Evaluation of a low-dose intravesical bacillus Calmette-Guérin (Tokyo strain) therapy for superficial bladder cancer

Intravesical bacillus Calmette-Guérin for bladder cancer: are all the strains equal?

Intravesical immunotherapy with bacillus Calmette-Guérin (BCG) is the standard of care for high-risk and intermediate-risk non-muscle-invasive bladder cancer (NMIBC). Several BCG strains are available. Despite originating all from subcultures of the same Mycobacterium, strains are genetically different which may lead to differences in treatment efficacy and adverse events. Identification of a more efficient strain and assessing its optimal administration schedule may improve oncological outcomes in NMIBC, specifically because of the worldwide shortage in BCG availability. This review focused on the antitumor effect of different BCG strains with a particular emphasis on the evidence underlying BCG dose and treatment schedules.

Prophylactic effects of Bacille Calmette-Guérin intravesical instillation therapy: time period-related comparison between Japan and Western countries

Guidelines change every few years regarding the prophylactic use of Bacille Calmette-Guérin (BCG) against non-muscle invasive bladder cancer. We performed a retrospective comparison to clarify the differences in BCG efficacy, based on time period, between Japan and Western countries . Published literature on 18 Japanese and 28 Western patient studies were compared to evaluate differences in BCG efficacy. Additionally, Internet searches were performed to obtain comparative Japanese and Western data. BCG efficacy in Japanese literature tended to show decreasing non-recurrence rates by time period. Non-recurrence rates in Western countries increased each year. This discrepancy may stem from a number of factors, including changes in accepted BCG indications, the introduction of restaging transurethral resection (re-TUR), the concept of BCG maintenance, and the evolution of histopathological diagnostic criteria.

Optimal schedule of bacillus calmette-guerin for non-muscle-invasive bladder cancer: a meta-analysis of comparative studies

Background

To explore the necessity of maintenance, efficacy of low-dose and superiority of various combination therapies of Bacillus Calmette-Guérin (BCG) in treatment of superficial bladder cancer (BCa).

Methods

Comprehensive searches of electronic databases (PubMed, Embase, and the Cochrane Library) were performed, then a systematic review and cumulative meta-analysis of 21 randomized controlled trials (RCTs) and 9 retrospective comparative studies were carried out according to predefined inclusion criteria.

Results

Significantly better recurrence-free survivals (RFS) were observed respectively in patients who received BCG maintenance, standard-dose and BCG plus epirubicin therapy comparing to those received induction, low-dose and BCG alone. BCG maintenance therapy was also associated with significantly better progression-free survival (PFS), but there were more incidences of adverse events. Pooled results showed no remarkable advantage of BCG combined with Mitomycin C or with interferon α-2b in improving oncologic outcomes. Sensitivity-analyses stratified by study-design and tumor stage led to very similar overall results and often to a decrease of the between-study heterogeneity. Our data confirmed that non-RCT only affected strength rather than direction of the overall results.

Conclusions

All patients with superficial BCa should be encouraged to accept BCG maintenance therapy with standard-dose if well tolerated. Patients can benefit from BCG combined with epirubicin but not from BCG combined with Mitomycin C or interferon α-2b.

Weekly intravesical bacillus Calmette-Guerin (BCG) alternating with epirubicin in Ta and T1 urothelial bladder cancer: An approach to decrease BCG toxicity

Context:

Bacillus Calmette-Guerin (BCG) therapy is the standard treatment for nonmuscle-invasive bladder cancer (NMIBC). However, its toxicity is a major concern.

Aim:

If we reduce the number of BCG doses by half and replace the second half with epirubicin, we may have a lower toxicity while maintaining the same efficacy of BCG. To test this hypothesis, we conducted this study as an update of our previous report.

Setting and Design:

The study included 607 patients with Ta and T1 NMIBC between January 1994 and December 2008.

Materials and Methods:

After transurethral resection of bladder tumor (TURBT), the patients received weekly doses of 120 mg BCG alternating with 50 mg epirubicin for six weeks (three weekly doses of each). Maintenance was given. Recurrence, progression rates, and toxicity were assessed. End points were progression, recurrence, and cancer-specific survival.

Results:

A total of 532 patients were eligible for evaluation (mean age: 58 years; median follow-up: 45 months). Of these, 291 (55%) were free, 157 (29.5%) showed recurrence, and 84 (15.8%) showed muscle-invasive progression. Toxicity developed in 221 patients. These were mild in the majority (167), whereas 10 developed hematuria, 30 severe cystitis, and five systemic complications. The rate of permanent therapy discontinuation was 3.8%.

Statistical Analysis Used:

SPSS package version 16 and Kaplan-Meier curves were used to evaluate survival.

Conclusions:

Reducing the frequency of BCG instillations by half and replacing the second half with epirubicin results in a similar efficacy and a lower toxicity compared with historical cases receiving BCG alone. However, further trials are required to support these results.

Comparable effect with minimal morbidity of low-dose Tokyo 172 strain compared with regular dose Connaught strain as an intravesical bacillus Calmette-Guérin prophylaxis in nonmuscle invasive bladder cancer: Results of a randomized prospective comparison

AIM

The aim was to compare patients' morbidity and response of bacillus Calmette-Guérin (BCG) prophylaxis after the intravesical instillation of low-dose Tokyo 172 strain and regular dose Connaught strain in patients with nonmuscle invasive bladder cancer (NMIBC).

PATIENTS AND METHODS

This was a randomized, active-controlled, open-label, monocenter study. Thirty-eight, NMIBC patients were treated sequentially, in a random order, with low-dose Tokyo 172 strain and regular dose Connaught strain, receiving each therapy for 6 weeks. A total of 18 and 20 patients were randomly assigned to a Tokyo 172 strain arm and a Connaught strain arm, respectively. Complication, morbidity, and recurrence-free survival (RFS) after each treatment were compared.

RESULTS

There was no significant difference in the 1-year RFS rate in patients treated with Tokyo 172 strain and Connaught strain (72.2% vs. 83.5%, respectively; P = 0.698). There were no significant differences in adverse events between the arms. Severe adverse events (>Grade 3) were seen in 15% of the Connaught strain group while no severe adverse events were observed as a result of Tokyo 172 strain.

CONCLUSION

Our results indicated that low-dose Tokyo 172 strain decreased adverse events although it was not significant, and the RFS difference was not statistically significant between the two arms. Further investigation is warranted.

Immunotherapy of genitourinary malignancies

Most cancer patients are treated with some combination of surgery, radiation, and chemotherapy. Despite recent advances in local therapy with curative intent, chemotherapeutic treatments for metastatic disease often remain unsatisfying due to severe side effects and incomplete long-term remission. Therefore, the evaluation of novel therapeutic options is of great interest. Conventional, along with newer treatment strategies target the immune system that suppresses genitourinary (GU) malignancies. Metastatic renal cell carcinoma and non-muscle-invasive bladder caner represent the most immune-responsive types of all human cancer. This review examines the rationale and emerging evidence supporting the anticancer activity of immunotherapy, against GU malignancies.

Long-term Outcome of a Low-dose Intravesical Bacillus Calmette–Guerin Therapy for Carcinoma In Situ of the Bladder: Results After Six Successive Instillations of 40 mg BCG

BACKGROUND

In Japan, bacillus Calmette-Guerin (BCG: Tokyo 172 strain) instillation is generally performed at a dose of 80 mg once weekly for eight consecutive weeks; however, many adverse effects including severe ones have been reported. We employed a dose of 40 mg once a week for six consecutive weeks in principle for carcinoma in situ (CIS) of the bladder, and retrospectively evaluated its effectiveness and safety.

METHODS

A total of 43 patients with CIS of the bladder were treated by this method and followed-up for a subsequent 12-79 months (median, 54 months). The patients consisted of 35 males and eight females aged 45-87 years (mean, 67.5 years). Intravesical BCG instillation at a dose of 40 mg was conducted once a week for six consecutive weeks.

RESULTS

A complete response (CR) was achieved in 84% of the patients, in whom the recurrence-free rate was 72.4% after 3 years and 61.9% after 5 years. The median CR duration was 37.5 months. Two patients underwent total cystectomy, but none died of bladder cancer. As adverse effects, bladder irritation symptoms were observed in 48.8%, pyuria in 46.5%, macroscopic hematuria in 18.6% and fever (>37.5 degrees C) in 9.3%. There were no severe adverse effects requiring discontinuation of drug administration.

CONCLUSION

Our present study corroborated both the effectiveness and safety of low-dose BCG therapy for CIS of the bladder. This therapy warrants further study by prospective randomized trials in the future.

BACILLUS CALMETTE-GUERIN TOKYO172 SUBSTRAIN FOR SUPERFICIAL BLADDER CANCER: CHARACTERIZATION AND ANTITUMOR EFFECT

PURPOSE

We investigated the preparation of bacillus Calmette-Guerin (BCG) Tokyo172 substrain (Japan BCG Laboratory, Ltd., Tokyo, Japan) on the characteristics of bacilli and antitumor activity in a mouse model in comparison with a preparation of the Connaught substrain (Aventis Pasteur, Ltd., Toronto, Ontario, Canada).

MATERIALS AND METHODS

Lyophilized BCG preparations of Tokyo172 and Connaught for superficial bladder cancer were tested. The number of bacilli and cfu per dose, dispersion, size and attachment to murine bladder tumor cells were determined after reconstitution. Antitumor activity was assessed by intradermal injection of tumor cells with various doses of either BCG preparation into the flanks of syngeneic mice, followed by the observation of tumor suppression and survival in mice.

RESULTS

Each dose of Tokyo172 had about half the bacilli in a dose of Connaught but the cfu content was about 13-fold higher for Tokyo172 than for Connaught. After reconstitution Tokyo172 bacilli were better dispersed with fewer aggregates than Connaught bacilli. Tokyo172 bacilli were about half as long as Connaught bacilli and Tokyo172 bacilli showed better attachment to tumor cells in vitro. In mice Tokyo172 achieved similar tumor suppression at a lower dose than Connaught.

CONCLUSIONS

High viability, good dispersion and efficient binding to tumor cells by BCG bacilli in the Tokyo172 preparation seem to be the main reasons for the lower clinical dose of this preparation compared with the Connaught preparation (18 vs 81 mg dry weight).

Low dose BCG as adjuvant therapy for superficial bladder cancer and literature review

BACKGROUND

Bacillus Calmette-Guerin (BCG) at low doses has long been employed as prophylactic and therapeutic treatment for superficial cancer of the urinary bladder, aiming at reducing toxicity while maintaining efficacy. A retrospective review was reported, together with a review of the literature with respect to a low dose BCG regimen.

METHODS

Forty-five consecutive patients with superficial bladder cancer (Ta or T1) with one or more of the appropriate criteria (grade above 1, stage above a, size >1 cm, multiple or recurrent), after complete transurethral resection, received 27 mg Connaught strain BCG weekly for 6 weeks. There was no maintenance therapy. Patients were evaluated with urine cytology and cystoscopy. Recurrence, progression and death were analysed.

RESULTS

With a median follow up of 14 (range 3-61) months, 24 (53%) of the 45 patients responded to one course of 6 weekly BCG without recurrence. A further group of 13 (29%) patients responded to a second course of BCG on recurrence. Disease progressed in one (2.2%) patient. Two (4.4%) patients died of an unrelated condition. There was no disease specific mortality. Side-effects were common but well tolerated, with only two (4.4%) cases of treatment interruption.

CONCLUSIONS

Low dose BCG could be an alternative option of adjuvant therapy for superficial bladder cancer with acceptable toxicity and good compliance.

Evaluation of multiple recurrence events in superficial bladder cancer patients treated with intravesical bacillus Calmette-Guérin therapy using the Andersen-Gill's model

To evaluate factors affecting recurrence after intravesical bacillus Calmette-Guérin (BCG) therapy (Tokyo 172 strain), we reviewed data for 101 patients with superficial bladder cancer (pTa [n = 80] and pT1 [n = 21]) treated between 1985 and 1999. The median follow-up period was 58.9 months. Factors affecting the first tumour recurrence were evaluated using Cox's proportional hazards model and those affecting multiple recurrence with Andersen-Gill's model. The 5-year recurrence-free rate was 63% for all 101 patients. The recurrence frequency, defined as times per 100 patient-months of follow-up, greatly decreased from 7.3 +/- 9.6 (SD) before the instillation to 2.6 +/- 5.6 after the therapy (p < 0.0001). Patients with pT1 tumours tended to have earlier recurrence than those with pTa tumours (p = 0.06). Multivariate analysis using Cox's proportional hazards model revealed that a history of bladder cancer and pathological stage were independent factors affecting the first tumour recurrence after the BCG therapy. When multiple endpoints of recurrence were evaluated using the Andersen-Gill's model, number of tumours as well as a history of bladder cancer and pathological stage demonstrated significant links to tumour recurrence after the BCG therapy. The 5-year progression-free and 5-year survival rates were 89.3% and 85.3% for all the 101 patients, respectively. Because intravesical recurrence may involve multiple events during the clinical course of patients with bladder cancer, the Andersen-Gill's model appears useful for evaluation of risk factors.

Sufficient prophylactic efficacy with minor adverse effects by intravesical instillation of low-dose bacillus Calmette-Guérin for superficial bladder cancer recurrence

BACKGROUND

Intravesical instillation of bacillus Calmette-Guérin (BCG) is the most efficient strategy for prophylaxis of superficial bladder cancer recurrence. Adverse effects of BCG are major obstacles, but the reduction of BCG dose could minimize these effects. The efficacy and adverse effects of half-dose (40 mg) BCG, Tokyo 172 strain, were prospectively evaluated.

METHODS

A total of 93 patients with superficial bladder cancer (pTa or pT1) were sequentially assigned to receive either 40 or 80 mg of BCG after transurethral resection. BCG was administered weekly for 6 weeks postoperatively. Eighty patients observed longer than 12 months after BCG therapy (41, 40 mg group; 39, 80 mg group) were analyzed.

RESULTS

BCG therapy course was completed in 71 patients. Tumor recurrence was recognized in 11 of 40 patients in the 40 mg group and in 5 of 31 patients in the 80 mg group. There was no significant difference in tumor recurrence rate between the two groups (P = 0.547). BCG therapy was withdrawn in 1 patient in the 40 mg group and in 8 patients in the 80 mg-group because of BCG-related adverse effects. The morbidity of BCG-related toxicity was significantly higher in the 80 mg group.

CONCLUSION

Half-dose of BCG Tokyo 172 strain had a similar efficacy and its toxicity was significantly lower compared to the standard dose. Thus, half-dose of this strain might be suitable, at least for initial BCG therapy, for the prophylaxis of bladder cancer recurrence. Further study would be necessary to clarify the efficacy of low-dose instillation in high-risk patients.

Multivariate evaluation of factors affecting recurrence, progression, and survival in patients with superficial bladder cancer treated with intravesical bacillus Calmette-Guérin (Tokyo 172 strain) therapy: significance of concomitant carcinoma in situ

To evaluate the relative importance of clinicopathological factors affecting recurrence, progression, and survival in patients with superficial bladder cancer (pTa and pT1) undergoing bacillus Calmette-Guerin (BCG) therapy (Tokyo 172 strain), we reviewed data for 146 patients treated between 1985 and 1998. The median follow-up period was 64.7 months. Tumour recurrence, progression, and death were evaluated as endpoints using Cox's proportional hazards model. The 5-year recurrence-free rate was 56% for all 146 patients. Those with a past history of bladder cancer (n = 73) had significantly earlier recurrence than those without (n = 73, p = 0.017) and this tended to be the case for concomitant CIS (n = 34) although this did not reach statistical significance. The 5-year progression rate was 15% for all 146 patients and univariate analysis revealed that the presence of concomitant CIS was significantly associated with disease progression (p = 0.002). Multivariate analysis using the proportional hazards model confirmed the finding that only one factor, concomitant CIS, was significantly associated with progression. The 5-year survival rate was 84% for all 146 patients. Furthermore, univariate and multivariate analyses revealed that patient age, history of bladder cancer, and concomitant CIS were variables significantly related to patient survival. The present findings suggest that careful follow-up is mandatory after BCG instillation therapy for patients with superficial bladder cancer and concomitant CIS because of their relatively poor prognosis.

Long-term follow-up of a randomized prospective trial comparing a standard 81 mg dose of intravesical bacille Calmette-Guérin with a reduced dose of 27 mg in superficial bladder cancer

OBJECTIVES

To determine the efficacy of a three-fold reduced dose (RD, 27 mg) of intravesical bacille Calmette-Guérin (BCG) against the standard dose (81 mg) in patients with superficial bladder cancer, assessing recurrence, progression and differences in toxicity.

PATIENTS AND METHODS

Five hundred patients with superficial bladder cancer (Ta, T1, Tis) were enrolled and randomly assigned to be treated after transurethral resection of all visible lesions with intravesical BCG Connaught strain (weekly x six and thereafter fortnightly x six) either with the standard or RD instillation.

RESULTS

All but one of the 500 patients were evaluable for efficacy and toxicity (252 in the standard arm and 247 in the RD arm). The median follow-up was 69 months (maximum 104); 71 (28%) patients in the standard arm and 76 (31%) in the RD arm developed recurrences; the median time to recurrence has not yet been attained, but at 5 years the mean (sd) percentage of recurrence-free patients was 70.5 (3.12) and 70.4 (3.1) for the standard and RD arms, respectively. In patients presenting with multifocal tumours, the standard dose was more effective against recurrences than the RD (P=0.0151). In those with G3 and high-risk tumours overall, the superiority of the standard dose was marginal (P=0.060 and P=0.082). Twenty-nine (11.5%) tumours in the standard arm and 33 (13.3%) in the RD arm progressed to invasive disease; the median time to progression has not yet been attained, but the percentage of progression-free patients at 5 years was 88.8 (2.23) and 86.9 (2.31) for the standard and RD arms, respectively. The standard dose was more effective than the RD against progression only in patients with multifocal disease (P=0.048). Twelve (4.8%) cystectomies were performed in the standard and 15 (6.1%) in the RD arm. Currently, 106 (21.2%) patients have died, but only 38 (7.6%) from bladder cancer, i.e. 20 (7.9%) in the standard and 18 (7.5%) in RD arm. Overall the disease-specific death rate was lower for those patients who completed the scheduled treatment. The cause-specific survival at 5 years did not differ between the arms (P=0.76) but there was a trend toward better cause-specific survival for patients with multifocal tumours in the standard arm. Toxicity differed between the arms, significantly more patients having no toxicity in the RD arm, and fewer having delayed instillations or withdrawing. However, severe systemic toxicity occurred even in patients treated with the RD, in a similar proportion to those receiving the standard dose.

CONCLUSION

Overall, the RD gave similar results for recurrence and progression but with significantly less toxicity. However, patients with multifocal tumours fared better with the standard dose and there was a trend towards better recurrence rates in patients with high-risk tumours. We recommend continuing to use the standard dose for high-risk tumours, while we consider the reduced dose safe and effective for intermediate-risk lesions and for maintenance schedules.

Current use and questions concerning intravesical bladder cancer group for superficial bladder cancer

Bacille Calmette-Guerin (BCG) is the most effective therapy for CIS of the bladder. Although several series have shown a decrease in recurrence and progression of T1 tumor, this effect is temporary. More than one half of patients with T1 tumors treated with BCG will progress over the longterm. A second course of BCG is indicated after an initial complete response. There is no definitive answer regarding the efficacy of maintenance therapy or the optimum dose of BCG. Randomized trials are needed to address these issues in a more conclusive manner. Phase III trials have shown that mitomycin C can be as effective as BCG in the management of papillary tumors; however, BCG is more effective in patients with CIS and high-risk superficial tumors.

Possible factors affecting response to intravesical bacillus Calmette-Guérin (Tokyo 172 strain) therapy for carcinoma in situ of the bladder: a multivariate analysis

To evaluate clinicopathological factors affecting response to intravesical instillation therapy with the bacillus Calmette-Guérin (BCG) Tokyo 172 strain for carcinoma in situ (CIS) of the bladder, we reviewed data for 84 patients treated between 1985 and 1996. Median follow-up was 56 months. The patients comprised three groups: primary (only the in situ lesion, 31 patients), subsequent (found after treatment of a gross neoplasm, 20), and concomitant (found together with a gross neoplasm, 33). A complete response was found in 62 (74%) of the 84 patients. Intravesical BCG therapy eradicated tumour cells in 74% of the primary group, 70% of the subsequent group, and 76% of the concomitant group. Multivariate logistic regression analysis revealed that the presence of gross haematuria and patient age were significantly associated with a complete response to the intravesical BCG therapy (p<0.05). On the other hand, gender, irritative bladder symptoms, type of extent of CIS, histological grade of CIS, BCG dose, and number of times BCG was given did not exert any significant influence. The 5-year recurrence rate was 33% for the 62 patients for whom a complete response was once achieved. Patients aged 60 or older had a higher probability of recurrence than those less than 60 years of age (p<0.05). Disease progression was found in 13% of the 84 patients and total cystectomy was performed in 19%. The present finding that patient age is related to the response to intravesical BCG therapy may point to a role for the reduced host immunocompetence in elderly individuals.

The association between CD2+ peripheral blood lymphocyte subsets and the relapse of bladder cancer in prophylactically BCG-treated patients

We investigated the potential existence of differences in the distribution of T-lymphocyte subsets and in the proliferative response of these CD2+ cells to polyclonal mitogens in patients with transitional cell bladder carcinoma (SBTCC) treated with prophylactic intracavitary instillations of bacillus Calmette-Guerin (BCG) according to their clinical response to this treatment. Before BCG treatment, different subset distribution (CD8+ and CD3+ CD56+), activation antigen expression (CD3+ HLA- DR+) and proliferative response to mitogenic signals were found in CD2+ cells from SBTCC patients prophylactically treated with BCG who remained free of disease or those who had recurrence of tumour. Otherwise, the prophylactic intracavitary BCG instillations in SBTCC patients are associated with a transitory variation of T-lymphocyte subset distribution (CD4 and CD8) and activation antigens expression (CD25).

Intravesical bacillus Calmette-Guérin (Tokyo 172 strain) therapy for carcinoma in situ of the bladder

To evaluate the clinical response to intravesical instillation therapy with bacillus Calmette-Guérin (BCG) Tokyo 172 strain for carcinoma in situ (CIS) of the bladder and subsequent patient prognosis, we reviewed data for 30 patients treated between 1985 and 1994. Median follow-up was 56 months. The CIS cases comprised two groups: primary (19 patients) and subsequent to development of a gross neoplasm (11 patients). Either 40 mg (n = 20) or 80 mg (n = 10) doses of BCG were instilled weekly for 8 weeks. This intravesical therapy resulted in apparent eradication of tumour cells in 25 of the 30 patients for a complete response (CR) rate of 83%, with no difference found between primary and secondary groups. Tumours later recurred in 6 of the 25 patients (24%) and disease progression was found in only 3 (12%). In contrast, progression occurred in 3 of 5 patients (60%) for which a complete response was not achieved with intravesical BCG therapy. The difference between these two groups was significant (p = 0.04). Total cystectomy was performed in 2 of 25 CR patients (8%) first and in 4 of the 5 unresponsive (80%), the statistical difference being highly significant (p = 0.003). The 5-year survival rate was 96% for the study subjects as a whole. In conclusion, CIS unresponsive to BCG therapy should be treated with immediate total cystectomy while cases demonstrating a complete response should be followed up for a long period.