Superficial Bladder Cancer Therapy: A Review

Abstract

Most bladder cancers present as a superficial disease, confined to the bladder mucosa or submucosal layer, without muscle invasion. Most superficial tumors have a propensity for recurrence after transurethral resection; some have a high risk for progression to muscle invasion. The treatment aim in superficial bladder cancer with intravesical therapy is three-fold: (1) eradicate existing disease, (2) prevention of recurrence, (3) prevention of tumor progression. The prognostic factors (tumor stage, grade, size, number and recurrence pattern) allow the stratification of tumors in different risk groups to plan treatment. Studies on pharmacokinetics have proved the efficacy of optimized drug delivery. Comparing resection with and without intravesical chemotherapy, a short-term reduction, approximately 15%, in tumor recurrence with chemotherapy can be obtained, but no effect on progression was proven. No agent has proved to be more effective than the others. A single instillation of chemotherapy immediately after transurethral resection has proven to be effective, but the role of maintenance therapy is controversial. Immunotherapy, in the form of Bacillus Calmette-Guerin, is generally shown to be more effective than chemotherapy, even if the results in comparison to mitomycin C do not result conclusive. Several new approaches are being explored to improve the efficacy of this therapy.