Intravesical thiotepa and mitomycin C treatment immediately after transurethral resection and later for superficial (stages Ta and Tis) bladder cancer: a prospective, randomized, stratified study with crossover design.

In a prospective, randomized, stratified study with crossover design the effect of thiotepa was compared to that of mitomycin C when each was instilled intravesically immediately at the end of complete removal of superficial bladder cancer (stages Ta and Tis) and later on tumor recurrence. The 3-month and 1-year rates free of recurrence were 93 and 78 per cent, respectively, for thiotepa (41 patients), and 97.6 and 67.1 per cent, respectively, for mitomycin C (42 patients) (p equals 0.6). On crossover (5 patients to thiotepa and 9 to mitomycin C) at 1 year 60 per cent of the patients receiving thiotepa secondarily and 51.9 per cent of those receiving mitomycin C secondarily were free of recurrence (p equals 0.52). Therefore, both drugs are equally effective in reducing bladder tumor recurrence. Future comparative studies should continue to include thiotepa as a standard by which the efficacies of other agents are judged.