Activity of standard and investigational cytotoxic drugs in primary cultures of tumor cells from patients with kidney and urinary bladder carcinomas

Randomized Phase II marker lesion study evaluating effect of scheduling on response to intravesical gemcitabine in recurrent Stage Ta urothelial cell carcinoma of the bladder

OBJECTIVES

To evaluate the response rate for intravesical gemcitabine given in three different schedules to patients with recurrent multiple carcinoma of the urinary bladder Stage Ta, grade 1-2, in whom all but one marker lesion was removed. Furthermore, we sought to define the safety profile.

METHODS

This was a multicenter, open-label, randomized, Phase II study in which gemcitabine 2000 mg in 100 mL of unbuffered saline was instilled as a single dose (n = 11), two doses per week for 3 weeks (n = 11), or once weekly for 6 weeks (n = 10). Efficacy was evaluated using cystoscopy after 9 weeks. Toxicity was evaluated by assessing the liver, kidney, bone marrow, and coagulation function at defined intervals and by questionnaire.

RESULTS

A total of 32 patients were included, 2 of whom were subsequently excluded because of protocol violations. The overall complete remission rate was 31%. The respective subgroup response rate was 10% in the single-dose group, 44% in the once-weekly group, and 40% in the twice-weekly group. The most common side effect was nausea. One patient withdrew because of nausea and fever, and an additional 2 patients had reversible hematologic toxicity (mild thrombocytopenia causing delayed instillation and mild anemia). The side effects were generally in the multiple-dose groups, with an overrepresentation in women. Ten patients were unable to retain the drug intravesically for the full hour.

CONCLUSIONS

The results of our study have shown that gemcitabine has a tumor ablative effect when given intravesically for bladder cancer. A single dose seemed ineffective, and the multiple dosing regimens seemed effective. The side effects were generally mild.

Intravesical therapy of superficial bladder cancer

The aim of treatment of superficial bladder cancer with intravesical therapy is threefold: (1) Eradicate existing disease. (2) Prevention of recurrence. (3) Prevention of tumor progression. The prognostic factors allow differentiation in different risk groups and this is useful in planning treatment. Studies on pharmacokinetics have proved the efficacy of optimized drug delivery. Comparing resection with and without intravesical chemotherapy a short term approximately 15% decrease in tumor recurrence with chemotherapy can be obtained but no effect on progression was proven. No agent has proved more effective than the other. Single, early instillation of chemotherapy has proven effective but the role of maintenance therapy has been controversial. Immunotherapy in the form of Bacillus Calmette-Guerin generally have proven more efficacious than chemotherapy. The results in comparison to mitomycin C have not been as conclusive. Several new approaches are explored to improve the efficacy of this therapy.

Management of superficial bladder cancer: what is new?

The management of superficial bladder cancer has not changed much during the last years. Transurethral resections with adjuvant intravesical instillation to risk groups have been standard therapy. Cystoscopy and cytology have been used for follow-up. Recently combinations of drugs for instillation and new urinary markers for diagnosis and follow-up have been tested. The role of these new modalities has not been easily judged. Thus the timely advent of guidelines with policy recommendations will play an important part in improving the care of patients in the future.