After reviewing the data on intravesical
therapy for treatment or prophylaxis of urothelial
tumors of the bladder, several statements seem appropriate.
Bladder tumors confined to the mucosa and lamina propria represent a heterogeneous group. Papillary, grade I, noninvasive
tumors (Ta) may recur frequently, subjecting the patient to numerous endoscopic procedures but these patients very infrequently have
tumor progression. Treatment should not be overly aggressive and result in significant morbidity. These patients should be informed that they have a choice and may decide that they would rather take the risk of subsequent endoscopic procedures and avoid the regular visits to the office for intravesical
drug instillation. High grade
tumors, be they confined to the mucosa or invade the lamina propria, place the patient at significant risk of recurrence and local progression and thus require careful monitoring (Jordan et al, 1987; Torti et al, 1987). Intravesical
therapy should be seriously considered, either to eradicate residual malignant cells or prevent a subsequent
tumor.
Thiotepa is moderately effective in delaying the development of subsequent low grade
tumors when used for prophylaxis. Toxicity with
Thiotepa is low and the
drug is not expensive.
Mitomycin C is effective for the treatment of
residual tumor as well as when instilled regularly following complete transurethral resection. Side effects are primarily confined to chemical
cystitis with an occasional patient having a
rash. BCG may be the most effective intravesical agent in the treatment of
carcinoma in situ. Randomized trials comparing BCG and
chemotherapy are in progress and are eagerly awaited. The frequency and severity of local and systemic side effects are somewhat greater than with chemotherapeutic agents.