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Intravesical therapy with bacillus Calmette-Guérin has proven effects for reducing recurrence, progression, and death from non-muscle-invasive bladder cancer. These advantages are seen mainly when appropriate maintenance therapy is used for 1-3 years, in the context of appropriate patient selection, tumor management, and symptom support for potential side effects.

Abstract: Background: Cannabinoid receptor (CB)–mediated functions may be involved in the regulation of bladder function, but information on endocannabinoid signals during micturition is scarce. Objective: Investigate the expression of the endocannabinoid-degrading enzyme fatty acid amide hydrolase (FAAH) in human, rat, and mouse bladders and study the effects of inhibition of FAAH during urodynamics in awake rats. Design, setting, and participants: Bladder tissue from humans, mice, and rats was used for measurements. Female Sprague-Dawley rats were administered the FAAH inhibitor oleoyl ethyl amide (OEtA) or vehicle intravenously (IV) or intravesically (IVES) with or without rimonabant (CB1 antagonist) or SR144528 (CB2 antagonist). Measurements: Real-time transcriptase-polymerase chain reaction, Western blot, immunohistochemistry, and cystometry in awake rats. Results and limitations: Messenger RNA and protein for FAAH was expressed in the mucosa of human, mouse, and rat urinary bladders. Immunoreactivities for FAAH and CB2 were codistributed in rat and human urothelium. IV OEtA (0.3mg/kg) to rats increased intercontraction intervals (ICIs), micturition volume (MV), bladder capacity (BC), and threshold pressure (TP) by 17±1%, 16±1%, 17±1%, and 19±5%, respectively (all p <0.05 vs baseline). IVES OEtA (1 and 10mg/l) in rats dose-dependently increased (p <0.05 vs baseline) ICI (19±2% and 35±5%), MV (15±3% and 32±4%), BC (16±2% and 34±4%), and TP (15±1%, 21±3%). SR144528 (IVES 5mg/l) abolished all effects of OEtA, whereas rimonabant only counteracted effects of OEtA on TP. Conclusions: Bladder mucosa of all species expressed FAAH. Rat and human urothelium coexpressed FAAH and CB2. The FAAH inhibitor OEtA altered urodynamic parameters that reflect sensory functions of micturition in rats. Suggesting a role for the endocannabinoid system in bladder mechanoafferent functions of rats, effects of IVES OEtA were abolished by an IVES CB2 antagonist and partly counteracted by an IVES CB1 antagonist. [Copyright &y& Elsevier]

Abstract: Background: Gonadotropin-releasing hormone (GnRH) antagonists have been reported to have beneficial effects on lower urinary tract symptoms in patients with benign prostatic hyperplasia. Objective: Our aim was to investigate the effects of ganirelix, a GnRH receptor antagonist, on bladder function and detrusor overactivity (DO) in female rats. Design, setting, and participants: Female Sprague-Dawley rats received 2 wk of daily systemic (0.1mg/kg) or acute intravesical administration (IVES; 0.14mg/l or 1.4mg/l) ganirelix or vehicle (controls). Measurements: Assessments were obtained using cystometry in awake rats, organ bath studies, enzyme-linked immunosorbent assay, and western blot (WB). Results and limitations: Luteinising hormone levels were lower in rats treated systemically with ganirelix than in controls. No differences were observed in body or bladder weights. Micturition interval (MI), micturition volume (MV), residual volume, and bladder capacity (BC) were similar in both groups at baseline. No differences in urodynamic pressure parameters were observed between groups at baseline. Intravesical prostaglandin E2 reduced MI, MV, and BC, and it increased basal pressure (BP), threshold pressure (TP), flow pressure (FP), and maximum pressure (MP) in all rats. MI, MV, and BC were reduced by 43%±4%, 50%±4%, and 43%±4% (controls) versus 22%±3%, 23%±3%, and 21%±3% (ganirelix-treated rats; p <0.001). TP and FP increased by 38%±8% and 30%±4% (controls) versus 16%±7% and 16%±5% (ganirelix; p <0.05). The maximal force of contractions for carbachol was larger in detrusor from ganirelix-treated rats (231% vs 177% of 60mM K+-induced contractions). At 0.14mg/l, but not 0.14mg/l, IVES ganirelix increased MI, MV, and BC and decreased BP, TP, FP, and MP. In vitro, ganirelix had no effect on detrusor function. The gonadotropin-releasing hormone receptor was expressed (by WB) in the bladder mucosa. Conclusions: Systemic treatment with ganirelix counteracted experimental DO in female rats. Because bladder preparations from these rats exhibited larger contractions to carbachol and because intravesical ganirelix affected both micturition intervals and urodynamic pressure profiles, a peripheral site of action of ganirelix in the urinary bladder cannot be excluded. [Copyright &y& Elsevier]

Abstract: Context: Bacillus Calmette-Guérin (BCG) remains the most effective intravesical treatment for non–muscle-invasive bladder cancer (NMIBC), but the clinical development of BCG has been accompanied by controversy. Recent publications have called into question a number of aspects related to its use. Objective: To review the current clinical role of BCG in NMIBC, focusing on efficacy and tolerability as primary objectives and on strategies to predict response and decrease toxicity as secondary objectives. Evidence acquisition: We performed a systematic literature search of published articles in PubMed, Embase, and the Cochrane Central Register of Controlled Trials databases for the period from 1976 to November 2008. The following “free text” combination was used in the first instance: “BCG and intravesical and bladder cancer.” Further free text searches were performed by separately adding the following keywords to the combination “BCG and intravesical”: survival, progression, recurrence, maintenance, dosing, toxicity, tolerability, side effects, prognostic factors. Evidence synthesis: BCG is the most effective intravesical agent for preventing NMIBC recurrence, but its role in disease progression remains controversial. In intermediate-risk NMIBC, the superiority of BCG over chemotherapy is well established for disease recurrence but not for progression and needs to be balanced against higher toxicity. With regard to high-risk NMIBC, there is sufficient evidence to show that BCG is the most effective treatment of carcinoma in situ for ablation, disease-free interval, and progression, but the impact of BCG on the natural history of T1G3 tumors relies on a low level of evidence. Maintenance remains crucial for efficacy. The dose can be safely and effectively reduced to decrease its toxicity, which is slightly greater than chemotherapy. Conclusions: BCG should still be viewed as the most effective intravesical agent, but its role in the progression of papillary tumors needs to be clarified. BCG remains an alternative to intravesical chemotherapy in intermediate-risk NMIBC, and it is recommended as the standard of care for high-risk NMIBC. [Copyright &y& Elsevier]

Abstract: Background: The exact mechanisms of action of intravesical electrical stimulation (IVES) are not yet fully understood. Objective: To gain more insight into the underlying mechanism(s) of the direct detrusor response during IVES by transsecting the dorsal roots and the pelvic nerve consecutively at different levels and to determine whether the efficiency of IVES to induce contraction could be enhanced by simultaneous bladder filling and IVES and by changing the bladder-filling grade. Design, Setting, and Participants: Eighteen Sprague-Dawley rats underwent IVES (square-wave pulses at 10Hz, 20-ms pulse duration). Measurements: In seven rats, IVES-induced bladder-pressure development was studied after the bladder nerves were consecutively sectioned bilaterally at four different levels: no lesion, L6 dorsal roots, L6 ventral roots, pelvic nerve, and major pelvic ganglion with surrounding nerves. Bladder-pressure development induced by IVES with simultaneous bladder filling, by bladder filling alone, and by IVES alone was recorded in seven other rats, and bladder-pressure development induced by IVES with different grades of bladder filling was recorded in four rats. Results and Limitations: Contraction during IVES was significantly weaker after consecutive section of more nerves (all p <0.001), but a small contraction (19±17% of baseline) could be elicited even after total decentralization. In the neurologically intact rats, separate stimulation and bladder filling gave contraction strengths similar to those of simultaneous bladder filling and stimulation, but the latter gave contraction after a significantly shorter stimulation time (both p <0.015). Conclusions: IVES-induced contraction is, for the major part, a nerve-mediated process. However, a small bladder-pressure rise was induced by direct bladder-wall stimulation after all nerves were cut. Simultaneous electrical stimulation and bladder filling needed much shorter stimulation times than bladder filling alone or stimulation alone. If confirmed in humans, this could shorten IVES sessions substantially without altering the contractile results and could indicate that summation of afferent potentials from different triggers is possible. [Copyright &y& Elsevier]

Objective: Phase I studies have so far demonstrated that intravesical Gemcitabine up to a 40 mg/ml concentration is well tolerated and has a substantial ablative activity on high-risk BCG refractory SBC. New treatment options are needed for intermediate-risk SBC recurring after conventional intravesical treatments. The purpose of the present study was to investigate the ablative efficacy of intravesical Gemcitabine on intermediate-risk SBC.Methods: The study was designed as a two-stage phase II trial, with a sample size of 39 patients. The efficacy of intravesical Gemcitabine at a concentration of 40 mg/ml (2000 mg in 50 ml saline solution) administered weekly for 6 weeks was assessed on a single marker tumour left in the bladder after a complete TUR of all other lesions. Patients underwent TUR or biopsy at the site of the marker lesion 2 weeks after completion of the treatment.Results: Complete response was observed in 22 out of 39 patients (56%). No progression was observed among the 17 non-responders. Neither systemic nor local side effects generally exceeded grade I toxicity.Conclusion: The ablative effect of Gemcitabine produced a higher number of responses than the minimum required by the protocol to indicate a significant probability of drug efficacy. It is worth testing the drug in phase III trials to assess for durability of response. [Copyright &y& Elsevier]