Intralesional alpha interferon therapy in papillary superficial transitional cell carcinoma of the bladder. A pilot study.

The tolerability, toxicity and therapeutic efficacy of recombinant interferon alpha-2a (rIFN alpha-2a), administered by intralesional injection, were evaluated in 15 patients with papillary superficial transitional cell carcinoma of the bladder, rIFN alpha-2a was delivered endoscopically in a single weekly dose of 3 x 10(6) IU for 4 weeks (total 12 x 10(6) IU). Transurethral resection of residual tumours was then performed. The response to treatment was assessed according to ultrasonographic, endoscopic and pathological findings. One patient achieved complete remission, 6 partial remission, 6 minor remission and 2 stabilisation of disease. All patients completed the course of treatment. A mild, transient, flu-like syndrome was documented after every injection. Immunological findings suggest that the antitumour effects of rIFN alpha 2a are not mediated through the immune system.