Long-term results and complications of intracavitary bacillus Calmette-Guerin therapy for bladder cancer

Harnessing innate immune pathways for therapeutic advancement in cancer

The innate immune pathway is receiving increasing attention in cancer therapy. This pathway is ubiquitous across various cell types, not only in innate immune cells but also in adaptive immune cells, tumor cells, and stromal cells. Agonists targeting the innate immune pathway have shown profound changes in the tumor microenvironment (TME) and improved tumor prognosis in preclinical studies. However, to date, the clinical success of drugs targeting the innate immune pathway remains limited. Interestingly, recent studies have shown that activation of the innate immune pathway can paradoxically promote tumor progression. The uncertainty surrounding the therapeutic effectiveness of targeted drugs for the innate immune pathway is a critical issue that needs immediate investigation. In this review, we observe that the role of the innate immune pathway demonstrates heterogeneity, linked to the tumor development stage, pathway status, and specific cell types. We propose that within the TME, the innate immune pathway exhibits multidimensional diversity. This diversity is fundamentally rooted in cellular heterogeneity and is manifested as a variety of signaling networks. The pro-tumor effect of innate immune pathway activation essentially reflects the suppression of classical pathways and the activation of potential pro-tumor alternative pathways. Refining our understanding of the tumor's innate immune pathway network and employing appropriate targeting strategies can enhance our ability to harness the anti-tumor potential of the innate immune pathway and ultimately bridge the gap from preclinical to clinical application.

Harnessing the innate immune system by revolutionizing macrophage-mediated cancer immunotherapy

Immunotherapy is a promising and safer alternative to conventional cancer therapies. It involves adaptive T-cell therapy, cancer vaccines, monoclonal antibodies, immune checkpoint blockade (ICB), and chimeric antigen receptor (CAR) based therapies. However, most of these modalities encounter restrictions in solid tumours owing to a dense, highly hypoxic and immune-suppressive microenvironment as well as the heterogeneity of tumour antigens. The elevated intra-tumoural pressure and mutational rates within fastgrowing solid tumours present challenges in efficient drug targeting and delivery. The tumour microenvironment is a dynamic niche infiltrated by a variety of immune cells, most of which are macrophages. Since they form a part of the innate immune system, targeting macrophages has become a plausible immunotherapeutic approach. In this review, we discuss several versatile approaches (both at pre-clinical and clinical stages) such as the direct killing of tumour-associated macrophages, reprogramming pro-tumour macrophages to anti-tumour phenotypes, inhibition of macrophage recruitment into the tumour microenvironment, novel CAR macrophages, and genetically engineered macrophages that have been devised thus far. These strategies comprise a strong and adaptable macrophage-toolkit in the ongoing fight against cancer and by understanding their significance, we may unlock the full potential of these immune cells in cancer therapy.

Targeting Innate Immunity in Cancer Therapy

The majority of current cancer immunotherapy strategies target and potentiate antitumor adaptive immune responses. Unfortunately, the efficacy of these treatments has been limited to a fraction of patients within a subset of tumor types, with an aggregate response rate of approximately 20% to date across all malignancies. The success of therapeutic inhibition of programmed death protein 1 (PD-1), protein death ligand 1 (PD-L1) and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) with immune checkpoint inhibitors (ICI) has been limited to “hot” tumors characterized by preexisting T cell infiltration, whereas “cold” tumors, which lack T cell infiltration, have not achieved durable benefit. There are several mechanisms by which “cold” tumors fail to generate spontaneous immune infiltration, which converge upon the generation of an immunosuppressive tumor microenvironment (TME). The role of the innate immune system in tumor immunosurveillance and generation of antitumor immune responses has been long recognized. In recent years, novel strategies to target innate immunity in cancer therapy have emerged, including therapeutic stimulation of pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs); the DNA sensing cGAS/STING pathway; nucleotide-binding oligomerization domain-like receptors (NLRs), such as NLRP3; and the retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs). In addition, therapeutic modulation of key innate immune cell types, such as macrophages and natural killer cells, has been investigated. Herein, we review therapeutic approaches to activate innate immunity within the TME to enhance antitumor immune responses, with the goal of disease eradication in “cold” tumors. In addition, we discuss rational immune-oncology combination strategies that activate both innate and adaptive immunity, with the potential to enhance the efficacy of current immunotherapeutic approaches.

Rapid detection of bacille Calmette-Guérin-associated mycotic aortic aneurysm using novel cell-free DNA assay

Intravesical instillation of bacille Calmette-Guérin (BCG), an attenuated strain of Mycobacterium bovis, is an adjuvant immunotherapy for bladder carcinoma. Typical complications include fever, malaise, and dysuria. However, more severe complications have been reported, including granulomatous pneumonitis, BCG sepsis, and vascular infections. We present a case of an infrarenal abdominal aortic aneurysm complicated by iliopsoas abscess 2 years after BCG treatment and discuss a novel diagnostic tool for mycobacterial strain identification.

Phase II trial of intravesical nanoparticle albumin bound paclitaxel for the treatment of nonmuscle invasive urothelial carcinoma of the bladder after bacillus Calmette-Guérin treatment failure

PURPOSE

Response rates to current second line intravesical therapies for recurrent nonmuscle invasive bladder cancer range between 10% and 30%. Nanoparticle albumin bound (nab-)paclitaxel has increased solubility and lower toxicity compared to other taxanes. Results of the phase I intravesical trial of this compound demonstrated minimal toxicity during dose escalation. We now report the results of a phase II trial to assess efficacy.

MATERIALS AND METHODS

This study was an investigator initiated, single center, single arm, phase II trial investigating the use of nab-paclitaxel in patients with recurrent Tis, T1 and Ta urothelial carcinoma in whom at least 1 prior regimen of intravesical bacillus Calmette-Guérin failed. Patients received 500 mg/100 ml nab-paclitaxel administered in 6 weekly intravesical instillations. Efficacy was evaluated with cystoscopy, biopsy, cytology and imaging. If complete response was achieved, patients were treated with full dose monthly maintenance treatments for 6 months.

RESULTS

A total of 28 patients were enrolled in the study. Of these patients 10 (35.7%) exhibited a complete response after initial treatment. At 1 year all of these responses remained durable after maintenance therapy. At a mean followup of 21 months (range 5 to 47) 19 of 28 (67.8%) patients retained their bladders without progression or distant metastases. A single patient had progression to muscle invasive disease at radical cystectomy. Treatment related adverse events were noted in 9 of 28 (32.1%) patients and were limited to grade 1 or 2.

CONCLUSIONS

Intravesical nab-paclitaxel has minimal toxicity and a 35.7% response rate in patients with nonmuscle invasive bladder cancer and previous bacillus Calmette-Guérin failure. Complete response remained durable at 1 year followup in this heavily pretreated patient population.

Expert review: an update in current and developing intravesical therapies for non-muscle-invasive bladder cancer

Non-muscle-invasive bladder cancer is a highly prevalent disease and recurrences, after initial therapy, are common. Consequently, the healthcare costs for non-muscle-invasive bladder cancer are high. Despite a primary adequate response to adjuvant intravesical treatment, many patients suffer from recurrences, and some even from progression. To date, cystectomy remains the only option for those non-responding patients with high risk of recurrence and progression. Mainly because outcome after progression, in this group, is poor. Therefore, new intravesical therapies are needed. Moreover, new accurate and individual parameters, to distinguish responder from non-responders, will provide additional benefit in clinical decision-making. In this review, current diagnostics and therapies will be discussed. In addition, we will elucidate developing therapies in non-muscle-invasive bladder cancer.

Experience with newer intravesical chemotherapy for high-risk non-muscle-invasive bladder cancer

The definitive treatment for patients with high-risk non-muscle-invasive bladder cancer (NMIBC) who fail to respond to intravesical bacillus Calmette-Guérin (BCG) is cystectomy. However, many patients who experience recurrence after BCG are either poor operative candidates or refuse surgery due to the long-term impact on their quality of life. In the last decade, there has been an increased interest in alternative intravesical therapies, and several novel chemotherapeutics have emerged as promising agents for high-risk NMIBC patients unable or unwilling to undergo cystectomy. Additionally, extended treatment regimens with combined induction and maintenance therapy have been investigated, and may increase the durability of response to these new agents, as has been shown for conventional intravesical therapy.

Interferon alfa in the treatment paradigm for non-muscle-invasive bladder cancer

OBJECTIVES

In this article, we review the various options for and the potential role of interferon alfa (IFN-α) in the treatment of non-muscle-invasive bladder cancer (NMIBC).

METHODS

PubMed was searched for journal articles on IFN-α use in treating bladder cancer. The references listed in the National Comprehensive Cancer Network guidelines were used as a guide to identify relevant publications on treatments for NMIBC.

RESULTS

Transurethral resection with adjuvant intravesical chemotherapy or immunotherapy is the standard treatment option for NMIBC. Adjuvant IFN-α therapy has limited efficacy in preventing recurrences in intermediate-risk and high-risk patients; bacillus Calmette-Guérin (BCG) monotherapy is the recommended first-line treatment in these patients. Unfortunately, cancer progression or recurrence is a common outcome; radical cystectomy, which is often the lifesaving approach in such a scenario, is associated with significant morbidity, mortality, and decreased quality of life. Current alternatives to cystectomy include repeat intravesical immunotherapy, conventional instillation chemotherapy, and device-assisted intravesical chemotherapy. The efficacy of any chemotherapy after BCG failure, either conventional or device assisted, has not been established. BCG and IFN-α combination intravesical therapy has not been investigated thoroughly; based on available data, combination therapy appears to be most effective in patients with carcinoma in situ and may be preferentially considered as an alternative to radical cystectomy for patients with intermediate-risk or high-risk NMIBC who do not tolerate the standard BCG dose or experience BCG failure after 1 year of therapy. However, this approach requires close follow-up and should only be chosen after careful consideration of all risk factors.

CONCLUSIONS

There is a lack of efficacious treatment options for patients with NMIBC recurrence or progression after initial BCG treatment. There is a need for well-designed clinical trials investigating the safety and efficacy of available therapies, including BCG and IFN-α2b combination therapy.

A phase I trial of intravesical nanoparticle albumin-bound paclitaxel in the treatment of bacillus Calmette-Guérin refractory nonmuscle invasive bladder cancer

PURPOSE

Up to 50% of patients treated with intravesical agents for high grade nonmuscle invasive bladder cancer will have disease recurrence. Response rates to current second line intravesical therapies are low and for these high risk patients novel agents are necessary. Our previously completed phase I trial showed docetaxel was a safe agent for intravesical use. Nanoparticle albumin-bound paclitaxel (Abraxane®, ABI-007) has been shown to have increased solubility and lower toxicity compared to docetaxel in systemic therapy. Thus, we assessed the dose limiting toxicity and maximum deliverable dose of intravesical nanoparticle albumin-bound paclitaxel.

MATERIALS AND METHODS

Inclusion criteria for this institutional review board approved phase I trial were recurrent high grade Ta, T1 and Tis transitional cell carcinoma of the bladder for which at least 1 prior standard intravesical regimen failed. Six weekly instillations of nanoparticle albumin-bound paclitaxel were administered with a modified Fibonacci dose escalation model used until the maximum deliverable dose was achieved. The primary end point was dose limiting toxicity and the secondary end point was response rate.

RESULTS

A total of 18 patients were enrolled in the study. One patient demonstrated measurable systemic absorption after 1 infusion. Grade 1 local toxicities were experienced by 10 (56%) patients with dysuria being the most common, and no grade 2, 3 or 4 drug related local toxicities were encountered. Of the 18 patients 5 (28%) had no evidence of disease at posttreatment evaluation.

CONCLUSIONS

Intravesical nanoparticle albumin-bound paclitaxel exhibited minimal toxicity and systemic absorption in the first human intravesical phase I trial to our knowledge. A larger phase II study has begun to formally evaluate the activity of this regimen.

Novel intravesical therapies for non-muscle-invasive bladder cancer refractory to BCG

The definitive treatment for patients with non-muscle-invasive bladder cancer (NMIBC) who fail to respond to intravesical BCG is cystectomy. When a patient is deemed BCG-refractory and cannot or will not undergo cystectomy, alternative intravesical therapy may be the most effective way to minimize recurrence and progression. A number of immunotherapeutic and chemotherapeutic agents have been given intravesically over the years, and several recently and currently investigated novel agents appear to be particularly promising for the management of BCG-refractory NMIBC. The most effective treatments in the future will likely utilize targeted therapies based on the underlying genetic mutations associated with each individual diagnosis of NMIBC.

Long-term clinical outcomes of a phase I trial of intravesical docetaxel in the management of non-muscle-invasive bladder cancer refractory to standard intravesical therapy

OBJECTIVES

To report the long-term clinical outcomes and durability of response after treatment with induction intravesical docetaxel. Most novel agents used to treat bacillus Calmette-Guerin refractory high-grade non-muscle-invasive (NMI) bladder cancer are evaluated only after short follow-up periods. Our previously published phase I trial demonstrated that docetaxel is a safe agent for intravesical therapy with minimal toxicity and no detectable systemic absorption. We sought to determine long-term clinical outcomes after treatment with intravesical docetaxel.

METHODS

Eighteen patients with recurrent Ta (n = 7), T1 (n = 5), and Tis (n = 6) transitional cell carcinoma who experienced treatment failure with at least 1 prior intravesical therapy completed the phase I trial. Docetaxel was administered as 6 weekly intravesical instillations using a dose-escalation model terminated at 0.75 mg/mL. Efficacy was evaluated by interval cystoscopy with biopsies when indicated, cytology, and computed tomography imaging. Follow-up consisted of quarterly cystoscopy, cytology, computed tomography, and biopsy when indicated.

RESULTS

With a median follow-up of 48.3 months, 4 patients (22%) have demonstrated a complete durable response and currently remain disease-free without further treatment. Three patients (17%) had a partial response, defined as a single NMI recurrence with no further therapy for bladder cancer. Eleven patients (61%) failed treatment, and required another intervention. One patient developed stage progression. No delayed toxicities were noted. The median disease-free survival time was 13.3 months.

CONCLUSIONS

After 4 years of follow-up without maintenance therapy, intravesical docetaxel has demonstrated the ability to prevent recurrence in a select number of patients with refractory NMI bladder cancer and warrants further investigation.

Henoch-Schönlein purpura after intravesical administration of bacillus Calmette-Guérin

The administration of intravesical bacille Calmette-Guérin (BCG) in early stages of bladder cancer is usually a safe therapy. Side-effects of BCG immunotherapy can be of both local and systemic nature. We report the first case of Henoch-Schönlein purpura following intravesical administration of BCG.

Additional evidence that pityriasis rosea is associated with reactivation of human herpesvirus-6 and -7

To elucidate the role of human herpesvirus (HHV)-6 and -7 (HHV-7) in pityriasis rosea (PR), we measured their DNA load in plasma, peripheral blood mononuclear cells (PBMC), and tissues using a calibrated quantitative real-time PCR assay. We also studied HHV-6- and HHV-7-specific antigens in skin by immunohistochemistry and anti-HHV-7 neutralizing activity using a syncytia-inhibition test. Plasma and PBMC were obtained from 31 PR patients (14 children, 17 adults), 12 patients with other dermatites, and 36 blood donors. Skin biopsies were obtained from 15 adults with PR and 12 with other dermatites. HHV-6 and HHV-7 DNA were detected in 17% and in 39% of PR plasmas, respectively, but in no controls. HHV-7 viremia was associated with a higher PBMC load and, in adults, with systemic symptoms. HHV-7, but not HHV-6, levels in PBMC were higher in PR patients than in controls. HHV-6 and HHV-7 antigens were found only in PR skin (17% and 67% of patients analyzed, respectively), indicating a productive infection. Syncytia-neutralizing antibodies were found in PR patients and controls, but their titers were lower in patients with HHV-7 viremia. These data confirm the causal association between PR and active HHV-7 or, to a lesser extent, HHV-6 infection.

Vesicoureteral reflux after intravesical instillation of bacillus Calmette-Guérin against carcinoma in situ of the bladder

We report a case of vesicoureteral reflux (VUR) 3 years after intravesical instillation of bacillus Calmette-Guérin (BCG, Tokyo 172 strain) against carcinoma in situ of the bladder. The present case suggests that a long-term careful follow-up is needed to detect not only tumor recurrences but also VUR as a late complication after intravesical BCG instillation.

[Classification, favorable characteristics, prevention and treatment of adverse side-effects associated with Bacillus Calmette-Guerin in the treatment of superficial bladder cancer]

The efficacy of Bacillus Calmette-Guérin (BCG) in the treatment of superficial bladder cancer was first reported by Morales in 1976. Several authors have since demonstrated the efficacy of BCG in the prophylaxis and treatment of high-risk superficial bladder tumors (pT1G3, CIS). Although BCG is now recommended as an adjunctive treatment for superficial bladder tumors, the optimal treatment schedule remains to be defined. Results reported by Lamm suggest that an initial induction cycle of six weekly intravesical BCG instillations is suboptimal unless maintenance therapy (three consecutive weekly instillations) is given 3, 6, 12, 18, 24, 30 and 36 months later. However, the use of maintenance therapy is hindered by troublesome adverse reactions. This article reviews adverse reactions associated with BCG treatment, proposed a classification and discusses their prevention and treatment.

Long-term maintenance bacille Calmette-Guérin therapy in high-grade superficial bladder cancer

OBJECTIVES

To assess the long-term results of intravesical bacille Calmette-Guérin (BCG) induction plus long-term maintenance treatment for high-grade superficial bladder cancer.

METHODS

Between 1994 and 2000, 41 patients who presented to our clinic with superficial urothelial carcinoma of the bladder (T1G3, T1G3 plus carcinoma in situ, or recurrent TaG2-3) were treated by transurethral resection of all visible tumor and an induction cycle of BCG plus a long-term maintenance BCG course consisting of 11 monthly instillations followed by 4 quarterly instillations and then by 6 six-monthly instillations. The median follow-up was 40 months.

RESULTS

Thirty patients remained tumor free throughout the follow-up period. Ten patients had a recurrence of superficial tumor, 9 patients during the monthly instillation course and 1 patient during the quarterly instillation course. One patient presented with progression.

CONCLUSIONS

Adjuvant immunotherapy with BCG after complete transurethral resection of bladder tumor represents a highly effective primary treatment for high-grade superficial bladder cancer. Our maintenance course of BCG seemed to improve the worldwide accepted effectiveness of the BCG induction course without any important side effects.

Effects of tumor necrosis factor-alpha and interferon-gamma on expressions of matrix metalloproteinase-2 and -9 in human bladder cancer cells

We have investigated the effects of tumor necrosis factor-alpha (TNF-alpha) and interferon (INF-gamma), the potent Bacillus Calmette-Guerin (BCG)-induced cytokines on the production of MMP-2, MMP-9, TIMP-1, TIMP-2 and MT1-MMP in high grade human bladder cancer cell lines, T-24, J-82 and HT-1376 cell lines. MMP-2 expression and activity were decreased in T-24 cells treated with both cytokines in a dose dependent manner. However, J-82 cells treated with TNF-alpha and INF-gamma revealed dose dependent increases of MMP-9 expression and activity with similar baseline expression and activity of MMP-2. HT-1376 cells after exposure to TNF-alpha only enhanced the expression and activity of MMP-9. These results indicate that TNF-alpha and INF-gamma could regulate the production of MMP-2 or MMP-9 on bladder cancer cells and their patterns of regulation are cell specific. Furthermore, this diverse response of bladder cancer cells to TNF-alpha and INF-gamma suggests that BCG immunotherapy may enhance the invasiveness of bladder cancer in certain conditions with induction of MMPs.

[Indications for BCG in surface tumors of the bladder]

Overall view of Bacille de Calmette-Guerin (BCG) immunotherapy in the prophylaxis and treatment of surface cancer of the bladder. A series of issues, on some of which a consensus has been reached while controversy is still frequent in others are discussed. Intravesical instillation of BCG as the single route has been considered to best mode of administration. With regard to the BCG strain to be used, there is still no consensus after the analysis of the data provided by the studies conducted. Relative to the treatment schedule, it appears clear that maintenance therapy is superior to an exclusively induction regime. No consensus has been reached about optimal dosage or the possibility to reduce toxicity. Although some studies support the belief that intravesical immunotherapy with BCG is superior to chemotherapy, further data is required to confirm such assumption. In conclusion, although treatment with BCG has proven to be effective in patients with surface tumours of the bladder, it should not be considered a panacea to be indiscriminately used in any patient with this malignancy.

Granulomatous hepatitis following intravesical bacillus Calmette-Guerin therapy

Although intravesical bacillus Calmette-Guerin (BCG) administration is an effective method in the treatment of superficial urinary bladder carcinoma, some complications may arise such as a granulomatous reaction either in the urinary tract or, in rare cases, outside the urinary tract. We report in this paper a case of granulomatous hepatitis following intravesical BCG administration.

Diffuse alveolar damage in BCGosis: a rare complication of intravesical bacillus Calmette-Guérin therapy for transitional cell carcinoma

Intravesical administration of bacillus Calmette-Guérin is a relatively simple procedure used in the treatment of superficial transitional cell carcinoma of the urinary bladder. It is usually well tolerated with few major side effects. In rare instances, systemic complications can result in death. The usual autopsy finding is that of caseating and non-caseating granulomata in the affected organ. We report the second case of BCGosis in which granulomata together with acute and organising phase diffuse alveolar damage were found in the lungs.

Mycobacterium phlei cell wall complex directly induces apoptosis in human bladder cancer cells

Intact mycobacteria and mycobacterial cell wall extracts have been shown to inhibit the growth of human and murine bladder cancer. Their mechanism of action is, however, poorly understood. Mycobacterium phlei mycobacterial cell complex (MCC) is a cell wall preparation that has mycobacterial DNA in the form of short oligonucleotides complexed on the cell wall surface. In this study, we have investigated the possibility that MCC has anti-cancer activity that is mediated by two different mechanisms--a direct effect on cancer cell proliferation and viability and an indirect effect mediated by the production of interleukin 12 (IL-12), a cytokine known to possess anti-cancer activity. We have found that, although MCC is a potent inducer of IL-12 and IL-6 synthesis in monocytes and macrophages either in vitro or in vivo, it is unable to induce the synthesis of either IL-12, IL-6 or granulocyte-macrophage colony-stimulating factor (GM-CSF) by the human transitional bladder cancer cell lines HT-1197 and HT-1376. MCC is not directly cytotoxic towards these cancer cells, but induces apoptosis as determined by nuclear DNA fragmentation and by the release of nuclear mitotic apparatus protein. Mycobacterium phlei DNA associated with MCC is responsible for the induction of apoptosis. Our results indicate that MCC directly effects bladder cancer cells by inhibiting cellular proliferation through the induction of apoptosis, and has the potential for an indirect anti-cancer activity by stimulating cancer-infiltrating monocytes/macrophages to synthesize IL-12.

Lack of an antitumoral effect of immunomodulatory galactoside-specific mistletoe lectin on N-methyl-N-nitrosourea-induced urinary bladder carcinogenesis in rats

The aim of the present animal experiment was to study the effect of galactoside-specific lectin or agglutinin (VAA) from mistletoe (Viscum album L.) on chemically induced tumor development in the urinary bladder of rats. Since VAA has been shown to exert a remarkable immunomodulating effect, any change in tumor formation would indicate a lectin-triggered immune control of urothelial carcinogenesis in the used model. To produce vesical neoplasms the direct-acting urothelial carcinogen N-methyl-N-nitrosourea (MNU) was administered at a single intravesical dose (7.5 mg/kg body weight). Highly purified VAA was given subcutaneously twice a week at the immunomodulatory dose of 1 ng/kg body weight over a period of 6 months during the critical phases of tumor development. After a total experimental time of 15 months the incidence of epithelial bladder tumors was 29.3% in controls versus 27.9% in rats additionally receiving the lectin and thus not significantly different in both experimental groups. There were, moreover, no substantial differences in the histopathologic spectrum of epithelial tumors induced, their patterns of growth, grades of cellular malignancy and local extension. The frequency and histopathology of mesenchymal bladder tumors as well as the incidence and morphology of carcinomas of the ureters and renal pelves also proved to be similar in controls and in rats treated with VAA. In conclusion, the present data provide no evidence for a modifying or even inhibitory effect of the immunomodulatory galactoside-specific mistletoe lectin on experimental urothelial carcinogenesis.

Immunostimulating agents: what next? A review of their present and potential medical applications

Many chemical entities, either from natural sources or prepared by synthesis, are known to exert stimulating activities on various functions of the immune system, such as antibody production, resistance to infections, rejection of malignant cells, etc. In this review, the origin, chemical structures and main activities of several immunostimulants are described, with special emphasis on their present or potential medical usefulness. An attempt is made to envisage the future of this type of pharmacological agents, excluding however from the presentation the endogenous modulators of the immune system (cytokines), the production and activities of which are influenced by the immunostimulants themselves.

Mycobacterium cell wall: an alternative to intravesical bacillus Calmette Guerin (BCG) therapy in orthotopic murine bladder cancer

PURPOSE

The antitumor effect of intravesical mycobacterium cell wall (MCW) therapy on orthotopic and heterotopic bladder tumors in the mouse was assessed with magnetic resonance imaging (MRI).

MATERIALS AND METHODS

The live bacillus Calmette Guerin (BCG) organism was replaced with a cell wall extract derived from the outer capsule of Mycobacterium phlei. This alternative form of intravesical therapy was used with the aim of reducing the toxicity associated with the live mycobacterium organism without compromising efficacy. Response to multiple doses of intravesical MCW and BCG was assessed in mice with established MBT-2 tumors after transurethral tumor implantation.

RESULTS

Serial MRI of BCG-treated mice revealed significant tumor regression. The MR images correlated well with the corresponding histology of the whole mount bladder sections. Treatment with MCW also resulted in significant inhibition of tumor growth compared with control untreated animals (p < 0.05) although the antitumor effect was less pronounced than that of live BCG. Treatment was well tolerated in the MCW group with no apparent ill effects. Flow cytometric (FCM) analysis of bladder washings with phenotype-specific monoclonal antibodies revealed predominantly a CD3+ T cell infiltrate in the control and BCG-treated as well as the MCW-treated mice. The CD4+ (helper/inducer) subset of T cells predominated over the CD8+ (suppressor/cytotoxic) subset in both the BCG- and MCW-treated animals, and the CD4+/CD8+ ratio in both of the treated groups differed significantly from that of the control untreated groups.

CONCLUSION

Intravesical MCW appears to invoke a similar inflammatory response in the mouse bladder mucosa as the live BCG organism and retains an antitumor action. It deserves further evaluation as a potential antitumor agent against bladder cancer. A Phase II clinical trial is now underway.

Comparison between bacillus Calmette-Guérin and the A60 mycobacterial antigen complex used as cancer-preventive immunotherapies

Preparations of liver or lysates of Mycobacterium bovis strain Calmette-Guérin (BCG) have long been used as treatments for a variety of cancer types, especially those involving the urinary tract, with varying success. This study was conducted to compare the antitumoral activity of BCG and the thermostable macromolecular antigen complex of BCG (A60) when used as preventive treatments, in conjunction with or without tumor antigens, against growth and dissemination of the EMT6 murine tumor cell line. It was demonstrated that tumor antigens alone did not significantly alter the oncological indexes, although a slight increase in both T lymphocyte and macrophage activations was found. It was further demonstrated that A60 induces a protective activity up to 40% greater than that of live BCG and that this protection was not accompanied by any of the adverse effects sometimes observed during BCG immunotherapy.

BCG versus epirubicin in the prophylaxis of multiple superficial bladder tumours: results of a prospective randomized study using modified treatment schemes

A prospective randomized trial on 94 eligible patients evaluated and compared the efficacy of adjuvant intravesical epirubicin and bacillus Calmette-Guérin (BCG) after complete resection of multifocal superficial bladder cancer. BCG treatment schedule consisted of an induction 6-week course of instillations (150 mg Pasteur BCG per instillation) and single maintenance doses to patients who remained free of recurrences at follow-up examinations for a total treatment period of 2 years. These initial responders received additionally a separate 4-week course of therapy 6 months after the start of treatment. Chemoprophylaxis included an early (on the second postoperative day) instillation followed by 4 weekly treatments with epirubicin (50 mg per instillation) and then by 10 monthly treatments for the initial responders during the first year of follow-up and at every follow-up examination for a total treatment period of 2 years. The overall treatment results did not differ significantly between the 2 arms (54% of patients of the epirubicin group remained free of recurrences compared to 65% of those treated with BCG) for an identical mean follow-up of 35.1 months. However, a significant benefit in favour of BCG when compared with epirubicin was shown in patients who had stage T1 and grade 3 tumours and in terms of relative risk of recurrences, disease-free interval and recurrence rate per 100 patient-months. Both drugs were proved to be safe with manageable toxicity.

Definitive tumor resection and percutaneous bacille Calmette-Guérin for management of renal pelvic transitional cell carcinoma in solitary kidneys

OBJECTIVES

This study was done to evaluate the safety and initial efficacy of definitive tumor resection combined with percutaneous bacille Calmette-Guérin (BCG) for management of renal pelvic transitional cell carcinoma (TCC) in patients with solitary kidneys.

METHODS

Eight patients with anatomically solitary kidneys, all of whom had a prior history of TCC elsewhere in the urinary tract, were treated with either partial nephrectomy (n = 2) or percutaneous resection (n = 6) combined with a 6-week course of topical BCG administered percutaneously. Seven (87.5%) of the 8 patients tolerated the complete BCG course without adverse effects. One patient required cessation of treatment for renal insufficiency, which resolved with discontinuation of therapy. Follow-up nephroscopy was performed 3 months after the initial tumor resection in 6 of the 8 patients, and all patients underwent regular follow-up surveillance at 3- to 6-month intervals thereafter with radiographic, cytologic, and, in some cases, ureteroscopic examinations.

RESULTS

With follow-up ranging from 9 to 59 (mean, 22) months, local tumor recurrence has become evident in only 1 patient. Two other patients have developed distant metastatic disease, both of whom had invasive TCC elsewhere in the urinary tract prior to treatment of the upper tract tumor.

CONCLUSIONS

Combining a 6-week course of percutaneously administered topical BCG with definitive tumor resection is generally well tolerated, and, ultimately, this protocol may result in a decreased incidence of local tumor recurrence in these high-risk patients.

Adenoviral-mediated gene transfer to bladder in vivo

This study was designed to examine the potential for gene therapy in bladder in vivo using adenoviral vectors. Gene transfer to rat bladders was accomplished via direct intravesical instillation using a replication-defective adenoviral vector containing a marker gene encoding for Escherichia coli beta-galactosidase (beta-gal). Successful gene transfer was confirmed by analyzing bladder samples for DNA and RNA using polymerase chain reaction (PCR) with primers specific for beta-gal and adeno sequences, detecting beta-gal in full-thickness bladder wall using specific histochemical staining (X-gal) and documenting recombinant protein production. Bladder architecture was preserved, without evidence of distant spread of virus as assessed by PCR. Gene expression was evident for at least 7 days. In summary, bladder cells can be genetically altered using replication-deficient adenoviral vectors via simple intravesical instillation of vector. Introduction of exogenous genetic material is a potentially powerful therapeutic modality for immunomodulation of bladder neoplasms.

Durability of the tumor-free response for intravesical bacillus Calmette-Guerin therapy

The long-term efficacy of bacillus Calmette-Guerin (BCG) has not been established. We describe the tumor-free status of patients 11 years after BCG treatment. Long-term followup for the patient population (mean 74.3 +/- 3.5 months, range 6 to 129) yielded a 28% (29 of 104 patients) tumor-free status for a single 6-week course of BCG. Of 66 patients who received a second 6-week course of BCG for recurrent tumors after failing the initial 6-week course 27 (41%) have remained tumor-free. Overall, 56 of 104 patients (54%) remain tumor-free after 1 or 2 courses of BCG. Analysis of recurrences with respect to 3 intervals (2 or less, 2 to 5 and more than 5 years) revealed recurrence rates of 61% (63 of 104 patients), 23% (7 of 30) and 22% (5 of 23), respectively, after 1, 6-week course of BCG. Similarly, recurrence rates for the same periods for patients receiving a second 6-week course of BCG were 42% (28 of 66), 21% (6 of 28) and 23% (5 of 22), respectively. Patients receiving either 1 or 2, 6-week BCG courses who were tumor-free at 2 years experienced essentially identical recurrence rates during the 2 to 11-year followup (36% and 33%, respectively). Overall, 23 of 66 patients (35%) who were tumor-free at 2 years had recurrent tumors during the 2 to 11-year followup. We conclude that while BCG is effective therapy for superficial bladder tumors, a continuous potential for tumor recurrence exists for responding patients necessitating life-long followup.

Systemic hypersensitivity reaction to intravesical BCG

BCGosis is a recognised complication of intravesical BCG immunotherapy for superficial bladder carcinoma. We present here a case of granulomatous hepatitis, pneumonitis and probable pericarditis resulting from an hypersensitivity reaction to intravesical BCG.

Intravesical Bacillus Calmette-Guérin with the Danish strain for treatment of carcinoma in situ of the bladder

We report our experience of the treatment of carcinoma in situ (CIS) using intravesical therapy with the Danish Bacillus Calmette-Guérin (BCG) strain 331 (SSI). Forty-two patients received treatment, 11 had primary and 31 secondary CIS. The median follow-up period was 26 months (range 3-68). Patients received 6 weekly instillations (1 course) and non-responders an additional 6 instillations at 2-week intervals (2 courses). The complete response rate was 59% for 1-course patients, 33% for the 2-course patients and 68% for the entire series. Patients were considered treatment failures if they suffered progression to invasive cancer, metastasis or died from transitional cell carcinoma. BCG treatment was more effective in primary than in secondary CIS, with a complete response rate of 80% versus 65% and with no failures versus 35%. Patients with persistent CIS after the first course of BCG had a greater risk of failure than responders: 50% versus 17%. Patients with persistent CIS after the second course had a 75% failure rate. This suggests that cystectomy should be considered for non-responders following a 6-week course and recommended to those not responding to 2 courses. Ten patients had CIS in the prostatic urethra. All responded to BCG treatment; 2 suffered from recurrent CIS 1 associated with invasive urethral tumour. The incidence and severity of side effects were similar to those reported with other strains of BCG. One patient with primary CIS failed to complete the treatment owing to "BCG-itis".

Intravesical 4'-epi-doxorubicin (epirubicin) versus bacillus Calmette-Guérin. A controlled prospective study on the prophylaxis of superficial bladder cancer

BACKGROUND

The selection of the most appropriate antineoplastic agent and optimal treatment schedule for the prophylaxis of superficial bladder cancer against tumor recurrences is the subject of continual investigations.

METHODS

A controlled prospective trial involving 161 patients evaluated and compared the efficacy of intravesical epirubicin and bacillus Calmette-Guérin (BCG) administration as prophylaxis against recurrences after complete transurethral resection of superficial bladder cancer. The treatment schedule, consisting of one 6- or 8-week course of instillations (50 mg epirubicin or 150 mg BCG per instillation) followed by single maintenance doses to the responders at follow-up examinations, was modified for those of the initial responders who were at high risk for recurrence and who received an additional separate 4-week course of treatment 6 months after the start of therapy.

RESULTS

Sixty percent of the patients treated with epirubicin, 68% of the patients treated with BCG, and 41% of the control subjects, who underwent resection only, remained free of recurrences for a mean follow-up of 32.9 months. The only significant difference was found between patients treated with BCG and control subjects, in favor of the former. Conversely, recurrence rate per 100 patient-months and mean interval to recurrence showed both drugs to be superior to resection alone regarding several tumor characteristics. However, a significant benefit in favor of BCG when compared with epirubicin was shown in those patients who had Stage T1 and Grade 3 tumors at presentation.

CONCLUSIONS

Intravesical epirubicin and BCG were superior to transurethral resection alone in the prophylaxis of superficial bladder cancer, but with respect to superficially invasive and high-grade tumors, BCG demonstrated a remarkable advantage.

Expression of antitumor response. Role of attachment and viability of bacillus Calmette-Guérin to bladder cancer cells

BACKGROUND

Antitumor effects of Bacillus Calmette-Guérin (BCG) against superficial urinary bladder cancer is known to be strong when BCG is directly infused into the bladder cavity. For expression of that effect, attachment of BCG to tumor cells is reported to be essential as the first step. Our study was conducted to elucidate the significance of attachment of BCG to tumor cells in inducing the antitumor effect.

METHODS

BCG, Tokyo 172 strain, in the form of live bacilli, lyophilized bacilli, or autoclaved bacilli was co-cultured with MBT-2, mouse-origin transitional cell cancer cells. Various preparations of BCG were mixed with MBT-2 cells and transplanted to male C3H/He mice to see tumor growth-inhibiting effect.

RESULTS

Both live and lyophilized BCG attached strongly to MBT-2 cells. The maximal attachment to the cells with live BCG occurred 24 hours earlier than with lyophilized BCG. When BCG was autoclaved, it lost the ability to attach to the cells. Lyophilized or autoclaved BCG exerted a marked tumor growth-inhibiting effects. This effect was equal to the Tokyo 172 strain and the Armand Frappier Canada strain. Histologically, a high degree of infiltration by macrophages was seen.

CONCLUSIONS

The results indicated that coexistence of BCG, even as killed by autoclaving, with tumor cells activates local immunity. Accordingly, the significance of the attachment of BCG to tumor cells in intravesical infusion therapy is surmised to lie in the fact that it results in retention of the BCG at the reaction site. This may provide a clue on how to approach future development of safer and more stable BCG-derived antitumor drugs.

Psoas abscess following intravesical bacillus Calmette-Guerin for bladder cancer: a case report

An 87-year-old man with an abdominal aortic aneurysm received intravesical bacillus Calmette-Guerin therapy for transitional cell carcinoma of the bladder. He presented 9 months later with a psoas abscess that mimicked a contained retroperitoneal abdominal aortic aneurysm rupture. The abscess cultures yielded Mycobacterium bovis. Recent transurethral resection and high voiding pressures after instillations of bacillus Calmette-Guerin may have led to distant dissemination of the drug.

Pharmaceutical characterization of Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccine used for the treatment of superficial bladder cancer

Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccine, developed in the 1920s as a treatment and prophylactic for tuberculosis, has proved to be a nonspecific stimulant of the immune system and is now the major form of clinical immunotherapy approved for the treatment of superficial bladder cancer in the United States. However, methods for the production and physical characterization of the vaccine have not been significantly developed since Calmette and Guérin first devised their process for attenuating the organism in 1908. When reconstituted with sterile water immediately before use, the vaccine consists of a suspension of cellular fragments and aggregates and a mixture of dead and living cells. The dose is determined by the number of colony-forming units that develop when the vaccine is allowed to grow in a nutrient medium. This measurement of dose and viability is misleading because each cellular aggregate may consist of several hundred individual cells, but only one need be living to give rise to a single visible colony. Viability should therefore be measured on the basis of residual ATP levels. In this report, the mode of action of BCG vaccine against bladder cancer is reviewed, and attention is drawn to some factors that may need to be controlled during manufacturing and subsequent quality assurance procedures. The morphology of the various parts of the complex pleomorphic life cycle of this Mycobacterium species has been investigated, and the vaccine has been physically evaluated to provide a characterization by contemporary methodologies, including measurement of ATP content and particle size distribution of the dispersed mycobacterial aggregates.

Intravesical bacillus Calmette-Guerin immunoprophylaxis of superficial bladder cancer: results of a controlled prospective trial with modified treatment schedule

A controlled prospective trial on 94 patients evaluated the efficacy of intravesical Pasteur strain bacillus Calmette-Guerin (BCG) administration as prophylaxis against tumor recurrences after complete endoscopic resection of superficial bladder cancer. The treatment schedule, consisting of an initial 6-week course of instillations and a single quarterly maintenance dose to the responders, was modified to those of the latter who were at high risk for recurrence and who received an additional separate 4-week course of therapy. The percentage of the patients treated prophylactically with BCG and who remained free of recurrences (68%, mean followup 33.8 months) was significantly higher than that of the controls who underwent transurethral resection only (41%, mean followup 30.2 months). In terms of relative risk of recurrences, recurrence rate per 100 patient-months and disease-free interval, comparisons between the 2 groups of patients revealed a significant benefit for the BCG group overall as for those subjects having stages Ta and T1 tumors, multifocal tumors, a history of disease, and grades 2 and 3 carcinoma. Drug-induced toxicity was acceptable. Our study suggests that our modified treatment protocol is notably safe and effective against recurrent superficial bladder cancer.

Intrarenal bacillus Calmette-Guerin therapy for upper urinary tract carcinoma in situ

Of 17 renal units from 11 patients treated with intrarenal bacillus Calmette-Guerin (BCG) for positive selective upper tract urine cytology 16 had negative radiographic studies and 1 had a papillary renal pelvic lesion. The standard diagnostic maneuvers were used to rule out other sources of positive cytology from the lower tracts. Six patients had bilateral involvement, 3 had prior contralateral nephroureterectomy and 2 had unilateral positive cytology but were poor surgical risks. The BCG solution was administered weekly by retrograde ureteral catheterization and instillation during 1 hour. One patient had fever during the initial treatment and received antituberculous therapy. Other side effects included transient hematuria in 3 patients and irritative urinary symptoms in most patients. Of 11 patients (12 renal units) 8 had normalization of the urinary cytology with a median followup of 36 months. One patient had unilateral conversion of the cytology result but the contralateral papillary tumor persisted, requiring nephroureterectomy. The remaining 2 patients had persistently positive cytology results and the disease progressed. Longer followup and further experience with intrarenal BCG are required before the exact role of this treatment modality in upper tract urothelial malignancies, including carcinoma in situ, can be determined.