Effect of local hyperthermia of the bladder on mitomycin C pharmacokinetics during intravesical chemotherapy for the treatment of superficial transitional cell carcinoma

Experimental and New Approaches for Bladder Preservation in Intermediate and High-Risk Non-Muscle-Invasive Bladder Cancer (NMIBC)

About 75% of bladder cancers are detected as non-muscle invasive. High-risk patients have high progression risk. Although the standard is transurethral resection of bladder tumor plus full dose intravesical BCG for one to 3 years, due to the high risk of progression, radical cystectomy may be considered in specific cases. Although radical cystectomy is still the best approach for high-grade NMIBC from an oncological perspective, its high morbidity and impact on quality of life motivate studies of new strategies that may reduce the need for cystectomy. We carried out a mini-review whose objectives were: 1 - to identify bladder-sparing alternatives that are being studied as possible treatment for patients with intermediate and high-risk NMIBC; 2 - understand the evidence that exists regarding success rate, follow-up, and side effects of different strategies. Several studies have sought alternatives for bladder preservation, including immunotherapy, intravesical chemotherapy, chemo-hyperthermia, antibody-drug conjugates, viral genetic therapy, and others with promising results. The selection of an optimal therapy for high-risk NMIBC that can reduce the need for cystectomy, with low toxicity and high efficacy, is of paramount importance and remains an issue, however, several known medications are being tested as bladder-preserving alternatives in this scenario and have shown promise in studies.

Combination of hyperthermia and intravesical chemotherapy for the treatment of pT1 stage bladder cancer: A retrospectively clinical study

PURPOSE

To evaluate the efficiency and safety of combined local bladder hyperthermia and intravesical chemotherapy (IVC) for the treatment of patients with pT1 stage bladder cancer.

METHOD

A total of 189 patients with pT1 who underwent transurethral resection of bladder cancer (TURBT) were retrospectively reviewed. After TURBT, the patients with low-grade urothelial carcinoma (UC) were treated with either an IVC with pirarubicin (THP) protocol or chemo-thermotherapy (CHT) with THP protocol, whereas patients with high-grade UC were treated with either an intravesical immunotherapy (IVI) with bacillus Calmette-Guerin (BCG) protocol or CHT protocol, patients' characteristics, tumor biological features, and follow-up data were analyzed and compared between CHT and IVC group in low-grade UC, CHT, and IVI group in high-grade UC, respectively.

RESULTS

The median follow-up time was 24 months. In patients with low-grade UC, the median recurrence free survival (RFS) interval and costs of treatment in CHT group were significantly higher than those in IVC group (p = .01, p < .001, respectively), CHT was associated with higher RFS compared with IVC by Kaplan-Meier analysis, and three patients in IVC group upgraded to high grade when tumor recurred, whereas no cases were found upgraded in CHT group, p = .38. In patients with high-grade UC, tumor recurrence rates at 12 (p = .004) and 24 months (p = .004) after TURBT, rate of complications (p = .04)-especially for hematuresis (p = .03) and irritation symptoms (p = .04)-the median costs of treatment (p < .001) in CHT group were significantly lower than those in IVI group, RFS interval, health-related quality of life) at 12 and 24 months after TURBT in CHT group was significantly higher than those in IVI group (p < .001, p = .002, and p < .001, respectively), and CHT was associated with higher RFS compared with IVI by Kaplan-Meier analysis. The rate of patients upstaged to pT2 in CHT group seemed lower than that in IVI group, but there was no significantly statistical difference (14.3% vs. 24%, p = .58).

CONCLUSION

CHT has a beneficial prophylactic effect in patients with pT1 bladder cancer, especially in patients with high-grade UC, which is much more effective and safer than BCG, meanwhile it costs less compared with BCG.

BCG and Alternative Therapies to BCG Therapy for Non-Muscle-Invasive Bladder Cancer

Bladder cancer is a heterogeneous disease. Treatment decisions are mostly decided based on disease stage (non-muscle invasive or muscle invasive). Patients with muscle-invasive disease will be offered a radical treatment combined with systemic therapy, while in those with non-muscle-invasive disease, an attempt to resect the tumor endoscopically will usually be followed by different intravesical instillations. The goal of intravesical therapy is to decrease the recurrence and/or progression of the tumor. In the current landscape of bladder cancer treatment, BCG is given intravesically to induce an inflammatory response and recruit immune cells to attack the malignant cells and induce immune memory. While the response to BCG treatment has changed the course of bladder cancer management and spared many "bladders", some patients may develop BCG-unresponsive disease, leaving radical surgery as the best choice of curative treatment. As a result, a lot of effort has been put into identifying novel therapies like systemic pembrolizumab and Nadofaragene-Firadenovac to continue sparing bladders if BCG is ineffective. Moreover, recent logistic issues with BCG production caused a worldwide BCG shortage, re-sparking interest in alternative BCG treatments including mitomycin C, sequential gemcitabine with docetaxel, and others. This review encompasses both the historic and current role of BCG in the treatment of non-muscle-invasive bladder cancer, revisiting BCG alternative therapies and reviewing the novel therapeutics that were approved for the BCG-unresponsive stage or are under active investigation.

Progress and challenges in intravesical drug delivery

INTRODUCTION

Intravesical drug delivery (IDD) has gained recognition as a viable approach for treating bladder-related diseases over the years. However, it comes with its set of challenges, including voiding difficulties and limitations in mucosal and epithelial penetration. These challenges lead to drug dilution and clearance, resulting in poor efficacy. Various strategies for drug delivery have been devised to overcome these issues, all aimed at optimizing drug delivery. Nevertheless, there has been minimal translation to clinical settings.

AREAS COVERED

This review provides a detailed description of IDD, including its history, advantages, and challenges. It also explores the physical barriers encountered in IDD, such as voiding, mucosal penetration, and epithelial penetration, and discusses current strategies for overcoming these challenges. Additionally, it offers a comprehensive roadmap for advancing IDD into clinical trials.

EXPERT OPINION

Physical bladder barriers and limitations of conventional treatments result in unsatisfactory efficacy against bladder diseases. Nevertheless, substantial recent efforts in this field have led to significant progress in overcoming these challenges and have raised important attributes for an optimal IDD system. However, there is still a lack of well-defined steps in the workflow to optimize the IDD system for clinical settings, and further research is required to establish more comprehensive in vitro and in vivo models to expedite clinical translation.

Is CIS a Contraindication to Hyperthermic Intravesical Chemotherapy (HIVEC) after BCG-Failure?

CIS of the bladder is associated with a high risk of progression. In the case of BCG failure, radical cystectomy should be performed. For patients who refuse or are ineligible, bladder-sparing alternatives are evaluated. This study aims to investigate the efficacy of Hyperthermic IntraVesical Chemotherapy (HIVEC) depending on the presence or absence of CIS. This retrospective, multicenter study was conducted between 2016 and 2021. Patients with non-muscle-invasive bladder cancer (NMIBC) with BCG failure received 6-8 adjuvant instillations of HIVEC. The co-primary endpoints were recurrence-free survival (RFS) and progression-free survival (PFS). A total of 116 consecutive patients met our inclusion criteria of whom 36 had concomitant CIS. The 2-year RFS rate was 19.9% and 43.7% in patients with and without CIS, respectively (p = 0.52). Fifteen patients (12.9%) experienced progression to muscle-invasive bladder cancer with no significant difference between patients with and without CIS (2-year PFS rate = 71.8% vs. 88.8%, p = 0.32). In multivariate analysis, CIS was not a significant prognostic factor in terms of recurrence or progression. In conclusion, CIS may not be considered a contraindication to HIVEC, as there is no significant association between CIS and the risk of progression or recurrence after treatment.

Development and investigation of a novel device with gemcitabine for hyperthermic intravesical chemotherapy

PURPOSE

To evaluate the safety and efficacy of a novel hyperthermic intravesical chemotherapy (HIVEC) device in combination with gemcitabine.

MATERIALS AND METHODS

A pilot clinical trial was performed on patients with high-risk non-muscle invasive bladder cancer (NMIBC), who received HIVEC via the novel device (BR-PRG). Treatment regimen included eight weekly instillations of intravesical GEM (3 g in 150 mL normal saline [NS]) at a temperature of 45 °C for 60 min. Assessment of adverse events (AEs) was the primary objective of the trial. Disease recurrence and the thermal stability of GEM were also analyzed.

RESULTS

A total of 116 HIVEC treatments were delivered. Fifteen and eighteen patients were included in the effectiveness and safety analysis, respectively. Median follow-up was 12 months; five patients experienced a disease recurrence. One-year cumulative incidence of recurrence was 23.8% in EORTC intermediate risk group and 37.5% in high-risk group. Ten patients experienced at least one AE, with the most common being acute urinary tract infection, followed by urinary tract pain, and hematuria. Two patients experienced acute cystitis (grade 3 AE) and instillations were postponed until full recovery. Other AEs were minor, and no systemic toxicity was observed. The contents of GEM in solution of 0.9% NS or NS mixed with artificial urine were stable at 25 °C, 37 °C, 43 °C, 45 °C, 47 °C and 50 °C for 2 h.

CONCLUSION

GEM can be an ideal drug for use in HIVEC due to its good thermal stability. BR-PRG, combined with GEM was safe and effective in administering HIVEC.

Improved drug delivery and competitive adsorption of paclitaxel and mitomycin C anticancer drugs on the Boron-nitride nanoparticles: A molecular dynamics insight

The competitive aggregated adsorption and molecular interactions between paclitaxel (PX) and mitomycin C (MMC) molecules on the surface of boron nitride nanosheet (BNNS) was investigated using molecular dynamics method. BNNS...

Adverse events of hyperthermic intravesical chemotherapy for non-muscle invasive bladder cancer patients

INTRODUCTION

Non-muscle invasive bladder cancer (NMIBC) is one of the most frequent neoplasms in Denmark. Treatment of high-risk NMIBC usually consists of transurethral resection of bladder (TUR-B) followed by intravesical Bacillus Calmette-Guérin (BCG) instillations. Unfortunately, some patients are BCG-unresponsive and will relapse over time. Radical cystectomy is the recommended salvage treatment following BCG-failure or BCG-intolerance. However, not all patients are candidates for surgery and thus, in need of other treatment. This study investigates the adverse events of Hyperthermic Intravesical Chemotherapy (HIVEC) treatment.

METHODS

Twenty-three high-risk NMIBC patients, who were BCG-unresponsive or had contraindications for BCG, received HIVEC with Mitomycin C. Prior to each instillation, patients were interviewed by a nurse, using a systematic questionnaire regarding the adverse events. Patients were followed with cytology and cystoscopy every fourth month. The primary outcome was adverse event related to the HIVEC treatment.

RESULTS

In general, the adverse events were mild to moderate and often self-limiting. The most common adverse events were urinary frequency (23.6%), incontinence (19.4%) and urinary tract pain (12.2%).

CONCLUSION

In the current study, we found that HIVEC was a well-tolerated treatment. HIVEC might be a feasible option for patients, who experienced BCG-failure or BCG-intolerance and could potentially postpone or avoid radical cystectomy.

Current treatments for BCG failure in non-muscle invasive bladder cancer (NMIBC)

The treatment of choice for high-risk non-muscle invasive bladder cancer (NMIBC) is bacillus Calmette-Guérin (BCG). However, when this fails, the indicated treatment is radical cystectomy. In recent years, trials are being developed with various drugs to avoid this surgery in patients with BCG failure. The aim of this article is to update the treatments under study for bladder preservation in this patient population. Non-systematic review, searching PubMed with the terms "Bladder cancer", "Non-muscle invasive bladder cancer", "NMIBC", "BCG", "BCG-refractory", "Mitomycin C", "MMC", "Hyperthermia", "Electromotive Drug Administration", "EMDA". We used the search engines clinicaltrials.gov and clinicaltrialsregister.eu to find clinical trials. The only intravesical drug approved by the Food and Drug Administration (FDA) for carcinoma in situ (CIS) after failure to BCG is Valrubicin. Recently, the FDA has approved intravenous Pembrolizumab, following the publication of preliminary data from the KEYNOTE-057 study. Atezolizumab has demonstrated similar preliminary efficacy results. Only microwave-induced chemohyperthermia and EMDA-MMC (Electromotive Drug Administration) are recognized as alternatives in European guidelines. Other options under investigation are taxanes and gemcitabine, alone or in combination, recombinant viruses and device-assisted intravesical chemohyperthermia. The results of new drugs are promising, with a large number of trials underway. Knowing the mechanisms of resistance to BCG is essential to explore new therapeutic options.

Strategies to Get Drugs across Bladder Penetrating Barriers for Improving Bladder Cancer Therapy

Bladder cancer is a significant public health concern and social burden due to its high recurrence risk. Intravesical drug instillation is the primary therapy for bladder cancer to prevent recurrence. However, the intravesical drug therapeutic effect is limited by bladder penetrating barriers. The inadequate intravesical treatment might cause the low drug concentration in lesions, resulting in a high recurrence/progression rate of bladder cancer. Many strategies to get drugs across bladder penetrating barriers have been developed to improve intravesical treatment, including physical and chemical methods. This review summarizes the classical and updated literature and presents insights into great therapeutic potential strategies to overcome bladder penetrating barriers for improving the intravesical treatment of bladder cancer.

Development of a high-precision bladder hyperthermic intracavitary chemotherapy device for bladder cancer and pharmacokinetic study

BACKGROUND

Bladder hyperthermic intracavitary chemotherapy (HIVEC) has good effectiveness for bladder cancer, but conventional HIVEC systems lack precision and convenient application. To test the safety of a new HIVEC device (BR-TRG-II-type) in pigs and to perform a preliminary clinical trial in patients with bladder cancer.

METHODS

This device was tested on six pigs to optimize the temperature and time parameters. Then, 165 patients (HIVEC after transurethral resection (TUR), n = 128; or HIVEC, n = 37) treated between December 2006 and December 2016 were recruited. Mitomycin C (MMC) was the chemotherapeutic agent. A serum pharmacokinetic study was performed. The primary endpoints were tumor recurrence, disease-free survival (DFS), and cumulative incidence rate (CIR) during follow-up. The adverse effects were graded.

RESULTS

The animal experiment showed that 45 °C for 1 h was optimal. HIVEC was successful, with the infusion tube temperature stably controlled at about 45 °C, and outlet tube temperature of about 43 °C in all patients, for three sessions. Serum MMC levels gradually increased during HIVEC and decreased thereafter. The mean DFS was 39 ± 3.21 months (ranging from 8 to 78 months), and the DFS rate was 89.1% during follow-up. No adverse events occurred.

CONCLUSION

The use of the BR-TRG-II-type HIVEC device is feasible for the treatment of bladder cancer. Future clinical trials in patients with different stages of bladder cancer will further confirm the clinical usefulness of this device.

TRIAL REGISTRATION

chictr.org.cn: ChiCTR1900022099 (registered on Mar. 252,019). Retrospectively registered.

Intravesical device-assisted therapies for non-muscle-invasive bladder cancer

Non-muscle-invasive bladder cancer (NMIBC), the most prevalent type of bladder cancer, accounts for ~75% of bladder cancer diagnoses. This disease has a 50% risk of recurrence and 20% risk of progression within 5 years, despite the use of intravesical adjuvant treatments (such as BCG or mitomycin C) that are recommended by clinical guidelines. Intravesical device-assisted therapies, such as radiofrequency-induced thermochemotherapeutic effect (RITE), conductive hyperthermic chemotherapy, and electromotive drug administration (EMDA), have shown promising efficacy. These device-assisted treatments are an attractive alternative to BCG, as issues with supply have been a problem in some countries. RITE might be an effective treatment option for some patients who have experienced BCG failure and are not candidates for radical cystectomy. Data from trials using EMDA suggest that it is effective in high-risk disease but requires further validation, and results of randomized trials are eagerly awaited for conductive hyperthermic chemotherapy. Considerable heterogeneity in patient cohorts, treatment sessions, use of maintenance regimens, and single-arm study design makes it difficult to draw solid conclusions, although randomized controlled trials have been reported for RITE and EMDA.

Device-assisted intravesical therapy for non-muscle invasive bladder cancer

Non-muscle invasive bladder cancer (NMIBC) is a challenging disease, with a high risk of recurrence and even progression to muscle invasive disease. The present standard treatment is suboptimal, and consists of a complete transurethral resection of the visible bladder tumour(s), followed by prophylactic intravesical instillations mitomycin-C (MMC) or bacillus Calmette-Guérin (BCG). In search for higher efficacy, several adjuvant device-assisted intravesical therapies are developed. Chemohyperthermia may be based on microwave-/radiofrequency-induced (RF) hyperthermia systems, for which most evidence exists, or on hyperthermic intravesical chemotherapy, which is applied by conductive or loco-regional heating systems. RF-induced CHT has shown superiority over MMC alone, and in one prospective study superiority over BCG in per-protocol analysis, which has led to the ‘weak’ recommendation in the EAU guidelines to consider RF-based CHT as a bladder preservation strategy in patients with BCG-refractory tumours, who are not candidates for radical cystectomy due to comorbidities. Prospective studies on hyperthermic intravesical chemotherapy for patients with intermediate-risk NMIBC are awaited next year. The combination of electromotive drug administration (EMDA) with MMC has shown superiority over MMC as well, and seems promising when combined with BCG in sequential treatment. Photodynamic therapy should still be considered experimental, in which a study with the intravenous photosensitizer Radachlorin^® has shown promising results.

Hyperthermic Intravesical Chemotherapy for BCG Unresponsive Non-Muscle Invasive Bladder Cancer Patients

Background:

Adjuvant intravesical instillations with bacillus Calmette-Guérin (BCG) is the recommended treatment option for patients with intermediate-and high-risk non-muscle invasive bladder cancer (NMIBC). Despite adequate BCG treatment, a large proportion of patients experience a recurrence. Although radical cystectomy is the gold standard for BCG unresponsive NMIBC, some patients are unfit or unwilling to consider this option.

Objective:

To assess the effectiveness of Hyperthermic IntraVEsical Chemotherapy (HIVEC^®) in BCG unresponsive NMIBC patients.

Methods:

A post-hoc analysis was conducted of prospectively included intermediate-and high-risk NMIBC patients who were planned to receive HIVEC^® treatment between October 2014 and November 2017. For the present analysis, only patients who met the BCG unresponsive definition were included. Patients were followed by cystoscopy and cytology every 3 months and a CT-urography scan yearly. The primary outcome was the disease-free survival (DFS). The Common Terminology Criteria for Adverse Events (CTCAE) was used to assess side-effects.

Results:

The study population consisted of 55 BCG unresponsive NMIBC patients of whom 52 underwent≥5 HIVEC^® treatments. The median age and follow-up were 73 years and 14.0 months (IQR 7.6 – 24.6). The median DFS was 17.7 months (SE 6.72) and progression occurred in four patients. The 1-year cumulative incidence rate of disease recurrence/progression was 53%. Two patients experienced severe side-effects (CTCAE≥3).

Conclusions:

HIVEC^® seems a valid treatment option for BCG unresponsive NMIBC patients. We report a median DFS of 17.7 months (SE 6.72), potentially avoiding or postponing the need for radical surgery in a proportion of these patients.

Solubilization and Stability of Mitomycin C Solutions Prepared for Intravesical Administration

BACKGROUND

Mitomycin C (MMC) is an antitumor agent that is often administered intravesically to treat bladder cancer. Pharmacologically optimized studies have suggested varying methods to optimize delivery, with drug concentration and solution volume being the main drivers. However, these MMC concentrations (e.g. 2.0 mg/mL) supersede its solubility threshold, raising major concerns of inferior drug delivery.

OBJECTIVE

In this study, we seek to confirm that the pharmacologically optimized MMC concentrations are achievable in clinical practice through careful modifications of the solution preparation methods.

METHODS

MMC admixtures (1.0 and 2.0 mg/mL) were prepared in normal saline using conventional and alternative compounding methods. Conventional methodology resulted in poorly soluble solutions, with many visible particulates and crystallates. However, special compounding methods, which included incubation of solutions at 50 °C for 50 min followed by storage at 37 °C, were sufficient to solubilize drug. Chemical degradation of MMC solutions was determined over 6 h using high-performance liquid chromatography (HPLC) analytics, while physical stability was tested in parallel.

RESULTS

Immediately following the 50 min incubation, both MMC solutions exhibited approximately 5-7% drug degradation. Based on the measured concentrations and linear regression of degradation plots, additional storage of these solutions at 37 °C for 5 h retained chemical stability criterion (< 10% overall drug loss). No physical changes were observed in any solutions at any test time points.

CONCLUSION

We recommend that the described alternative preparation methods may improve intravesicular delivery of MMC in this urological setting, and advise that clinicians employing these changes should closely monitor patients for MMC toxicities and pharmacodynamics (change in clinical outcomes) that result from the potential enhancement of MMC exposure in the bladder.

Intravesical radiofrequency induced hyperthermia enhances mitomycin C accumulation in tumour tissue

INTRODUCTION

Non-muscle invasive bladder cancer (NMIBC) is a highly recurrent disease with potential progression to muscle invasive disease despite the standard bladder instillations with mitomycin C (MMC) or Bacille Calmette-Guérin immunotherapy. Therefore, alternatives such as radiofrequency-induced chemohyperthermia (RF-CHT) with MMC are being investigated. The mechanism explaining the efficacy of RF-CHT is only partly understood. We examined whether RF-CHT results in higher MMC tissue concentrations as compared to cold MMC instillation.

PATIENTS AND METHODS

Prior to a planned transurethral resection of bladder tumour (TURBT), patients with stage Ta NMIBC were allocated to either (1) cold MMC instillation or (2) RF-CHT. After MMC instillation, three biopsies were taken of both normal and tumour tissue. Biopsies were snap-frozen and MMC tissue concentrations were analysed using ultra-performance liquid chromatography.

RESULTS

Eleven patients were included of which six received RF-CHT. Ten patients had TaG2-LG/HG papillary tumours at pathology. One patient in the RF-CHT group appeared to be free of malignancy and was excluded from the analysis as no tumour biopsies were available. The median MMC concentration in tumour tissue was higher in the RF-CHT group (median 665.00 ng/g vs. 63.75 ng/g, U = 51.0, p = 0.018). Moreover, in both techniques the MMC concentration was lower in normal tissue compared to tumour tissue. Tissue MMC concentration measurements varied substantially within, and between, different patients from the same group.

CONCLUSION

Intravesical RF-CHT results in higher tumour MMC concentrations vs. cold MMC instillation which contributes to its superior efficacy.

Lyso-thermosensitive liposomal doxorubicin for treatment of bladder cancer

PURPOSE

To evaluate lyso-thermosensitive liposomal doxorubicin (LTLD, ThermoDox®) in combination with loco-regional mild hyperthermia (HT) for targeted drug delivery to the bladder wall and potential treatment of bladder cancer.

MATERIAL AND METHODS

Porcine in vivo studies were performed with the following groups: (i) intravenous (IV) LTLD with hyperthermia (LTLD + HT); (ii) IV doxorubicin (DOX) with hyperthermia (IV DOX + HT) and (iii) IV LTLD without hyperthermia (LTLD - HT). Drug formulations were delivered via 30 min IV infusion coinciding with 1-h bladder irrigation (45 °C water for HT groups, 37 °C for non-HT group), followed by immediate bladder resection. DOX concentrations were measured in consecutive sections parallel to the bladder lumen by liquid chromatography following drug extraction. Computer models were developed to simulate tissue heating and drug release from LTLD.

RESULTS

Comparing mean DOX concentrations at increasing depths from the lumen to outer surface of the bladder wall, the ranges for LTLD + HT, IV DOX + HT and LTLD - HT, respectively, were 20.32-3.52 μg/g, 2.34-0.61 μg/g and 2.18-0.51 μg/g. The average DOX concentrations in the urothelium/lamina and muscularis, respectively, were 9.7 ± 0.67 and 4.09 ± 0.81 μg/g for IV LTLD + HT, 1.2 ± 0.39 and 0.86 ± 0.24 μg/g for IV DOX + HT, and 1.15 ± 0.38 and 0.62 ± 0.15 μg/g for LTLD - HT. Computational model results were similar to measured DOX levels and suggest adequate temperatures were reached within the bladder wall for drug release from LTLD.

CONCLUSIONS

Doxorubicin accumulation and distribution within the bladder wall was achieved at concentrations higher than with free IV doxorubicin by mild bladder hyperthermia combined with systemic delivery of LTLD.

Recirculating chemohyperthermia as a treatment for non-muscle invasive bladder cancer: Current and future perspectives

About 75% of all bladder cancer diagnosed are non-muscle invasive bladder cancer (NMIBC), recurring over 50% of them after transurethral resection of the bladder tumor. In order to prevent recurrences, adjuvant intravesical chemotherapy with mitomycin C and immunotherapy with bacillus Calmette-Guérin (BCG) is traditionally used. Unfortunately, many patients relapse after receiving these treatments and a significant proportion of them require surgery. After a one-to-three years BCG maintenance, the risk for progression at 5 years was 19.3% for T1G3 tumors. Many new treatment approaches are being investigated to increase the effectiveness of adjuvant intravesical therapy. One of the developing treatments for intermediate and high-risk NMIBC is the combination of intravesical chemotherapy and hyperthermia, called chemohyperthermia. This article provides a review of the mechanism of action, current status and indications, results and future perspectives.

Bladder intracavitary hyperthermic perfusion chemotherapy for the prevention of recurrence of non-muscle invasive bladder cancer after transurethral resection

Preventing the recurrence of non-muscle invasive bladder cancer (NMIBC) post-transurethral resection (TUR) remains challenging. The aim of the present study was to investigate the effectiveness and safety of bladder intracavitary hyperthermic perfusion chemotherapy (BHPC) for prevention of NMIBC recurrence post-TUR. Between December 2006 and December 2014, 53 patients with NMIBC who underwent TUR were randomly assigned to receive BHPC (BHPC group, 28 patients) or intravesical chemotherapy alone (chemotherapy group, 25 patients) at the Intracelom Hyperthermic Perfusion Therapy Center of Guangzhou Medical University Cancer Hospital (Guangzhou, China). BHPC was performed by combining perfusion-based hyperthermia with chemotherapeutic agent mitomycin C (MMC) in the bladder, and the chemotherapy group of patients received bladder MMC perfusion. The concentration of MMC in the perfusion fluid and serum were assessed at different time-points. Tumor recurrence, disease-free survival (DFS), and side-effects were recorded and compared between the 2 groups. Results revealed that BHPC was performed smoothly, at ~44̊C in the bladder cavity. Patients tolerated BHPC, and no side-effects were observed. Both BHPC and intravesical chemotherapy achieved a high MMC concentration in the bladder perfusion liquid, but low MMC concentration in the serum, although serum MMC concentrations in the BHPC group were significantly higher (P<0.05). The tumor recurrence rate was significantly lower (10.7 vs. 28.0%; P=0.02) and the DFS period was significantly longer (37±1.2 vs. 19±0.9 months; P=0.001) in the BHPC group than in the chemotherapy group. Our results demonstrated that BHPC is safe and effective for preventing NMIBC recurrence post-TUR and prolongs DFS.

Intravesical radiofrequency-induced hyperthermia combined with chemotherapy for non-muscle-invasive bladder cancer

Although many treatment modalities and schedules for non-muscle-invasive bladder cancer (NMIBC) exist, all yet prove to have limitations. Therefore the search for new forms of therapy continues. One of these forms consists of combining intravesical chemotherapy, typically mitomycin C (MMC), with hyperthermia achieved by a microwave-applicator. We aimed to review the current status of intravesical radiofrequency (RF) induced chemohyperthermia (CHT) for NMIBC with regard to efficacy, adverse-events (AEs) and its future perspective. A search for RF-induced CHT in MEDLINE, Embase, Cochrane and ClinicalTrials.gov databases was performed. Relevant conference abstracts were searched for manually. If applicable, experts on the area were consulted. Papers were selected based on abstract and title. A table of newly published clinical trials since 2011 was constructed. No meta-analysis could be performed based on these new papers. Efficacy proved to be better for RF-induced CHT compared to both MMC alone and bacillus Calmette-Guérin (BCG) instillations, with the latter being based on just one abstract of a randomised controlled trial. The AE rate in CHT is higher compared to MMC instillation, but is similar compared to BCG, albeit different in the type of AE. In almost all studies no severe AEs are reported. Although heterogeneity in methodology exists, RF-induced CHT seems promising. However, alternative methods of applying hyperthermia are starting to present their first results, imposing as effective options too. Intravesical RF-induced CHT may become an alternative for BCG instillation, and possibly for cystectomy, although further level 1 evidence is required for both reliable and reproducible data on efficacy and adverse events.

Radiofrequency-Induced Thermo-Chemotherapy Effect (Rite) for Non Muscle Invasive Bladder Cancer Treatment: Current Role and Perspectives

Although many treatment modalities and schedules for nonmuscle invasive bladder cancer (NMIBC) exist, all yet prove to have limitations and the search for new therapeutic strategies continues. Among these, the combination of intravesical chemotherapy and microwave-induced local hyperthermia has been investigated and clinically tested during more than 15 years.

Objective

An updated review of intravesical radiofrequency (RF)-induced thermo-chemotherapy effect (RITE) for NMIBC with regard to efficacy, adverse events (AEs) and perspectives.

Evidence Acquisition

An extensive and sensitive search for RF-induced chemo-hyperthermia in Medline, Embase, Cochrane and ClinicalTrials.gov databases was performed. A table of published clinical trials up to 2016 was constructed. No meta-analysis could be performed on the basis of new papers.

Evidence Synthesis

Recurrence was seen 59% less after RITE than after mitomycin C (MMC) alone in adjuvant clinical setting with an overall bladder preservation rate after RITE of 85%. The efficacy was proved to be comparable to that of Bacillus Calmette-Guèrin (BCG), based on a single comparative multicentric study. Due to short follow-up, no conclusions can be drawn about time to recurrence and progression. The AE rate in RITE was higher, although not statistically significant, than MMC alone and similar to that of BCG, albeit different in the type of AE. In almost all studies, no severe AEs are reported.

Conclusions

RITE appears as a promising treatment option for NMIBC, particularly for high-risk patients with recurrent tumors, for those unsuitable for radical cystectomy and when Bacillus Calmette-Guèrin treatment is contraindicated. Further high-level evidence is needed for both reliable and reproducible data on efficacy and adverse events.

Management of carcinoma in situ of the bladder: best practice and recent developments

Management of carcinoma in situ of the bladder remains a complex and challenging endeavor due to its high rate of recurrence and progression. Although it is typically grouped with other nonmuscle invasive bladder cancers, its higher grade and aggressiveness make it a unique clinical entity. Intravesical bacillus Calmette-Guérin is the standard first-line treatment given its superiority to other agents. However, high rates of bacillus Calmette-Guérin failure highlight the need for additional therapies. Radical cystectomy has traditional been the standard second-line therapy, but additional intravesical therapies may be more appealing for non-surgical candidates and patients refusing cystectomy. The subject of this review is the treatment strategies and available therapies currently available for carcinoma in situ of the bladder. It discusses alternative intravesical treatment options for patients whose condition has failed to respond to bacillus Calmette-Guérin therapy and who are unfit or unwilling to undergo cystectomy.

The role of hyperthermia as a treatment for non-muscle invasive bladder cancer

Non-muscle invasive bladder cancer (NMIBC) has a high tendency for recurrence and progression. Currently, all known intravesical agents are associated with adverse effects (AEs) and limited efficacy. The combination of hyperthermia (HT) with intravesical Mitomycin C (MMC) chemotherapy has been shown to improve outcomes. The added efficacy of HT to MMC was first shown in preclinical studies. The reports on patients with NMIBC have indicated that the treatment is safe and well tolerated. Several clinical studies reported the efficacy of radiofrequency-induced chemotherapy effect (RITE) in the treatment of patients with NMIBC. This modality was shown to be superior to MMC alone. RITE was effective also in patients with high-risk NMIBC, including those who failed Bacillus Calmette-Guérin (BCG). This study provides an updated review of literature regarding the use of RITE in patients with NMIBC.

The effect of thermochemotherapy with mitomycin C on normal bladder urothelium, an experimental study

PURPOSE

To investigate the effects of thermochemotherapy with mitomycin C (MMC) on normal rabbit bladder urothelium and to compare it with standard intravesical MMC and hyperthermia with normal saline.

METHODS

Twenty-four male New Zealand rabbits, with a mean weight of 2.7 kg (in weight of 2.1–4.3 kg), were divided into three groups, each containing eight rabbits. Thermotherapy with only normal saline was performed in the first group, standard intravesical MMC was performed in the second group, and thermotherapy with MMC was performed in the last group. A week after the primary procedure, total cystectomy was performed and tissue samples were evaluated.

RESULTS

The presence of epithelial vacuolar degeneration (p = 0.001), epithelial hyperplasia (p = 0.000), subepithelial fibrosis (p = 0.001) and hemorrhagic areas in the connective tissue (p = 0.002) was observed statistically significantly higher in the standard MMC group than in thermotherapy with normal saline group. There was almost a significant difference among standard MMC and normal saline group in terms of vascular congestion in the connective tissue (p = 0.08). Presence of epithelial vacuolar degeneration (p = 0.002), epithelial hyperplasia (p = 0.002), subepithelial fibrosis (p = 0.030), hemorrhagic areas (p = 0.011) and vascular congestion (p = 0.36) in the connective tissue was observed statistically significantly higher in the thermochemotherapy with MMC group than in standard intravesical MMC group. Polymorphonuclear cell infiltration was not considerable in any of the groups, and there was no significant difference between each groups (p = 0.140).

CONCLUSION

Administration of intravesical MMC causes a toxic effect on the normal urothelium of the bladder rather than an inflammatory reaction. Heating MMC significantly increased this effect.

Predictive Factors for Time to Progression after Hyperthermic Mitomycin C Treatment for High-Risk Non-Muscle Invasive Urothelial Carcinoma of the Bladder: An Observational Cohort Study of 97 Patients

Introduction: Hyperthermic mitomycin (HM) is a novel treatment modality for selected patients with high-risk non-muscle invasive bladder cancer (NMIBC). We sought to determine predictors of response to this therapy. Patients and Methods: A longitudinal, cohort study of 97 patients with high-risk NMIBC treated with ≥4 HM instillations on a prophylactic schedule was conducted. The primary outcome was time-to-progression survival; secondary outcomes were overall survival, cancer-specific survival, and adverse events. Descriptive statistics, Kaplan-Meier survival analyses, Cox proportional hazards modelling, and univariate and multivariable regression were performed. Results: The presence of initial complete response (CR; no evidence of disease at first check video-cystoscopy and urine cytology) post-HM treatment was an independent predictor of good response to HM. Female patients and those without carcinoma in situ (CIS) also appeared to respond better to the intervention. The overall bladder preservation rate at a median of 27 months was 81.4%; 17/97 (17.5%) patients died during the course of the study. Conclusions: High-risk NMIBC patients can be safely treated with HM and have good oncological outcome. However, those without an initial CR have a poor prognosis and should be counselled towards adopting other treatment methodologies such as cystectomy. Female gender and lack of CIS may be good prognostic indicators for response to HM.

Efficacy and safety of a new device for intravesical thermochemotherapy in non-grade 3 BCG recurrent NMIBC: a phase I-II study

PURPOSE

We report for the first time the activity and safety of Unithermia(®) (Elmedical Ltd, Hod-Hasharon, Israel), a novel device for administration of MMC-C with hyperthermia (HT), that employs conductive heating, in a series of non-grade 3 non-muscle-invasive bladder cancer (NMIBC) that failed Bacillus Calmette-Guerin (BCG).

METHODS

Patients with non-grade 3 NMIBC recurring after at least a full induction course of BCG were eligible for this phase I-II prospective single-arm study. Six weekly instillations with Unithermia(®) were scheduled following complete TUR. Primary end points were treatment safety and response rate (RR), and the latter defined as the absence of any unfavourable outcome at 12 months. Any grade 3 and/or muscle-invasive (T > 1) recurrence was considered disease progression. Kaplan-Meier estimation of the time to recurrence and progression, cancer-specific survival and overall survival was taken as secondary end points.

RESULTS

Thirty-four eligible patients entered the study between January 2009 and April 2011. RR was documented in 20/34 (59%). Among the 14/34 (41%) non-responders, four developed G3 disease, one developed carcinoma in situ, and one progressed to muscle-invasive bladder cancer, with an overall 18% progression rate at 1 year. At a median follow-up of 41 months, recurrence and progression rates were 35.3 and 23.5%, respectively. Toxicity did not go beyond grade 2 except in five cases.

CONCLUSIONS

Initial experience with MMC-HT with Unithermia(®) showed an interesting activity and safety profile in non-grade 3 NMIBC recurring after BCG, suggesting a role as second-line therapy in this selected subgroup of NMIBC.

Intravesical mitomycin C combined with local microwave hyperthermia in non-muscle-invasive bladder cancer with increased European Organization for Research and Treatment of Cancer (EORTC) score risk of recurrence and progression

PURPOSE

To assess the activity of intravesical chemotherapy and local microwave hyperthermia (ICLMH) in increasing the disease-free interval (DFI) in patients with non-muscle-invasive bladder cancer (NMIBC) and treatment toxicity.

METHODS

Forty-two patients with a diagnosis of high-risk NMIBC, according to the European Organization for Research and Treatment of Cancer (EORTC) criteria, were treated with an intensive schedule of ICLMH using 40 mg mitomycin C. The treatment consisted of 4 weekly sessions, followed by 6 sessions delivered every 2 weeks, and by 4 monthly sessions, for a total of 14 sessions over 8 months. The DFIs before and after treatment were compared in each patient.

RESULTS

The schedule was completed as planned by 32 patients (76.2 %). The percentage of disease-free patients the year before study was 14.9 % (95 % CI 5.5-28.8) versus 88.8 % (95 % CI 73.7-94.8) after ICLMH (p < 0.0001). Patient EORTC scores, multifocality, and tumour stage were all associated significantly and independently with a higher risk of recurrence after ICLMH treatment with HR of 41.1 (p = 0.01), 17.7 (p = 0.02), and 8.5 (p = 0.02), respectively. After a median follow-up of 38 months, 24 patients (57.1 %) did not show evidence of disease, whereas 13 patients (30.9 %) underwent disease recurrence and 5 patients (11.9 %) showed also stage progression. Toxicity consisted in grades 1 and 2 frequency, non-infectious cystitis, and haematuria.

CONCLUSIONS

ICLMH significantly increases the DFI of NMIBC patients with high EORTC score for recurrence and progression. Toxicity of the intensive treatment schedule was generally mild.

Hyperthermia as adjunct to intravesical chemotherapy for bladder cancer

Nonmuscle invasive bladder cancer remains a very costly cancer to manage because of high recurrence rates requiring long-term surveillance and treatment. Emerging evidence suggests that adjunct and concurrent use of hyperthermia with intravesical chemotherapy after transurethral resection of bladder tumor further reduces recurrence risk and progression to advanced disease. Hyperthermia has both direct and immune-mediated cytotoxic effect on tumor cells including tumor growth arrest and activation of antitumor immune system cells and pathways. Concurrent heat application also acts as a sensitizer to intravesical chemotherapy agents. As such the ability to deliver hyperthermia to the focus of tumor while minimizing damage to surrounding benign tissue is of utmost importance to optimize the benefit of hyperthermia treatment. Existing chemohyperthermia devices that allow for more localized heat delivery continue to pave the way in this effort. Current investigational methods involving heat-activated drug delivery selectively to tumor cells using temperature-sensitive liposomes also offer promising ways to improve chemohyperthermia efficacy in bladder cancer while minimizing toxicity to benign tissue. This will hopefully allow more widespread use of chemohyperthermia to all bladder cancer patients, including metastatic bladder cancer.

Role of the Combined Regimen with Local Chemotherapy and Mw-Induced Hyperthermia for Non-Muscle Invasive Bladder Cancer Management. A Systematic Review

Objectives

To give an updated review concerning the role of combined regimen (CT) based on microwave-induced hyperthermia (MwHT, CT-MwHT) with intravesical chemotherapy (ICT) as a treatment for non-muscle invasive bladder cancer (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 included. The primary end-point was the time to recurrence. Secondary end-points included time to progression, bladder preservation rate, and adverse event (AE) rate.

Evidence Synthesis

A total of 24 studies met inclusion criteria and underwent data extraction. When feasible, data were combined using random-effects meta-analytic techniques. Recurrence was seen 59% less after CT-MwHT than after MMC alone, however, due to the short follow-up, no definitive conclusions can be drawn about the impact on the time to recurrence and progression. The overall bladder preservation rate after CT-MwHT was 87.6%. This rate appeared higher than after MMC alone, but valid comparison studies could not be drawn due to the absence of randomized trials in neo-adjuvant settings. AEs were higher with CT-MwHT than with MMC alone, but this difference was not statistically significant.

Conclusions

Published data suggest that recurrence rates for chemo-hyperthermia are substantially reduced compared with chemotherapy alone in adjuvant settings. Patients with refractory disease fare worse than those being treated with chemo-hyperthermia for their first tumor. Progression rates to muscle-invasive disease are markedly lower after combination treatment than after chemotherapy alone, with very high rates of bladder preservation. Tolerability is good, with few dropouts in the clinical trials. The results support CT-MwHT in the future as a standard procedure for high-risk recurrent patients, for subjects in whom the treatment with Bacillus Calmette-Guérin is contraindicated, and those unsuitable for radical cystectomy.

[Recurrent bladder cancer after BCG instillation therapy. Local therapy options?]

Patients with a so-called BCG failure (Bacillus Calmette-Guérin) constitute an inhomogeneous group of patients. Patients with BCG recurrence or BCG refractive tumors are real BCG failures. Therapeutic options are radical cystectomy and a conservative approach, depending on the individual risk of recurrence and progression. Intravesical chemotherapy with docetaxel or gemcitabine after BCG failure shows some promise whereas second line immunotherapy, the combination of BCG and interferon (INF)-α, is an effective regimen but results need to be confirmed. Device-assisted intravesical strategies, such as mitomycin-EMDA or chemohyperthermia are candidates to keep in mind for the near future. Finally, cystectomy results in the best disease-specific survival in patients with BCG failure.

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.