Intravesical high dose 5-fluorouracil instillations combined with allopurinol--a therapeutic alternative in the treatment of multiple bladder tumors.

Chemical cystitis and systemic toxic effects limit the therapeutic use of intravesical cytotoxic agents against bladder tumors. In our series 1,000 mg. 5-fluorouracil could be instilled 2 hours daily, 5 days per week for 5 weeks if 100 mg. allopurinol were given 3 times daily simultaneously. After 6 weeks all patients were macroscopically free of tumors. Another instillation was performed because of recurrences within 6 months in 3 patients. This preliminary report of 5 patients with multiple superficial transitional cell bladder tumors shows that a combined treatment of high dose 5-fluorouracil instillation and simultaneous oral allopurinol will abolish temporarily all tumor tissue without signs of general absorption or chemical cystitis. The observation time is too short to predict definitive cure.