Prophylactic effect of triethylenethiophosphoramide on the recurrence rate of superficial bladder tumors.

The prophylactic effect of triethylenethiophosphoramide (thio-TEPA) on the recurrence rate of superficial transitional cell carcinoma of the bladder was examined in three groups of patients. Patients in group 1 had been treated by transurethral resection of the tumor before the study began; thereafter, topical thio-TEPA was added to the therapeutic regimen. The mean recurrence rate in this group dropped from 1 in 11.1 months before treatment with thio-TEPA to 1 in 28.6 months during treatment. Group 2 included patients treated by transurethral resection, with the addition of thio-TEPA instillation as soon as a diagnosis of transitional cell carcinoma of the bladder was established. In this group, the recurrence rate was 1 in 34.6 months. The control group for group 2 (group 3) was treated by transurethral resection of the tumor with no thio-TEPA instillation, and in this group, the recurrence rate was 1 in 11.6 months. These results justify the prophylactic use of thio-TEPA in patients with transitional cell carcinoma of the bladder.