Intravesical thiotepa prophylaxis of superficial bladder cancer. A follow-up study.

Prophylactic intravesical instillations of thiotepa at 3-month intervals reduced the frequency of recurrences of superficial bladder tumors when compared with an untreated control group. Patients who developed frequent recurrences despite thiotepa instillations had a high risk of disease progression. These patients with progressive bladder carcinoma appeared to be unaffected by intravesical thiotepa in the dosage used. This raises the question as to whether such intravesical chemotherapy does anything to alter the underlying malignant process in the urothelium.