Single dose intravesical thiotepa as an adjuvant to cystodiathermy in the treatment of transitional cell bladder carcinoma.

Tumour cell implantation may be a factor in the aetiology of recurrent well-differentiated superficial bladder tumours. A prospective trial is reported in which single dose intravesical thiotepa was administered to a group of randomly selected patients immediately after cystodiathermy. A control group of patients was treated by cystodiathermy alone and tumour recurrence in the 2 groups was compared. Significantly fewer patients in the thiotepa-treated group developed recurrent tumour and there was also a significantly reduced incidence of pure vault recurrence in this group. The beneficial effects of adjuvant thiotepa were apparent after 1 treatment. In this series of patients no benefit resulted from the continued use of adjuvant thiotepa once a patient developed a recurrent tumor.