Harm C. Arentsen

Hexaminolevulinate-Guided Fluorescence Cystoscopy in the Diagnosis and Follow-Up of Patients with Non–Muscle-Invasive Bladder Cancer: Review of the Evidence and Recommendations

CONTEXT Compared with standard white-light cystoscopy, photodynamic diagnosis with blue light and the photosensitiser hexaminolevulinate has been shown to improve the visualisation of bladder tumours, reduce residual tumour rates by at least 20%, and improve recurrence-free survival. There is currently no overall European consensus outlining specifically where hexaminolevulinate is or is not indicated. OBJECTIVE Our aim was to define specific indications for hexaminolevulinate-guided fluorescence cystoscopy in the diagnosis and management of non-muscle-invasive bladder cancer (NMIBC). EVIDENCE ACQUISITION A European expert panel was convened to review the evidence for hexaminolevulinate-guided fluorescence cystoscopy in the diagnosis and management of NMIBC (identified through a PubMed MESH search) and available guidelines from across Europe. On the basis of this information and drawing on the extensive clinical experience of the panel, specific indications for the technique were then identified through discussion. EVIDENCE SYNTHESIS The panel recommends that hexaminolevulinate-guided fluorescence cystoscopy be used to aid diagnosis at initial transurethral resection following suspicion of bladder cancer and in patients with positive urine cytology but negative white-light cystoscopy for the assessment of tumour recurrences in patients not previously assessed with hexaminolevulinate, in the initial follow-up of patients with carcinoma in situ (CIS) or multifocal tumours, and as a teaching tool. The panel does not currently recommend the use of hexaminolevulinate-guided fluorescence cystoscopy in patients for whom cystectomy is indicated or for use in the outpatient setting with flexible cystoscopy. CONCLUSIONS Evidence is available to support the use of hexaminolevulinate-guided fluorescence cystoscopy in a range of indications, as endorsed by an expert panel.

Results of a Phase 1 Dose Escalation Study of Intravesical TMX-101 in Patients with Nonmuscle Invasive Bladder Cancer

PURPOSE Imiquimod, a toll like receptor 7 (TLR-7) agonist, is effective as a topical treatment for skin malignancies. TMX-101 is a liquid formulation of imiquimod. In this study we establish a safety profile of TMX-101 in patients with nonmuscle invasive bladder cancer. MATERIALS AND METHODS We conducted a multicenter phase 1 dose escalation study in patients with nonmuscle invasive bladder cancer. Patients were included in 1 of 4 dose groups (0.05%, 0.1%, 0.2% or 0.4%) and treated with 6 weekly instillations of TMX-101, starting 2 weeks after transurethral resection of bladder tumor. Patients were evaluated weekly, and pharmacokinetic and pharmacodynamic parameters were measured. RESULTS A total of 16 patients were included in the study with 4 per dose group. Two patients dropped out after instillation 2 in dose groups 1 and 2. Overall, 88 instillations were administered without serious adverse events. There were 118 adverse events, of which 84 were related to the study drug. All adverse events were mild or moderate and number or severity was not correlated with dose group. Of the related adverse events 70% were confined to the genitourinary tract and resolved without intervention. There was a dose dependent systemic uptake with low plasma levels up to dose group 3 (0.2%, 100 mg). Maximum plasma concentration in dose group 4 (0.4%, 200 mg) was 71.7 ng/ml. This is below plasma concentrations of 123 and 128 ng/ml without significant side effects measured in healthy volunteers after subcutaneous (30 mg) or oral intake (100 mg) of imiquimod, respectively. CONCLUSIONS Intravesical treatment with TMX-101 is safe. The side effects are common but mild and mostly limited to the genitourinary tract. There is a low systemic uptake.

Phase 2 Study of Adjuvant Intravesical Instillations of Apaziquone for High Risk Nonmuscle Invasive Bladder Cancer

PURPOSE We studied the safety and efficacy of multiple adjuvant apaziquone instillations in patients with high risk nonmuscle invasive bladder cancer. MATERIALS AND METHODS Patients with high risk nonmuscle invasive urothelial carcinoma of the bladder underwent transurethral resection of all bladder tumor(s), and received 6 weekly adjuvant intravesical apaziquone instillations of 4 mg in 40 ml. Patients with carcinoma in situ received 3 further maintenance instillations at months 3, 6 and 12. Followup consisted of cystoscopy, urine cytology and observation of adverse events every 3 months for 18 months. RESULTS A total of 53 patients were enrolled in the study. Although all patients were high risk according to the definitions used when the study was initiated, according to most recent guideline criteria, 80% and 20% of these patients would now be considered intermediate and high risk for recurrence, and 50% and 44% would be considered intermediate and high risk for progression, respectively. Intent to treat analysis of 49 patients with papillary tumors showed recurrent tumors in 34.7% and 44.9% at 12 and 18 months, respectively. One patient had progression to T2 or greater urothelial carcinoma after 9 months. There were 4 patients with carcinoma in situ who had complete responses at 3 months but discontinued treatment due to cystitis, recurrent papillary disease, urinary incontinence and dysuria. Most other side effects were mild (grade 1 to 2). CONCLUSIONS Adjuvant intravesical instillations of apaziquone are generally well tolerated. The recurrence rates of 34.7% after 12 months and 44.9% after 18 months in these patients can be considered encouraging, and warrant further study.

Experimental rat bladder urothelial cell carcinoma models

Bladder cancer is a major public health problem. Currently available therapeutic options seem to be unable to prevent bladder cancer recurrence and progression. To enable preclinical testing of new intravesical therapeutic agents, a suitable bladder tumor model that resembles human disease is highly desirable. The aim of this topic paper was to discuss the problems associated with current in vivo animal bladder tumor models, focusing on the orthotopic syngeneic rat bladder tumor model. In the second part of the paper the development of a potential new orthotopic rat bladder tumor model is described.

Pharmacokinetics and toxicity of intravesical TMX-101: a preclinical study in pigs.

• To study the pharmacokinetic and toxicity profile of intravesically administered TMX‐101, with its active ingredient R‐837, a synthetic Toll‐like receptor (TLR)‐7 agonist, in a pig model.

The effect of photochemical internalization of bleomycin in the treatment of urothelial carcinoma of the bladder: An in vitro study

OBJECTIVES In this in vitro study, we determined whether meso-tetraphenyl chlorin disulphonate (TPCS2a)-based photochemical delivery of bleomycin was able to potentiate the cytotoxicity of bleomycin on bladder cancer cells. MATERIALS AND METHODS The human RT4, RT112, 253J, T24, and rat AY-27 urothelial carcinoma cell lines were used. Cells were seeded in 96-well plates. TPCS2a was added to the growth medium and the plates were incubated overnight. Cells were then resuspended in TPCS2a-free culture medium and incubated for 3 hours. Subsequently, cells were treated for 60 minutes with increasing doses of epirubicin, gemcitabine, mitomycin C, or bleomycin followed by illumination for different periods. Cell viability was measured with a colorimetric assay after 72 hours. RESULTS For the single treatments, in all 5 cell lines a dose-dependent inhibition of cell proliferation was observed. This was seen both after treatment with TPCS2a-based photodynamic therapy (PDT), as well as after treatment with either bleomycin or one of the control chemotherapeutic agents. After treatment with PDT (240-s illumination), bleomycin 9.0 µM, and the combination of these treatments, relative survival percentages were 89.2 ± 13.0, 70.2 ± 8.9, and 30.5 ± 6.1, respectively, in the T24 cell line. After treatment with PDT (120-s illumination), bleomycin 27 µM and the combination of these treatments, relative survival percentages were 93.6 ± 15.7, 74.7 ± 9.6, and 30.0 ± 11.1, respectively, in the AY-27 cell line. In both cell lines, PDT combined with bleomycin showed significantly (P<0.001) higher cell kill than the sum of the single treatments, suggesting a photochemical internalization effect. CONCLUSIONS TPCS2a-based photochemical internalization of bleomycin showed a significant, at least, additive antiproliferative activity against human and rat urothelial carcinoma cells in vitro. Thus, photochemical internalization may have therapeutic potential as an intravesical strategy against bladder cancer. As the effect is heterogeneous, biomarker studies are warranted to be able to predict the effects of a photochemical internalization-based treatment.

Antitumor Effects of cis-Urocanic Acid on Experimental Urothelial Cell Carcinoma of the Bladder

PURPOSE We determined the effect of protodynamic therapy against bladder cancer cells in vitro and in vivo. We investigated cis-urocanic acid in rat bladder cancer cell cultures and in an orthotopic rat urothelial carcinoma model to assess its safety and antiproliferative activity. MATERIALS AND METHODS The rat bladder cancer cell line AY-27 was exposed to cis-urocanic acid (BioCis Pharma, Turku, Finland) at pH 6.5 or 7.4 for 2 hours. Cell viability was measured by colorimetric assay at 24 and 48 hours. For in vivo experiments AY-27 cells were instilled into the acid treated bladder of 17 rats. After 4, 7 and 10 days 14 rats were treated intravesically with cis-urocanic acid 6% (weight per volume) or vehicle. Rats were sacrificed on day 12 and the bladders were dissected. Immunohistochemical staining was done to assess apoptosis (caspase-3) and cell proliferation (Ki-67) in vivo. RESULTS Cis-urocanic acid caused dose dependent, pH dependent inhibition of AY-27 cell proliferation, showing the protodynamic action at concentrations of 0.5% and 1%. At higher cis-urocanic acid doses complete cell death was observed. All tumors detected in animals treated with vehicle were muscle invasive (stage T2 or greater) but only 43% of tumors were muscle invasive in the cis-urocanic acid treated group (p=0.049). There was no difference in the percent of apoptotic or proliferating tumor cells between treatment groups. No signs of toxicity were observed. CONCLUSIONS Cis-urocanic acid showed direct antiproliferative activity against rat bladder cancer cells in vitro and antitumor effects in vivo. It may have therapeutic potential as an intravesical agent for nonmuscle invasive bladder cancer.

Management of Low-risk and Intermediate-risk Non–Muscle-invasive Bladder Carcinoma

Non-muscle-invasive bladder cancer is a highly recurrent disease. The health care costs for non-muscle-invasive bladder cancer are a major burden for society. Bladder cancer treatment starts with a presumed complete transurethral resection of a bladder tumor. Despite international guidelines for perioperative and/or adjuvant intravesical instillation therapy in non-muscle-invasive bladder cancer, adequate worldwide application is lacking. In patients who do get adjuvant intravesical instillations, recurrences are still frequent. New therapies in non-muscle-invasive bladder cancer are unsatisfactory and still experimental.

The orthotopic Fischer/AY-27 rat bladder urothelial cell carcinoma model to test the efficacy of different apaziquone formulations

OBJECTIVES Apaziquone used intravesically showed significant activity in phase I and II marker lesion studies in non-muscle-invasive bladder cancer. The objective of this study was to assess antitumor activity and safety of 3 different formulations of intravesical apaziquone in an orthotopic rat bladder cancer model. MATERIALS AND METHODS Female Fischer F344 rats were instilled with 1.5 × 10(6) AY-27 urothelial cell carcinoma cells and divided in 3 treatment groups (n = 10) and 1 placebo group (n = 6). Intravesical treatment was administered for 1 hour on days 2 and 5. Rats were treated with apaziquone in the formulation used in phase I/II clinical trials (group 1); apaziquone with an altered buffering capacity being used in phase III clinical trials (group 2), and apaziquone as in group 2, but without propylene glycol in the diluent (group 3). On days 5 and 14, the bladder wall was inspected by cystoscopy and evaluated for macroscopic tumor growth. After sacrificing the rats (day 14), cystectomy was performed and the bladders were investigated. RESULTS There were no signs of any toxicity due to the study drug. On histopathologic examination of the bladders 0, 1, and 2 tumors per group were found in group 1, 2, and 3, respectively. In the placebo-treated group, 60% of animals developed tumor, which is comparable to untreated animals. CONCLUSIONS Apaziquone showed an excellent antitumor activity. The effectiveness of apaziquone in this orthotopic rat bladder tumor model corroborates the clinical observations and implies the validity of this model.

Resultaten van een fase 1-dosisescalatiestudie naar intravesicale behandeling met TMX-101 bij patiënten met een niet-spierinvasief blaascarcinoom

Introductie De huidige behandeling van het niet-spierinvasief blaascarcinoom (NSIBC) is suboptimaal, getuige de hoge kans op recidieven en/of progressie. TMX-101 is een formulering van imiquimod, geschikt voor intravesicale instillatie. Imiquimod is een Toll-Like-Receptor (TLR)-7 agonist met een immunomodulerende werking. TLR-7-agonisten worden klinisch succesvol gebruikt als topicale behandeling van huidmaligniteiten en hebben een antiproliferatief effect op urotheelcarcinomen in vitro en in vivo. In deze fase 1-dosisescalatiestudie onderzoeken we de veiligheid van intravesicale behandeling met TMX101.