Intravesical therapy for bladder cancer.

Bladder tumors confined to the mucosa and lamina propria are heterogeneous. Papillary, low-grade (I-II) noninvasive tumors (Ta) may recur frequently, thus subjecting the patient to numerous endoscopic procedures, but these patients infrequently have progression in grade or stage. Treatment need not be overly aggressive. High-grade (III) tumors confined to the mucosa (carcinoma in situ or Ta) or with lamina propria invasion (T1) require not only thorough initial endoscopic resection if possible, but extremely careful monitoring. Intravesical therapy should be seriously considered, as a subsequent tumor might invade the muscle and thus be life threatening. At this writing, there are no conclusive data to indicate which intravesical agent is most appropriate for each circumstance. Randomized trials are in progress. A few statements are possible, however. Thiotepa delays the development of low-grade tumors when used for prophylaxis. Toxicity is low, and the drug is not expensive. Mitomycin C is effective for treatment of residual superficial tumor and when instilled regularly after complete transurethral resection (prophylaxis). Side effects are infrequent (cystitis, dermatitis, rash) and almost never severe. The drug is expensive. Adriamycin appears to be active in the treatment and prophylaxis of superficial tumors, but its precise role has not been defined. Cystitis is common. BCG may be the most effective intravesical agent in the treatment of carcinoma in situ. The frequency and severity of local and systemic side effects vary with the strain but are potentially worse than with the chemotherapeutic agents. Thus, the clinician must carefully consider which patients to treat with BCG.