second TURBT (p = 0.005) were both independent predictors for patient RFS.

CONCLUSION

If the pathological findings of the second TURBT specimen is benign, patients can continue their previous treatment regimen without restarting an IVC induction phase. Unnecessary IVC can be avoided in these patients. In contrast, for patients with residual tumors in the second TURBT specimen, the need to restart the IVC induction phase should be emphasized to improve patient prognosis.

Emerging treatments for bacillus Calmette-Guérin-unresponsive non-muscle-invasive bladder cancer

Intravesical bacillus Calmette–Guérin (BCG) immunotherapy has been the gold standard adjuvant treatment for intermediate- and high-risk non-muscle-invasive bladder cancer (NMIBC) after transurethral resection of bladder tumor (TURBT). BCG immunotherapy prevents disease recurrence and progression to muscle-invasive disease following TURBT. Although most patients initially respond well to intravesical BCG, considerable concern has been raised for patients with BCG failure who are refractory or recur in 6 months after their last BCG, which implies ‘BCG-unresponsiveness’. Based on current clinical guidelines, early radical cystectomy (RC) is recommended to treat BCG-unresponsive NMIBC. However, due to the high risk of morbidity and mortality of RC and patients' desire to preserve their own bladder, there is a critical unmet need for alternative conservative treatments as bladder-sparing strategies in BCG-unresponsive patients. Trials for effective bladder-sparing treatments are ongoing, and several novel agents have been recently tested in the NMIBC setting. The goal of this review is to introduce and summarize recently reported novel and emerging drugs and ongoing clinical trials for BCG-unresponsive NMIBC.

Selection of patients and benefit of immediate radical cystectomy for non-muscle invasive bladder cancer

Bladder cancer (BC) is a common disease in both sexes and majority of cases present as non-muscle invasive BC (NMIBC). The percentage of NMIBC progressing to muscle invasive BC (MIBC) varies between 25% and 75% and currently there are no reliable molecular markers that may predict the outcome of high-risk (HR) NMIBC. Transurethral resection of the bladder tumour (TURBT) with intravesical bacillus Calmette-Guérin (BCG) or immediate radical cystectomy (RC) are the current gold standard treatment options. The European Association of Urology (EAU) guidelines recommend immediate or delayed RC for HR- and a subgroup of "highest-risk" NMIBC. These cases include pT1, carcinoma in-situ (CIS), multifocal disease, histological variants such as micropapillary and sarcomatoid, and patients who have contraindications to, or have failed with BCG. The comparative risks between maintenance BCG (mBCG) and immediate RC are unclear. However, RC may give patients the best oncological outcome.

A pH-sensitive stearoyl-PEG-poly(methacryloyl sulfadimethoxine)-decorated liposome system for protein delivery: An application for bladder cancer treatment

Stealth pH-responsive liposomes for the delivery of therapeutic proteins to the bladder epithelium were prepared using methoxy-poly(ethylene glycol)5kDa-1,2-distearoyl-sn-glycero-3-phosphoethanolamine (mPEG5kDa-DSPE) and stearoyl-poly(ethylene glycol)-poly(methacryloyl sulfadimethoxine) copolymer (stearoyl-PEG-polySDM), which possesses an apparent pKa of 7.2. Liposomes of 0.2:0.6:100, 0.5:1.5:100 and 1:3:100 mPEG5kDa-DSPE/stearoyl-PEG-polySDM/(soybean phosphatidylcholine+cholesterol) molar ratios were loaded with bovine serum albumin (BSA) as a protein model. The loading capacity was 1.3% w/w BSA/lipid. At pH7.4, all liposome formulations displayed a negative zeta-potential and were stable for several days. By pH decrease or addition to mouse urine, the zeta potential strongly decreased, and the liposomes underwent a rapid size increase and aggregation. Photon correlation spectroscopy (PCS) and transmission electron microscopy (TEM) analyses showed that the extent of the aggregation depended on the stearoyl-PEG-polySDM/lipid molar ratio. Cytofluorimetric analysis and confocal microscopy showed that at pH6.5, the incubation of MB49 mouse bladder cancer cells and macrophages with fluorescein isothiocyanate-labelled-BSA (FITC-BSA) loaded and N-(Lissamine Rhodamine B sulfonyl)-1, 2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine triethylammonium salt (rhodamine-DHPE) labelled 1:3:100 mPEG5kDa-DSPE/stearoyl-PEG-polySDM/lipid molar ratio liposomes resulted in a time-dependent liposome association with the cells. At pH7.4, the association of BSA-loaded liposomes with the MB49 cells and macrophages was remarkably lower than at pH6.5. Confocal images of bladder sections revealed that 2h after the instillation, liposomes at pH7.4 and control non-responsive liposomes at pH7.4 or 6.5 did not associate nor delivered FITC-BSA to the bladder epithelium. On the contrary, the pH-responsive liposome formulation set at pH6.5 and soon administered to mice by bladder instillation showed that, 2h after administration, the pH-responsive liposomes efficiently delivered the loaded FITC-BSA to the bladder epithelium.

The effectiveness of BCG and interferon against non-muscle invasive bladder cancer: a New Zealand perspective

OBJECTIVE

To ascertain whether the current practice at Auckland City Hospital of adding interferon to BCG in patients with high risk or recurrent non-muscle invasive bladder cancer (NMIBC) unable or unwilling to undergo radical cystectomy is effective.

SUBJECTS AND METHOD

This study examined all institutional cases where BCG alone had not been effective or tolerated as primary treatment for NMIBC and the next guideline agreed step of radical cystectomy was unable to be performed. We identified all patients unwilling or unable to undergo radical cystectomy due to patient co-morbidities or preference for whom ongoing treatment and care was required and included 45 in the data analysis. Current practice at Auckland City Hospital is adding interferon α-2b to BCG for this population group and all patients that were given this therapy with at least three years of follow up data from diagnosis were included into the study. Patients were either on maintenance BCG or single dosing. Several secondary outcomes were also assessed concurrently to the primary objective.

RESULTS

This observational study showed that adding interferon to BCG proved to be an effective therapy for both treatment and salvage therapy in this patient group with 56% of the patients disease (and recurrence) free at the time of audit. 8/45 patients died whilst undergoing treatment with two of these as a direct result of bladder cancer due to disease progression.

CONCLUSION

This therapy has improved outcomes at our institution and has a place as a treatment of choice in this difficult to manage patient group.

Intravesical gemcitabine in combination with mitomycin C as salvage treatment in recurrent non-muscle-invasive bladder cancer

OBJECTIVES

To evaluate oncological outcomes after combination intravesical therapy with gemcitabine (GC) and mitomycin C (MMC) in the setting of recurrent non-muscle-invasive bladder cancer (NMIBC) after failure of previous intravesical therapy.

PATIENTS AND METHODS

We retrospectively identified patients with recurrent NMIBC after previous intravesical therapy, who refused or were not candidates for cystectomy, between 2005 and 2011. GC and MMC were sequentially instilled weekly for 6-8 weeks. Data were collected regarding patient demographics, bladder cancer history, and number and type of intravesical therapies before GC/MMC. Outcomes evaluated included time to recurrence and/or progression after GC/MMC. Recurrence-free outcomes were estimated using the Kaplan-Meier method, and Cox proportional hazards regression models were used to test the association of clinicopathological features with outcomes.

RESULTS

In all, 27 patients were identified, 23 with high-risk disease (high-grade or carcinoma in situ) and four with intermediate-risk disease (multifocal or recurrent low-grade). All patients received prior intravesical therapy, and 17 patients (63%) received multiple courses. Twenty-four patients were treated with BCG. The median (range) disease-free survival of all patients was 15.2 (1.7-39.3) months. Seventeen patients (63%) developed recurrent bladder cancer, a median of 15.2 months after therapy. One patient progressed to muscle-invasive disease 5 months after treatment, and one developed metastatic disease 22 months after treatment. Three patients went on to cystectomy. Ten patients (37%) had no evidence of disease at last follow-up, with a median follow-up of 22.1 months.

CONCLUSION

The combination of intravesical GC and MMC could offer durable recurrence-free survival to some patients with recurrent NMIBC who are not candidates for, or refuse, cystectomy.

Current perspectives in bladder cancer management

More than 350,000 new cases of bladder cancer are diagnosed worldwide each year; the vast majority (> 90%) of these are transitional cell carcinomas (TCC). The most important risk factors for the development of bladder cancer are smoking and occupational exposure to toxic chemicals. Painless visible haematuria is the most common presenting symptom of bladder cancer; significant haematuria requires referral to a specialist urology service. Cystoscopy and urine cytology are currently the recommended tools for diagnosis of bladder cancer. Excluding muscle invasion is an important diagnostic step, as outcomes for patients with muscle invasive TCC are less favourable. For non-muscle invasive bladder cancer, transurethral resection followed by intravesical chemotherapy (typically Mitomycin C or epirubicin) or immunotherapy [bacillus Calmette-Guérin (BCG)] is the current standard of care. For patients failing BCG therapy, cystectomy is recommended; for patients unsuitable for surgery, the choice of treatment options is currently limited. However, novel interventions, such as chemohyperthermia and electromotive drug administration, enhance the effects of conventional chemotherapeutic agents and are being evaluated in Phase III trials. Radical cystectomy (with pelvic lymphadenectomy and urinary diversion) or radical radiotherapy are the current established treatments for muscle invasive TCC. Neoadjuvant chemotherapy is recommended before definitive treatment of muscle invasive TCC; cisplatin-containing combination chemotherapy is the recommended regimen. Palliative chemotherapy is the first-choice treatment in metastatic TCC.

Intravesical therapies for bladder cancer - indications and limitations

• Intravesical therapy is a well-established treatment option for non-muscle-invasive bladder cancer (NMIBC). • Choosing the appropriate intravesical agent, schedule and duration of treatment has long been an area of debate. • We review the intravesical agents that are currently used in the management of NMIBC and examine the indications and limitations of their use. • Given the relative high rates of toxicity, failure and non-completion of traditional treatments we also examine some of the newer treatment options available.

Best practice in the treatment of nonmuscle invasive bladder cancer

Bladder carcinoma is the most common malignancy of the urinary tract. Approximately 75-85% of patients with bladder cancer present with a disease that is confined to the mucosa (stage Ta, carcinoma in situ) or submucosa (stage T1). These categories are grouped as nonmuscle invasive bladder cancer (NMIBC). Although the management of NMIBC tumours has significantly improved during the past few years, it remains difficult to predict the heterogeneous outcome of such tumours, especially if high-grade NMIBC is present. Transurethral resection is the initial treatment of choice for NMIBC. However, the high rates of recurrence and significant risk of progression in higher-grade tumours mandate additional therapy with intravesical agents. We discuss the role of various intravesical agents currently in use, including the immunomodulating agent bacillus Calmette-Guérin (BCG) and chemotherapeutic agents. We also discuss the current guidelines and the role of these therapeutic agents in the context of higher-grade Ta and T1 tumours. Beyond the epidemiology, this article focuses on the risk factors, classification and diagnosis, the prediction of recurrence and progression in NMIBC, and the treatments advocated for this invasive disease.

The role of a combined regimen with intravesical chemotherapy and hyperthermia in the management of non-muscle-invasive bladder cancer: a systematic review

CONTEXT

Due to the suboptimal clinical outcomes of current therapies for non-muscle-invasive bladder cancer (NMIBC), the search for better therapeutic options continues. One option is chemohyperthermia (C-HT): microwave-induced hyperthermia (HT) with intravesical chemotherapy, typically mitomycin C (MMC). During the last 15 yr, the combined regimen has been tested in different clinical settings.

OBJECTIVE

To perform a systematic review to evaluate the efficacy of C-HT as a treatment for NMIBC.

EVIDENCE ACQUISITION

The review process followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. An electronic search of the Medline, Embase, Cochrane Library, CancerLit, and ClinicalTrials.gov databases was undertaken. Relevant conference abstracts and urology journals were also searched manually. Two reviewers independently reviewed candidate studies for eligibility and abstracted data from studies that met inclusion criteria. The primary end point was time to recurrence. Secondary end points included time to progression, bladder preservation rate, and adverse event (AE) rate.

EVIDENCE SYNTHESIS

A total of 22 studies met inclusion criteria and underwent data extraction. When possible, data were combined using random effects meta-analytic techniques. Recurrence was seen 59% less after C-HT than after MMC alone. Due to short follow-up, no conclusions can be drawn about time to recurrence and progression. The overall bladder preservation rate after C-HT was 87.6%. This rate appeared higher than after MMC alone, but valid comparison studies were lacking. AEs were higher with C-HT than with MMC alone, but this difference was not statistically significant.

CONCLUSIONS

Published data suggest a 59% relative reduction in NMIBC recurrence when C-HT is compared with MMC alone. C-HT also appears to improve bladder preservation rate. However, due to a limited number of randomized trials and to heterogeneity in study design, definitive conclusions cannot be drawn. In the future, C-HT may become standard therapy for high-risk patients with recurrent tumors, for patients who are unsuitable for radical cystectomy, and in cases for which bacillus Calmette-Guérin treatment is contraindicated.