PRINCIPLES OF INTRAVESICAL CHEMOTHERAPY AND IMMUNOTHERAPY

Stage T1 adenocarcinoma of the urinary bladder--complete response after transurethral resection and intravesical bacillus Calmette-Guerin

OBJECTIVE

To report the results of treatment of adenocarcinoma of the urinary bladder with transurethral resection and intravesical bacillus Calmette-Guerin (BCG).

METHODS

Out of 183 patients in our department treated with BCG between 1992 and 1996, three patients had adenocarcinoma, stage T1.

RESULTS

All three patients had normal cystoscopy and negative cytology 53-82 months after the start of treatment.

CONCLUSIONS

BCG appears to be effective not only in the treatment of transitional cell carcinoma, but also in adenocarcinoma of the bladder.

An overview of the treatment of superficial bladder cancer. Intravesical chemotherapy

Superficial bladder cancer accounts for approximately 70% to 80% of all newly diagnosed bladder cancers. The vast majority of these cancers are transitional bladder tumors of various histologic grades (I to III). Superficial tumors include carcinoma in situ (CIS), tumors confined to the epithelium (Ta), and superficial tumors that invade the lamina propria (T1) but do not involve superficial muscle layers. The primary treatment for eradication of stage Ta and T1 bladder cancers is transurethral resection of the tumor. Many patients with superficial bladder tumors treated with endoscopic surgery alone have recurrence or tumor progression at some point in their follow-up, and, in these patients, the need for adjuvant treatment becomes a major concern.

Interferons and bladder cancer

With the introduction of BCG, intravesical instillation of immunotherapeutic agents has become a mainstay of therapy in the treatment of superficial bladder cancer. Interferon is capable of inducing a non-specific cellular and humoral immune response towards tumor cells. It has shown promise in reducing the recurrence and progression rates of superficial bladder cancer. In contrast to BCG, intravesical interferon is associated with minimal side effects and a very low dropout rate. Current research has focused on the use of interferon in combination with immunotherapeutic and cytotoxic drugs.

[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.

Intravesical therapy for transitional cell carcinoma of the bladder: the community practice

OBJECTIVES

To assess how the community urologist employs intravesical therapy in patients with transitional cell carcinoma (TCC) of the bladder because most data on intravesical therapy reflect the experience of major referral centers.

METHODS

The medical records of 234 consecutive patients with TCC were reviewed. Sixty-nine patients received intravesical treatment before referral. The initial pathologic findings, the indication for treatment (eg, grade and stage, initial versus recurrent tumor), the schedule of intravesical therapy, and the drug selected for each course of treatment were assessed.

RESULTS

A total of 1 39 courses of intravesical treatment were given to 69 patients; thus, the avarage number of courses was 2.02 per patient. The drug used was bacillus Calmette-Guerin (BCG) in 81 (58%), mitomycin C in 34 (24%), thiotepa in 16 (12%), Adriamycin in 4 (3%), and unknown in 4 (3%). Intravesical treatment was given after transurethral resection of the initial tumor in 33 patients; the initial pathologic finding was high grade (ie, grade 3 or carcinoma in situ) and/or Stage T1 in 22, TaG1-G2 in 9, and unknown in 2. One course of treatment was administered to 34 patients (49%) and two or more courses to 35 patients (51%). Eleven patients with TaG 1 -2 tumors were treated repetitively despite failure, with an average of 3.5 courses per patient; the drug used was BCG in 44%. Nineteen percent of patients received maintenance therapy. Intravesical therapy had to be discontinued in 10 patients because of side effects; 8 patients (12%) developed small contracted bladders and severe irritative symptoms, 3 required cystectomy despite the lack of bladder cancer.

CONCLUSIONS

Intravesical therapy in community practice conforms with the generally accepted indications for high-grade and T1 disease. However, the use of BCG for low-grade TCC appears to be quite common. Repeated courses may result in significant side effects. We emphasize that excessive treatment should be avoided for low-grade, Ta lesions and BCG reserved for patients with TaG3, carcinoma in situ, or T1 TCC.

Intravesical immunoprophylaxis in recurrent superficial bladder cancer (Stage T1): multicenter trial comparing bacille Calmette-Guérin and interferon-alpha

OBJECTIVES

To estimate and compare recurrence rates, index of recurrence, and disease-free interval in patients with superficial recurrent bladder cancer receiving bacille Calmette-Guérin (BCG) or interferon (IFN) for immunoprophylaxis.

METHODS

One hundred twenty-two patients with recurrent superficial Stage pT1, grade 1 to 3 tumors were enrolled in a randomized, prospective, multicenter trial with two treatment arms of endovesical immunoprophylaxis: 150 mg of BCG versus 54 MU of recombinant IFN-alpha-2a. Administration was weekly during the first month, biweekly for 2 months, and monthly for 9 months. Both groups were similar with regard to tumor stage, grade, size, and number.

RESULTS

Sixty-one patients were evaluable in the BCG group and 49 in the IFN group. Tumors recurred in 34 (69.4%) of 49 patients in the IFN group (890 months of follow-up) and in 24 (39.3%) of 61 in the BCG group (1272 months of follow-up). The total number of recurrences (28 for BCG, 47 for IFN), disease-free interval (mean 19.3 months for BCG, 15.3 months for IFN), and index of recurrence (2.2 for BCG, 5.5 for IFN) were statistically significant (P = 0.001) in favor of BCG. Progression to invasive carcinoma was similar in both study arms. Neither systemic nor local side effects were seen in the IFN group. However, the previously reported toxicity of BCG was confirmed.

CONCLUSIONS

According to our trial, BCG remains the most efficacious agent for immunoprophylaxis of recurrent superficial bladder tumors.

Correlation of nuclear p53 over-expression with clinical and histopathological features of transitional cell bladder cancer

Forty-four pathologic specimens of 39 bladder cancer patients were analyzed immunohistochemically with D07 monoclonal antibody to detect over-expression of mutant p53 gene. The findings were interpreted by correlating with patient age, sex, cigarette smoking, number and macroscopic appearance of tumour, histological tumour grade, muscular invasion, vascular invasion, necrosis and urothelial atypia or dysplasia. Mutant p53 gene was over-expressed in 8 (18.2%) specimens. Statistically significant correlation with grade, vascular invasion, necrosis and patient sex was found with p53 over-expression. Available follow-up data were insufficient to draw a conclusion about the prognostic role of p53 over-expression. Prospective studies with larger number of patients are needed to define the exact place of nuclear p53 over-expression in transitional cell bladder cancer.

The use of the BTA Test in the detection of persistent or recurrent transitional-cell cancer of the bladder

The BTA Test1 is an adjunctive test for the diagnosis and management of bladder cancer. For estimation of its potential in the management of patients with transitional-cell cancer (TCC) a review of published results was undertaken. Three prospective studies were analyzed, in which a total of 699 patients with a history of TCC were enrolled. The BTA Test was performed on voided urine and compared with either voided-urine or bladder-wash cytologic analysis in a blinded fashion. In all three studies the sensitivity of the BTA Test was more than double that of cytology, irrespective of whether the cytologic analysis was performed on voided or bladder-wash samples. The third study also included an additional 225 patients undergoing evaluation for hematuria, and TCC was found in 67 cases. The BTA Test detected 70% of these tumors, whereas cytology detected only 25%. The BTA Test is a simple, rapid test that can diagnose a substantial percentage of patients having new or recurrent bladder TCC. Its complete role in the management of such patients remains to be defined.

Immunolocalization of transitional cell carcinoma of the bladder with intravesically administered technetium-99m labelled HMFG1 monoclonal antibody

The aim of this study was the immunolocalization of transitional cell carcinoma of the bladder with a radiolabelled murine tumour-associated monoclonal antibody and the measurement of the absolute uptake of the antibody by the tumour. Fourteen patients with transitional cell carcinoma of the bladder received 3-6 mCi (111-222 MBq) of technetium-99m labelled HMFG1 monoclonal antibody intravesically and one patient, 2 mCi (74 MBq) of iodine-131 labelled 11.4.1, which is a non-tumour-specific monoclonal antibody. Four of the 15 patients were evaluated with single-photon emission tomography (SPET) 1 1/2 to 2 h post administration. All patients underwent transurethral resection of the bladder tumour within 12-20 h following intravesical administration of the radiolabelled antibody. The radioactivity of biopsy specimens from normal urothelium and tumour areas were counted in a gamma counter. The mean uptake of the radiolabelled antibodies from normal and tumour sites was expressed as a percentage of the administered dose per kilogram of tissue. Conventional histology and immunohistochemistry using HMFG1 monoclonal antibody were performed on paraffin sections of the biopsy specimens. Although our results are preliminary, it can be concluded that: (a) bladder tumours are well imaged by SPET when using 99mTc-HMFG1; (b) intravesically administered radiolabelled antibody remains on the bladder tissue and does not escape into the systemic circulation; (c) the wide range of tumour uptake values (0%-9.3% administered dose/kg) observed probably can be attributed to heterogeneity of the antigenic expression of the tumour; (d) values of 99mTc-HMFG1 monoclonal antibody uptake by the tumour do not justify future attempts at radioimmunotherapy.

Postoperative cytology in relation to recurrences of superficial bladder tumours

TNM classification allows only a partial estimation of future tumour behaviour after surgery. More knowledge on malignant potential is needed. Spreading of viable tumour cells during transurethral resection (TUR) and their possible subsequent implantation in the bladder mucosa should be an important factor influencing duration of the tumour-free interval (TFI). A total of 1384 fresh urine samples sequentially taken after surgery from 356 patients were examined in a cytological laboratory. Data analysis confirmed significant differences in TFI between the groups with negative, suspicious and positive cytology. The higher the cytological abnormalities the shorter was TFI, regardless of which histopathological tumour grade has been verified.

Intravesical bacillus Calmette-Guerin for superficial bladder cancer: experience with Danish 1331 strain

A total of 95 patients with stage Ta/T1 superficial bladder cancer was eligible for intravesical bacillus Calmette-Guerin (BCG) immunoprophylaxis according to the standard high risk criteria for tumor recurrence and progression. Of these patients 50 agreed to undergo treatment while the remaining 45 refused any intravesical therapy and served as concurrent nonrandomized controls. The patient and tumor characteristics in the 2 groups of patients were identical. All patients underwent complete transurethral resection of the bladder tumor. Therapy consisted of 120 mg. weekly instillations of BCG (Danish 1331 strain) for 6 weeks. Among the 50 patients 33 received BCG initially while 17 received it after failure of intravesical chemotherapy. Responses were evaluated according to standard criteria. Recurrence was noted in 24 patients (48%) in the BCG group compared to 38 (84.4%) in the control group. The recurrence rates per year and per 100 patient-months were significantly reduced in the BCG arm compared to the control arm. The mean interval to first recurrence and the mean recurrence interval were significantly increased in the BCG arm compared to the control arm. The relative risk of recurrence in the BCG group was 0.62 versus 1.63 in the control group. Subgroup analysis showed significant benefit of BCG for patients with single as well as multiple, stages Ta and T1, and grades II and III tumors. Comparison with pretreatment controls in the BCG group revealed a significant reduction in the recurrence rate in those patients after treatment with BCG, which was not seen in the control group. The benefit of BCG was seen in those who received BCG initially as well as in those who received it after failure of intravesical chemotherapy. Multivariate analysis of prognostic factors showed that this benefit in the BCG group was related only to the treatment, while other prognostic parameters, such as tumor stage, grade, number and so forth were not independent prognostic variables. The rate of progression to muscle invasion was not significantly different in the 2 treatment groups. The relapse-free survival in the BCG group was 35.4% at 60 months compared to 11.2% in the control group (p < 0.001). The side effects of BCG therapy were mild, brief and easily controlled with conservative measures.