Treatment of residual, non-infiltrating bladder cancer with bacillus Calmette-Guerin

[New therapeutic approaches for non-muscle invasive bladder cancer-is organ preservation also possible after BCG (Bacillus Calmette Guérin)?]

Bacillus Calmette-Guérin (BCG) therapy is the standard of care in the treatment of high-risk non-muscle invasive bladder cancer (NMIBC). In the absence of a response to BCG and persistent high-grade disease, cystectomy is recommended depending on the clinical risk. A variety of targeted therapy approaches, which aim at immune- and gene-based molecular targets, such as PD-(L)1 and FGFR, are currently being investigated in randomized studies for BCG-unresponsive NMIBC. Furthermore, novel forms of application for instillation therapy, such as the TAR device, in combination with gemcitabine or erdafitinib are being investigated in clinical trials in order to extend the duration of action of the active substance on the urothelium. Thus, there are now many developments that could make bladder-preserving therapy with comparable survival data possible as an alternative to BCG or in the event of BCG failure. In the future, it will be necessary to clarify how BCG response can be predicted by using molecular markers and how to define risk groups that should primarily be given an alternative therapy to BCG.

Intravesical Gene Therapy

Non-muscle-invasive bladder cancer is a challenging disease to treat, with few effective salvage intravesical options available for patients who develop bacillus Calmette-Guerin-unresponsive disease. Although radical cystectomy with pelvic lymphadenectomy remains the gold standard treatment for these patients, there remains an unmet need for other options for those who are unable or unwilling to undergo surgery. To this end, intravesical gene therapy is emerging as a potential alternative with promising early data and ongoing efforts to better understand the mechanisms of action to optimize therapy.

Immunotherapies for bladder cancer: a new hope

PURPOSE OF REVIEW

We review recent data on immunotherapies for bladder cancer and discuss strategies to maximize the antitumor effect of immunotherapy in solid tumors.

RECENT FINDINGS

Anti-programmed death ligand 1 has shown promise in advanced bladder cancer. Clinical trials of immune checkpoint inhibitors as monotherapy or in combination are underway. Here we review strategies for enhancing antitumor immunity using immunomodulating agents or combination treatments that may increase tumor response.

SUMMARY

Combining immune checkpoint inhibitors with other treatment modalities may lead to the development of new treatment strategies in advanced bladder cancer; however, identifying predictive biomarkers is essential for appropriate patient selection.

Anti-interleukin-10R1 monoclonal antibody in combination with bacillus Calmette--Guérin is protective against bladder cancer metastasis in a murine orthotopic tumour model and demonstrates systemic specific anti-tumour immunity

Effective treatment of bladder cancer with bacillus Calmette-Guérin (BCG) depends on the induction of a T helper type (Th) 1 immune response. Interleukin (IL)-10 down-regulates the Th1 response and is associated with BCG failure. In this study, we investigated whether blocking IL-10 signalling could enhance the BCG-induced Th1 response and anti-tumour immunity in a murine orthotopic tumour model. Treatment with BCG and anti-IL-10 receptor 1 monoclonal antibody (anti-IL-10R1 mAb) increased the interferon (IFN)-γ to IL-10 ratio in both splenocyte cultures and urine. Mice bearing luciferase-expressing MB49 (MB49-Luc) tumours were treated and followed for tumour growth by bioluminescent imaging, bladder weight and histology. Mice treated with phosphate-buffered saline (PBS) (group 1), BCG plus control immunoglobulin (Ig)G1 (group 2) or BCG plus anti-IL-10R1 mAb (group 3) showed 0, 6 and 22% tumour regression, respectively. The mean bladder weight of group 3 mice was substantially lower than those of groups 1 and 2 mice. Remarkably, 36% of group 1 and 53% of group 2 mice but no group 3 mice developed lung metastasis (P = 0·02). To investigate the mechanisms underlying the effect of combination therapy, splenocytes were stimulated with S12 peptide (serine mutation at codon 12 of the K-ras oncogene) known to be expressed in MB49-Luc cells. Induction of ras mutation-specific IFN-γ and cytotoxicity was observed in mice treated with combination therapy. These observations indicate that BCG, in combination with anti-IL-10R1 mAb, induces enhanced anti-tumour immunity that is protective against lung metastasis. Anti-IL-10R1 mAb demonstrates systemic effects and may prove useful in clinical practice for treating bladder cancer in high-risk patients.

Bladder Cancer Immunotherapy: BCG and Beyond

Mycobacterium bovis bacillus Calmette-Guérin (BCG) has become the predominant conservative treatment for nonmuscle invasive bladder cancer. Its mechanism of action continues to be defined but has been shown to involve a T helper type 1 (Th1) immunomodulatory response. While BCG treatment is the current standard of care, a significant proportion of patients fails or do not tolerate treatment. Therefore, many efforts have been made to identify other intravesical and immunomodulating therapeutics to use alone or in conjunction with BCG. This paper reviews the progress of basic science and clinical experience with several immunotherapeutic agents including IFN-α, IL-2, IL-12, and IL-10.

Combination of BCG and interferon intravesical immunotherapy: an update

OBJECTIVE

To provide an update on the use of interferon (IFN) in the treatment of non-muscle invasive bladder cancer (NMIBC).

METHODS

A literature review of intravesical IFN was performed.

RESULTS

In vitro evidence suggested that IFN combined with BCG may have a synergistic effect on the immune response, and treatment regimens with IFN have used reduced BCG dosage in an attempt to reduce toxicity. IFN combined with BCG may salvage some patients, single-course BCG failures or late relapsers, while those that relapse quickly may be destined to failure. However, based on the results of a recently reported randomized trial, the addition of IFN may not improve efficacy in BCG naïve patients.

CONCLUSIONS

BCG plus IFN remains an alternative in selected patients with NMIBC who fail intravesical BCG.

Reactive arthritis following BCG immunotherapy for urinary bladder carcinoma: a systematic review

Intravesical instillation of Bacillus Calmette-Guerin (BCG) is used with efficacy and safety in the treatment of patients with intermediate and high-risk superficial bladder carcinoma. Arthralgia and/or arthritis is one of the rare severe complications following intravesical BCG immunotherapy. We searched MEDLINE in order to analyze the frequency of this clinical complication, its pathogenesis and outcome. The electronic search was conducted using the following key words: "BCG immunotherapy" and "Arthritis, arthralgias and BCG immunotherapy". At the end of a process of abstract analysis, 48 papers were included in the systematic review. All the selected papers, except one that was a clinical review, described at least one case of arthritis after BCG therapy. The BCG immunotherapy resulted to be safe and efficacious in the treatment of bladder cancer; the development of reactive arthritis is rare and can evolve in a chronic process. The review of the literature highlighted that reactive arthritis following BCG intravesical instillation is a complication usually well controlled with the discontinuation of the immunotherapy and nonsteroidal anti-inflammatory drugs (NSAIDs) treatment. Only a small portion of patients with a particular genetic background will develop a chronic process.

Bacillus Calmete-Guérin plus interferon-alpha2B intravesical therapy maintains an extended treatment plan for superficial bladder cancer with minimal toxicity

Bacillus Calmette-Guérin (BCG) and interferon-alpha2B (IFN-alpha2B) have both been individually used for the intravesical treatment of superficial bladder cancer. We report our experience on the therapeutic efficacy and toxicity of combined intravesical BCG plus IFN-alpha2B for treating superficial bladder cancer, including patients failing previous BCG therapy. Thirty-two patients with superficial bladder cancer underwent 6 weekly treatments with full-, one-third, or one-tenth-dose of BCG plus 50 or 100 MU of IFN-alpha2B based on prior BCG exposure and tolerance. Patients with no evidence of disease proceeded onto maintenance therapy of 3 weekly treatments at 3 months followed by 2 additional maintenance cycles given 6 months apart. Response was assessed by cystoscopy/biopsy every 3 months after treatment. Before BCG plus IFN-alpha2B treatment, 20 patients (63%) had previously failed intravesical BCG therapy, 27 (84%) had aggressive disease (stage T1, grade 3, or carcinoma in situ), 27 (84%) had recurrent disease, 14 (44%) had multifocal disease, and 6 (19%) had disease of over 4 years duration. At median follow-up of 22 months, 21 patients (66%) remain disease-free and 11 patients (34%) had disease-recurrence. Nineteen of 32 patients (59%) were disease-free after the initial induction cycle. Six of 11 patients 55% ultimately failing combination therapy did so at the first 3 to 4 month evaluation. Four of 7 patients (57%) benefited from salvage re-induction therapy. Of the 20 patients previously treated with BCG, 12 patients (60%) remain disease-free. Combination BCG plus IFN-alpha2B intravesical therapy was well tolerated. Combination intravesical BCG plus IFN-alpha2B is an effective and tolerable alternative for patients with superficial bladder cancer, including those patients in whom intravesical BCG therapy had previously failed. Benefits of this combination therapy may include potentially less morbidity, improved clinical efficacy, and in the long term, fewer patients undergoing radical therapy. However, radical treatment options should be pursued for early failures of this combination regimen in those patients with risk factors for recurrence and progression.

Immunotherapy for bladder cancer

The primary role of immunotherapy for bladder cancer is to treat superficial transitional cell carcinomas (ie, carcinoma in situ, Ta, and T1). Immunotherapy in the form of bacille Calmette-Guérin (BCG), interferon, bropirimine, keyhole limpet hemocyanin, and gene therapy is intended to treat existing or residual tumor, to prevent recurrence of tumor, to prevent progression of disease, and to prolong survival of patients. Presently, BCG is commonly used and is the most effective immunotherapeutic agent against superficial transitional cell carcinoma. Data support that BCG has a positive impact on tumor recurrence, disease progression, and survival. Proper attention to maintenance schedules, route of administration, dosing, strains, and viability is essential to obtain the maximum benefits of BCG immunotherapy. This review highlights and summarizes the recent advances concerning immunotherapy, with special emphasis on BCG therapy for transitional cell carcinoma.

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.

Nitric oxide is an important mediator for tumoricidal activity in vivo

When cultured in vitro, peritoneal macrophages, obtained from mice previously inoculated with bacillus Calmette-Guérin, release nitric oxide, which is cytostatic and/or cytolytic for tumor cells. However, it is not known whether nitric oxide has antitumor effects in vivo. Here we demonstrate that nitric oxide is an important mediator of host resistance to syngeneic and xenogeneic ovarian tumor grafts in C3HeB/FeJ mice. A murine ovarian teratocarcinoma cell line, utilized to study the mechanism of bacillus Calmette-Guérin-induced host resistance to a syngeneic ovarian tumor, proliferated when transplanted intraperitoneally. Marked tumoricidal activity was observed, however, when these murine ovarian teratocarcinoma cells were transplanted 8 days after intraperitoneal bacillus Calmette-Guérin inoculation. In studies related to xenogeneic ovarian tumor grafts, tumoricidal activity was observed after intraperitoneal transplantation of a human epithelial ovarian cancer cell line, NIH:OVCAR-3. This cell line proliferates only in athymic nude (immunologically incompetent) mice. In both sets of experiments, tumoricidal activity was reduced by inhibition of nitric oxide synthesis. These results demonstrate the tumoricidal action of nitric oxide in vivo.

Adjuvant intravesical therapy for superficial bladder cancer

OBJECTIVE

To review the results of clinical trials and adverse drug effects of thiotepa, BCG vaccine, mitomycin, and doxorubicin, which are used as adjuvant intravesical therapy for superficial bladder cancer.

DATA SOURCE

Information was retrieved from a MEDLINE search, of the English-language literature. Indexing terms included adjuvant pharmaceutics, bladder neoplasms, thiotepa, mitomycin, BCG vaccine, and doxorubicin.

DATA EXTRACTION

Data from several human and in vitro studies were assessed and evaluated, according to the strength of comparative data and therapeutic response.

STUDY SELECTION

Emphasis was placed on clinical trials that assessed and evaluated dosage, therapeutic regimens, and therapeutic response of adjuvant intravesical therapy for superficial bladder cancer.

DATA SYNTHESIS

Adjuvant intravesical therapy and long-term prophylaxis are effective for superficial bladder cancer. Studies have shown that doxorubicin, thiotepa, BCG, and mitomycin, when used as adjuvant therapy, provide better protection than transurethral resection alone against tumor recurrence and prolong the time to when cystectomy is required.

CONCLUSIONS

Several randomized clinical trials suggest that BCG is superior to thiotepa, doxorubicin, and mitomycin in preventing bladder tumor recurrence and tumor progression. Local cystitis is an adverse effect produced by all four agents; however, BCG vaccine has been reported to cause a higher incidence of adverse reactions (e.g., dysuria, hematuria). BCG may also cause an influenza-like syndrome, arthralgias, and fever, but most of these reactions have resulted in few severe adverse effects when the drug is given in the relatively modest recommended doses.

BCG and the treatment of superficial bladder cancer

In this report, we review the evolution of bacillus Calmette-Guérin (BCG) immunotherapy as a legitimate form of treatment in superficial, nonmuscle-invasive bladder cancer. In the US, an estimated 45,000 new cases of bladder cancer are diagnosed each year and the annual death rate approaches 11,000. Approximately 70 percent of these cancers are superficial at the time of initial presentation. The treatment of superficial bladder cancer has three objectives: (1) eradication of existing disease, (2) prophylaxis against tumor recurrence, and (3) prevention of tumor progression (either muscular invasion, metastatic spread, or both). Cystectomy generally is reserved for muscle-invasive disease. Transurethral resection of the bladder tumor is the preferred initial therapy. Intravesical instillations of various chemotherapeutic agents following transurethral resection have been extensively investigated. Some of the common agents used include thiotepa, mitomycin, and doxorubicin. Despite such treatment efforts, however, over 40 percent of patients with superficial bladder cancer experience a recurrence of their tumor within three years. Approximately half of these recurrences either present as less-well-differentiated tumors or have already penetrated into the bladder musculature, metastasized, or both. Since Morales et al. first introduced intravesical BCG vaccine for prophylaxis as well as for treatment of superficial bladder tumors in 1976, support has grown rapidly for its use as an alternative to chemotherapy. When used with prophylactic intent following transurethral resection, recurrence rates are lower than those achieved with other agents. In addition, BCG is emerging as the consensus drug of choice for treating carcinoma in situ of the bladder. The mechanisms by which BCG exerts its antitumor activity remain largely unknown. BCG is thought to stimulate a localized, nonspecific inflammatory response that leads to subsequent shedding of tumor cells. A large body of clinical and experimental data suggest an association between the development of an immunologic response to BCG and successful antitumor activity. No universally accepted therapeutic regimen has been agreed upon. One regimen commonly used consists of an ampul of BCG mixed with 50 mL of NaCl 0.9%, instilled once a week for six weeks and retained for two hours prior to voiding. Maintenance therapy generally consists of intravesical doses given at three-month cycles for at least two years of recurrence-free follow-up. Because BCG is a biologic agent, the commercially available products may differ in weight, colony-forming units per vial, and antigenicity. How these product characteristics affect clinical responsiveness to different strains of BCG remains unanswered.

Oral or intravesical bacillus Calmette-Guerin immunoprophylaxis in bladder carcinoma

A total of 71 patients with superficial transitional cell carcinoma underwent transurethral resection of bladder tumor. All patients had stage pTa or pT1 transitional cell carcinoma or carcinoma in situ without other concurrent malignancies. The patients were assigned to 3 treatment groups: control group--transurethral resection discontinued within the study, oral bacillus Calmette-Guerin (BCG) group--transurethral resection of bladder tumor plus BCG (Moreau) and intravesical BCG group--transurethral resection of bladder tumor plus BCG. Of 9 patients in the control group 8 (89%) experienced tumor recurrence during a mean followup of 20 months. Of the 28 patients in the oral BCG group 11 (39.3%) had recurrence during a mean followup of 36 months. Of the 34 patients in the intravesical group 6 (18%) had recurrence in a 24-month mean followup. The incidence of complications was higher in the intravesical (41.2%) than in the oral BCG group (28.5%). These results show that intravesical BCG is a more effective immunotherapy; however, oral BCG can be used in patients who do not accept intravesical BCG administration.

Immunotherapy of bovine ocular squamous cell carcinoma by repeated intralesional injections of live bacillus Calmette-Guérin (BCG) or BCG cell walls

Thirty cows of the Dutch Friesian and the Maas-Rijn-Ijssel breed with histologically confirmed ocular squamous cell carcinoma were treated by repeated intralesional injection of live bacillus Calmette-Guérin (BCG) (n = 14) or a BCG cell-wall vaccine (n = 16). Complete regression of the primary tumour was observed in 64% and 57% of the animals respectively. In the 2-year follow-up period there was no recurrence of primary tumours. This sharply contrasts with the recurrence frequency (40%-50%) after complete remission induced by a single intralesional injection with BCG, observed in an earlier study. In 1 animal a new primary tumour developed. At necropsy metastases were present in 33% of the treated animals: in 3 of 17 animals that showed complete regression of the primary tumour and in 7 of 13 animals with partial regression or progressive disease. This did not differ significantly from results obtained after a single treatment (27%). Delayed-type hypersensitivity to M. bovis purified protein derivative (PPD) was more persistent in animals showing regression of the primary tumour than in non-responding animals. Of the animals with a positive PPD response 6 months after treatment, 79% showed tumour regression. Regression was observed in only 28% of the animals not responding to PPD after the same period of time.

IN CONCLUSION

(a) recurrence of the primary tumour was not observed after repeated BCG treatment; (b) the frequency of metastases was not decreased compared to results obtained with a single treatment; (c) regression was correlated with a positive delayed-type hypersensitivity reaction to PPD (P less than 0.05) 6 months after treatment; (d) no significant differences were observed when the clinical results of treatment with live BCG and the BCG cell wall vaccine were compared.

Reduced bladder capacity in patients receiving intravesical chemoprophylaxis with mitomycin C

After complete resection of superficial bladder carcinoma (Tis-2, G1-3), 75 patients were treated prophylactically with either 20 or 30 mg mitomycin C. Six patients developed a substantial reduction in bladder capacity (less than 200 ml). In 2 patients radical cystectomy of an otherwise tumour-free fibrotic bladder was necessary. The results of long-term treatment (2 years) suggest that reduced bladder capacity correlates with the cumulative dosage of mitomycin C.

BCG in management of superficial bladder cancer

Superficial bladder cancer and particularly carcinoma in situ has the potential for invasiveness for which the treatment is cystectomy with a resultant disappointing 50 per cent five-year survival and urinary diversion with a certain diminished quality of life. BCG therapy is a new method of treating aggressive superficial bladder cancer with better response rates than conventional chemotherapy. It may be immunologically mediated and, if so, may be the first major success of a therapeutic modality that offers less morbidity than the currently standard options of surgery, radiotherapy, or chemotherapy.

Toxicity of intravesical BCG and its management in patients with superficial bladder tumors

Toxicity of bacillus Calmette-Guerin (BCG) Pasteur strain, given in a dose of 120 mg once a week for 6 weeks, was retrospectively evaluated in a study of 107 patients with recurrent superficial bladder cancer. Only six patients had no symptoms of toxicity. Severe cystitis (ten patients) was most likely to occur in those with decreased bladder compliance before treatment. Systemic symptoms resembling those of influenza (flu) were severe in six patients. Potentially serious complications occurred in six patients. Overall, toxic reactions were mild and self limited, and toxicity often could be easily managed by a reduction in the BCG dose (17 patients), temporary interruption of treatment (five patients), or cessation (four patients). Late occurrence of bladder granulomas (32 patients) and cystoscopic appearance of significant cystitis (55 patients) did not correlate with posttreatment voiding symptoms, and these changes were temporary and confined to the first 6 months after treatment. There were no cases of late bladder contracture, and none of the patients free of voiding symptoms before treatment had such symptoms afterward. Extravesical granulomas were observed in 37 patients and were the cause of obstruction of the urinary tract in nine. Pretreatment skin reactivity did not correlate with toxicity, and concurrent percutaneous administration of BCG had no effect on toxicity. BCG has a cumulative effect, so increased toxicity is to be expected during long-term administration. BCG toxicity is primarily a response of the cell-mediated immune system, and transient local or systemic infection appears to be important. This fact suggests that immunosuppression is a relative contraindication to BCG use.

Superiority of intravesical immunotherapy with Corynebacterium parvum and Allium sativum in control of murine bladder cancer

Intravesical immunotherapy with bacillus Calmette-Guerin (BCG), Corynebacterium parvum (CP), keyhole limpet hemocyanin (KLH), and an extract of Allium sativum (AS) was studied in mice transplanted intravesically with mouse bladder tumor cells (MBT-2). Female C3H/He mice were anesthetized with sodium pentobarbital. Two X 10(5) MBT-2 cells were delivered into the bladder transurethrally using a small catheter, immediately after the posterior wall of the bladder had been electrocauterized. Bladder tumor became palpable or demonstrable microscopically in two weeks. Immunotherapy with BCG (2 X 10(6) CFU), CP (250 micrograms), KLH (50 micrograms), or AS (25 mg) was administered directly into the bladder via urethral catheter on day 1, day 6, or days 1 and 6. On day 21 the bladders and spleens were excised and weighed, and the bladders were examined macroscopically and microscopically for evidence of tumor. The results of the study showed that two treatments given one and six days after tumor transplant yielded the lowest tumor incidence and that CP and AS appeared equally effective or even slightly more effective than BCG in this model. These results suggest that clinical evaluation of CP or AS may be worthwhile.

The effects of intravesical and intradermal application of a new B.C.G. on the dog bladder

Intravesical and intradermal application of B.C.G. (Bacillus Calmette Guérin) has proven to be effective in the prophylaxis of recurrence of superficial bladder carcinoma after transurethral resection and in the treatment of carcinoma in situ (C.I.S.) in man. Different strains of B.C.G. have been used for this purpose. In this article a new strain of B.C.G. (B.C.G.-R.I.V.M.) has been tested to assess its toxicity. The effects of intravesical and intradermal application of B.C.G.-R.I.V.M. were studied on normal and on coagulated canine urothelium. In this study no general side effects of B.C.G.-R.I.V.M. were seen. Only minor local changes occurred in the bladder wall. Small granulomas were found in the suburothelial tissue. No granulomas or signs of active inflammation were observed in the pelvic lymphnodes, spleen and liver. Because B.C.G.-R.I.V.M. seemed to be a safe agent in the dog we have started to use it for prophylaxis in superficial bladder cancer in man.

Superiority of intralesional immunotherapy with Corynebacterium parvum and Allium sativum in control of murine transitional cell carcinoma

Immunotherapy with bacillus Calmette-Guerin (BCG), Corynebacterium parvum (CP), keyhole limpet hemocyanin (KLH) and an extract of Allium sativum (AS) was studied in a transitional cell carcinoma (MBT-2) in mice. Comparison was made between intraperitoneal (IP) versus intralesional (IL) administration of these agents. C3H/He mice were transplanted subcutaneously in the hind limb with 5 X 10(4) tumor cells. After transplantation, mice were randomized into groups to receive either IP or IL treatments with BCG (2 X 10(6) CFU), CP (250 micrograms.), KLH (50 micrograms.) or AS (25 mg.). At weekly intervals the tumor volume was determined. To assess the local cellular events following these treatments, histopathological studies were performed 10 days after tumor transplant with tissues removed from the injected sites. IL route was much more effective than IP route in inhibiting tumor growth. CP and AS exhibited more significant therapeutic effect than BCG or KLH. No tumor developed in mice which received five IL treatments of CP or AS. The data indicate that CP or AS may serve as effective biological response modifiers in controlling transitional cell carcinoma. The study further emphasizes that route and frequency of administration are crucial variables determining efficacy of immunotherapy.

Bacillus Calmette-Guerin for superficial transitional cell carcinoma of the bladder

Pasteur strain bacillus Calmette-Guerin was used to treat superficial transitional cell carcinoma of the bladder in 28 patients. Patients selected for treatment had an incomplete resection, positive selected site biopsies and/or post-resection positive cytology findings. Complete response required negative histology and cytology findings at cystoscopic followup 4 to 8 weeks after completion of treatment. Of the patients 20 (71 per cent) demonstrated a complete response, including all 6 with carcinoma in situ. Results converted to negative in 16 of 17 patients with positive urine cytology findings and 4 with positive prostatic urethral biopsies. Of the responders 8 had received prior treatment with thiotepa. The treatment regimen of 120 mg. Pasteur strain bacillus Calmette-Guerin weekly for 6 weeks was well tolerated. It was necessary to limit the number of treatments to 5 because of local irritative effects in only 3 patients. No chronic bladder disability has been noted during followup of 3 to 30 months. This experience supports the efficacy of bacillus Calmette-Guerin as a cost-effective, well tolerated treatment modality for patients with superficial transitional cell carcinoma of the bladder.

Intravesical bacillus Calmette-Guerin therapy for superficial bladder cancer: effect of bacillus Calmette-Guerin viability on treatment results

We treated 40 patients with superficial bladder cancer via intravesical bacillus Calmette-Guerin for 1) prophylaxis against tumor recurrence, 2) residual carcinoma or 3) flat carcinoma in situ. A single course of intravesical bacillus Calmette-Guerin therapy was successful in 6 of 11 patients (55 per cent) treated for residual carcinoma and 6 of 12 (50 per cent) treated for carcinoma in situ. Of 17 patients receiving a single course of bacillus Calmette-Guerin for prophylaxis 11 remained free of tumor during short-term followup. A second course of therapy was administered to failures in each treatment category, which resulted in favorable responses in 5 of 6 patients treated for prophylaxis, 2 of 5 treated for residual tumor and 3 of 6 treated for carcinoma in situ. Over-all complete responses were achieved in 16 of 17 patients (94 per cent) treated for prophylaxis, 8 of 11 (73 per cent) for residual carcinoma and 8 of 12 (66 per cent) for carcinoma in situ, with a mean followup from the final treatment of 9.3, 12.3 and 7.9 months, respectively. Favorable results occurred more frequently among patients who exhibited a granulomatous inflammatory response in the bladder and delayed hypersensitivity skin test response to purified protein derivative. Marked variability in viability of bacillus Calmette-Guerin organisms was observed among different lots of bacillus Calmette-Guerin, and a direct relationship was observed between bacillus Calmette-Guerin vaccine viability and therapeutic efficacy. Most patients who failed initial therapy with a low viability lot of bacillus Calmette-Guerin responded favorably to re-treatment with a higher viability lot. The results suggest that the level of viability of each lot of bacillus Calmette-Guerin vaccine should be verified before clinical use.

The management of superficial bladder tumors and carcinoma in situ with intravesical bacillus Calmette-Guerin

A phase II study was performed to assess the role of bacillus Calmette-Guerin as a prophylaxis against recurrent stages O and A bladder tumors, and in the treatment of existing superficial bladder tumors and carcinoma in situ. Tice strain bacillus Calmette-Guerin (1 vial, 2 to 8 times 10(8) organisms in 60 cc saline) was instilled intravesically without cutaneous inoculation. Instillations were given weekly for 6 weeks and then monthly or until recurrence in 22 patients with a history of recurrent tumors, while 22 with existing stages O and A transitional cell carcinoma, and 19 with carcinoma in situ were treated weekly for 8 weeks and then monthly for 12 months or until failure. Complications included cystitis in 88 per cent of the patients (severe in 20 per cent), fever in 15 per cent, a flu-like syndrome in 13 per cent, edema and pruritus in 1.5 per cent, and ureteral stenosis in 1.5 per cent. Twelve patients (19 per cent) did not complete the study owing to toxicity. Of the patients in the prophylaxis group 67 per cent have had no tumor recurrence 10 to 26 months (mean 15 months) after therapy. Of the patients with existing tumors 36 per cent had complete regression following bacillus Calmette-Guerin therapy and 23 per cent had a partial response. Among the patients with carcinoma in situ 13 (68 per cent) had reversal to normal urothelium and 3 (16 per cent) had marked improvement. None of the patients had recurrence at 11 to 20 months. Intravesical Tice strain bacillus Calmette-Guerin is effective as a prophylaxis against recurrent superficial bladder tumors and in the treatment of carcinoma in situ.

Bacillus Calmette-Guerin immunotherapy of infiltrating bladder cancer

Oral administration of bacillus Calmette-Guerin was used to treat 10 patients with muscle invasive transitional cell carcinoma of the bladder. The treatment induced tumor regression in 7 patients (70 per cent), including 1 who died without evidence of recurrent tumor. Skin test reactivity was correlated with response to treatment. Only 1 patient had marked skin test reactivity at the time of tumor recurrence. Our data demonstrated that patients with invasive bladder cancer may derive benefit from immunotherapy.

Treatment of superficial bladder tumors in a controlled trial with thio-TEPA versus adriamycin

Forty-six patients with superficial transitional cell carcinoma of the bladder were randomized into two groups. Thio-TEPA or adriamycin were instilled periodically into the bladder and cystoscopic follow up was carried out. Both thio-TEPA and adriamycin proved to have similar efficacy in delaying tumor recurrence. Further investigations to establish better dose and interval schedules are indicated.

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

Clinical studies on intracavitary bacillus Calmette-Guerin therapy for bladder cancer have been conducted at this institution for more than 10 years. The 82 patients treated for prophylaxis of multiple superficial recurrences, residual tumors or carcinoma in situ have been followed for 2 to 7 years after treatment. The long-term results confirm previous studies showing the effectiveness of bacillus Calmette-Guerin in the prophylaxis and therapy of superficial vesical neoplasms. However, some decrease is observed in the population free of disease with a prolonged followup. Recent modifications in the original protocol have been introduced to enhance the effectiveness of the vaccine. Side effects during or shortly after treatment were minor and self-limiting in the large majority of patients (fever, bladder irritability and hematuria). Mild, transient hepatic dysfunction was noted in 2 patients. Hematological disturbances were insignificant. No patient had permanent structural or functional alterations of the bladder.

Comparison of the efficacy of intravesical Bacillus Calmette-Guérin with thiotepa, mitomycin C, poly I:C/poly-L-lysine and cis platinum in murine bladder cancer

The efficacy of intravesical Bacillus Calmette-Guérin for the treatment of the mouse bladder tumor MBT-2 was compared with that of thiotepa, mitomycin C, cis-diamminedichloroplatinum II and poly I:C/poly-L-lysine. MBT-2 cells were instilled into the bladder immediately after electrocauterization. Drug instillations were initiated 24 hours later and continued on a weekly basis for 4 weeks. Both Bacillus Calmette-Guérin and cis-diamminedichloroplatinum II significantly (p less than .0004) inhibited MBT-2 tumor implantation when compared to diluent-treated controls. Neither mitomycin C, thiotepa nor poly I:C/poly-L-lysine significantly inhibited tumor implantation. Mean tumor weights also were significantly (p less than .05) reduced in Bacillus Calmette-Guérin and cis-diamminedichloroplatinum II-treated mice, while tumor mean weights in mice treated with thiotepa, mitomycin C or poly I:C/poly-L-lysine were not significantly different than controls. These results suggest that the efficacy of intravesical Bacillus Calmette-Guérin in comparison with other drugs in the MBT-2 mouse bladder tumor model is similar to observations reported in human clinical trials in which intravesical Bacillus Calmette-Guérin was shown to be more effective than other cytotoxic drugs. These data further support the utility of the MBT-2 model for the study of the mechanisms by which Bacillus Calmette-Guérin inhibits bladder tumor growth.

Bladder instillation of adriamycin in the treatment of bladder cancer

Intravesical Adriamycin instillation was used in 10 patients with transitional cell carcinoma of the bladder as postoperative prophylactic treatment against recurrence. The protocol for bladder instillation was 20 mg/10 ml of Adriamycin twice weekly for a total of eight doses. One patient developed recurrence in 3 months and three, in 6 months. The main local side-effects were frequency and dysuria which occurred in four cases. Leukopenia and increased SGOT and SGPT values each occurred in one case. No cases of cardiotoxicity, fibrosis, or atrophy of the bladder mucosa were found. Further studies are necessary to achieve the best possible results.

Clinical application of a whole blood assay for human natural killer (NK) cell activity

A whole blood assay for assessment of spontaneous or NK-cell activity has been proposed in order to avoid many of the problems encountered with the conventional methods involving cell separation procedures. Normal subjects and patients with cancer of the kidney or bladder were investigated with the new method. Cancer patients were found to exhibit significantly lower levels of reactivity when compared to normal subjects; furthermore, the results were consistent with the common belief that tumor burden and NK activity were inversely related. The whole blood assay appears useful in monitoring cancer patients, particularly those treated with immune modulators.

Chemoimmunotherapy of implanted murine bladder cancer

The unaltered incidence of recurrence of superficial bladder tumor after discontinuation of intravesical chemotherapy has prompted a search for effective adjuvant therapy. The technique of cauterization and implantation of tumor cells was performed in C3H/He mice to simulate the early stage of bladder cancer to evaluate a regimen of intravesical mitomycin C followed by the systemic immunopotentiator, levamisole. Mice received either normal saline (control), mitomycin C (MMC), levamisole (Leva), or MMC plus Leva. Chemotherapy was given intravesically on days 6 and 13. Immunotherapy was given intraperitoneally on days 7 and 14. All mice were sacrificed on day 21. In the treatment groups, the incidences of bladder tumor varied from 50 to 63 per cent whereas that of the control group was 91 per cent. An increase in spleen weight was observed in the treatment groups of Leva and MMC plus Leva as well as the control group but not observed in the group receiving MMC. Our study suggests that although Leva did not reduce the tumor incidence, an immunostimulator might be of benefit when used in conjunction with MMC.