The effects of intravesical chemoimmunotherapy with gemcitabine and Bacillus Calmette-Guérin in superficial bladder cancer: a preliminary study

Urease-Powered Polydopamine Nanomotors for Intravesical Therapy of Bladder Diseases

Intravesical therapeutic delivery has been extensively investigated for various bladder diseases such as bladder cancer, overactive bladder, urinary incontinence, and interstitial cystitis. However, conventional drug carriers have a low therapeutic delivery efficiency because of the passive diffusion of drug molecules in a bladder and the rapid clearance by periodic urination. Here, we report biocompatible and bioavailable enzyme-powered polymer nanomotors which can deeply penetrate into a mucosa layer of the bladder wall and remain for a long-term period in the bladder. The successful fabrication of nanomotors was confirmed by high-resolution transmission electron microscopy, energy-dispersive X-ray mapping, zeta-potential analysis, Fourier transform infrared spectroscopy, and urease activity and nanomotor trajectory analyses. After injection into the bladder, urease-immobilized nanomotors became active, moving around in the bladder by converting urea into carbon dioxide and ammonia. The nanomotors resulted in the facilitated penetration to the mucosa layer of the bladder wall and the prolonged retention in the bladder even after repeated urination. The enhanced penetration and retention of the nanomotors as a drug delivery carrier in the bladder would be successfully harnessed for treating a variety of bladder diseases.

The role of single instillation chemotherapy in patients who receive subsequent bacillus Calmette-Guérin: A retrospective single centre study, and systematic review of the literature

INTRODUCTION

This retrospective study was undertaken to evaluate the combined effect of immediate intravesical chemotherapy and subsequent bacillus Calmette-Guérin (BCG) therapy.

METHODS

The study population consisted of 207 intermediate- or high-risk patients with non-muscle invasive bladder cancer who underwent an induction course of BCG between 1993 and 2007. We introduced single immediate instillation of 50 mg epirubicin for all cases in 2004, and thus earlier cases could be considered as historical controls. The primary endpoint was recurrence-free survival (RFS). For cumulative analysis, we systematically reviewed studies indexed in databases. Including ours, the records of 856 patients from a total of 7 studies, including ours, were finally analyzed.

RESULTS

In our cohort, the 5-year RFS in patients who received the combination therapy was 66.2%, compared to 55.2% in the BCG alone group (p = 0.149). Multivariate analysis on tumour recurrence showed that patients with the combination therapy had a hazard ratio (HR) of 0.74 (p = 0.189). A subsequent literature review revealed that RFS rates in the combination groups were higher than those in the corresponding BCG alone groups in 4/7 studies (p = 0.02-0.15), and lower in 1 study (p = 0.51). We identified 5 studies which examined a HR for combination therapy, and performed a cumulative analysis. Adding a single chemo-instillation prior to BCG resulted in a significant reduction in tumour recurrence (summary HR 0.69, p = 0.010).

CONCLUSIONS

Our analysis suggested that the combination of single chemo-instillation with subsequent BCG therapy exhibited an additive effect against potential tumour recurrence.

Can intravesical bacillus Calmette-Guérin reduce recurrence in patients with non-muscle invasive bladder cancer? An update and cumulative meta-analysis

Approximately 70% of newly diagnosed bladder tumors are non-muscle invasive bladder cancer (NMIBC). NMIBC accounts for approximately 80% of total bladder cancer cases. Bacillus Calmette-Guérin (BCG) instillation and maintenance is considered as the standard adjuvant treatment for superficial bladder cancer. A number of randomized studies have focused on the benefit of maintenance therapy following initial BCG induction. To provide further insights into the effect of intravesical instillation on recurrence in patients with NMIBC, we analyzed this relationship by conducting an updated detailed meta-analysis. Evidence suggested that adjuvant intravesical BCG with maintenance treatment is significantly effective for the prophylaxis of tumor recurrence in patients with NMIBC.

Multi-institutional analysis of sequential intravesical gemcitabine and mitomycin C chemotherapy for non-muscle invasive bladder cancer

OBJECTIVE

Apart from cystectomy, few treatment options exist for the management of bacillus Calmette-Guerin refractory non-muscle invasive bladder cancer (NMIBC). We report a multi-institutional experience with sequential intravesical combination chemotherapy using gemcitabine and mitomycin C (MMC) for NMIBC in the treatment of high-risk patients.

METHODS

We performed a retrospective review of patients who received 6 weekly treatments with sequential intravesical gemcitabine (1g) and MMC (40 mg) chemotherapy for NMIBC. Gemcitabine was administered first and retained for 90 minutes and then drained. MMC was then administered directly after and retained for an additional 90 minutes. Forty-seven patients received treatment from 3 academic tertiary referral centers between 2000 and 2010.

RESULTS

Forty-seven patients (median age 70, range 32-85; 36 males, 11 females) who previously failed a median of 2 intravesical treatments were reviewed. Complete response, 1-year, and 2-year recurrence-free survival rates for all patients were 68%, 48%, and 38%, respectively. Median recurrence-free survival for all patients was 9 months (range 1-80). Fourteen of 47 patients (30%) remained free of recurrence with a median time to follow-up of 26 months (range 6-80 mo). Ten patients required cystectomy.

CONCLUSION

Sequential intravesical combination chemotherapy using gemcitabine and MMC appears to be a useful treatment for patients with high-grade NMIBC as well as those with prior bacillus Calmette-Guerin failure. Further prospective studies are warranted.

Intravesical gemcitabine for non-muscle invasive bladder cancer

BACKGROUND

Intravesical immunotherapy or chemotherapy for non-muscle invasive bladder cancer is a well established treatment for preventing or delaying tumour recurrence following tumour resection. However, up to 70% of patients may fail and new intravesical agents with improved effectiveness are needed. Gemcitabine is a relatively new anticancer drug that has shown activity against bladder cancer.

OBJECTIVES

To evaluate the effectiveness and toxicity of intravesical gemcitabine in preventing tumour recurrence and progression in non-muscle invasive bladder cancer (NMIBC).

SEARCH METHODS

A search strategy was developed for MEDLINE to identify randomised trials of intravesical gemcitabine for the treatment of non-muscle invasive bladder cancer. The searches were from 1947 to May 2011. Other databases searched included EMBASE, CINAHL, the Cochrane Central Register of Controlled Trials, LILACS, SCOPUS, BNI, Biomed Central, Web of Science and BIOSIS. Handsearching of meeting proceedings, international guidelines and trial registries was also carried out.

SELECTION CRITERIA

The titles and abstracts of the combined electronic and handsearching were manually screened by three authors independently to determine if they met the inclusion criteria for this review. Studies were selected if they were randomised, controlled trials or quasi-randomised clinical trials that included intravesical gemcitabine in at least one arm of a comparative study.

DATA COLLECTION AND ANALYSIS

Data extraction was carried out by three reviewers. The information retrieved included the author's details, the study design, the characteristics of the recruited patients, details of the interventions and data relating to the primary, and secondary outcome measures.

MAIN RESULTS

Six relevant randomised trials were identified with the number of patients randomised in each trial varying from 30 to 341 (total 704). All trials compared gemcitabine to active controls and varied in the reporting of outcomes. One study compared a single post-operative instillation of intravesical gemcitabine with a saline placebo in 341 patients and found no significant difference in the rates of tumour recurrence (28% versus 39%, respectively) or recurrence-free survival (HR (hazard ratio) 0.95, 95% CI 0.64 to1.39, P = 0.77). The rate of progression to invasive disease was greater with gemcitabine (2.4% versus 0.8%). A further trial compared gemcitabine with intravesical mitomycin C and demonstrated that the rates of recurrence (28% versus 39%) and progression (11% versus 18%) were lower with gemcitabine but did not reach statistical significance. The global incidence of adverse events was significantly less with gemcitabine (38.8% versus 72.2%, P = 0.02).Three trials compared gemcitabine with intravesical BCG but a meta-analysis was not possible due to clinical heterogeneity. In untreated patients at intermediate risk of recurrence (primary Ta-T1 no CIS) one trial showed that gemcitabine and BCG were similar with respective recurrence rates of 25% and 30% (P = 0.92) and overall progression equal (P = 1.0). Dysuria (12.5% versus 45%, P < 0.05) and frequency (10% versus 45%, P < 0.001) were significantly less with gemcitabine. In a second trial of high risk patients the recurrence rate was significantly greater with gemcitabine compared to BCG (53.1% and 28.1%, P = 0.04) and the time to recurrence significantly shorter with gemcitabine (25.5 versus 39.4 months, P = 0.042). Finally in a third trial of high risk patients who had failed previous intravesical BCG therapy, gemcitabine was associated with significantly fewer recurrences (52.5% versus 87.5%, P = 0.002) and a longer time to recurrence (3.9 versus 3.1 months, P = 0.9) compared to BCG. Progression rates were similar in both groups (33% versus 37.5%, P = 0.12) with no significant differences in grade 2 or 3 toxicities.The final trial was a marker lesion study which reported greater response rates when intravesical gemcitabine (2 g) was given as three bi-weekly doses (36%) or six weekly doses (40%) compared to a single dose (9%).

AUTHORS' CONCLUSIONS

A single dose immediately following surgery is ineffective based on one study. Gemcitabine may be more active than mitomycin C with a lower toxicity profile. Compared to intravesical BCG therapy, gemcitabine had similar effects in intermediate risk patients, less effective in high risk patient and superior in BCG refractory patients. However, each randomised trial identified represents a different clinical setting in NMIBC and therefore the evidence base is limited. Consequently these data should be interpreted with caution until further corroborative evidence becomes available. The aim of intravesical therapy in NMIBC is to prevent tumour recurrence and progression and to avoid the morbidity associated with cystectomy. Intravesical gemcitabine is a promising drug that may add to the urologist's options in achieving this goal.