Treatment of patients with transitional cell carcinoma of the urinary bladder with intravesical poly I: poly C effects on natural killer function.

Considerable interest has been focused on the use of interferon (IFN) and IFN-inducers as antineoplastic agents in humans. The current report will focus on the effect of intravesical administration of Poly I: Poly C on NK activity in patients with TCC of the urinary bladder. NK cytotoxicity was measured in 14 patients with primary TCC, 8 patients received Poly I: Poly C and 5 other patients received intravesical thiotepa. Blood samples were obtained prior to and 48 h following each drug treatment. A variation in the initial NK level determined prior to treatment was observed in the different TCC patients: 5 patients treated with Poly I: Poly C and 5 patients treated with thiotepa exhibited low NK activity prior to treatment, whereas the other 3 patients who were treated with Poly I: Poly C had high initial NK levels. Following drug treatment it was shown that a significant elevation in the NK cytotoxicity was only observed in patients treated by intravesical Poly I: Poly C who had low NK activity prior to treatment. No such effect was observed in patients treated with thiotepa or in patients treated with Poly I: Poly C who exhibited a high NK activity prior to treatment.