Treatment of Advanced Transitional Cell Carcinoma of the Bladder by Irinotecan in an Experimental Animal Model

Background and Aims: In advanced transitional cell cancer of the bladder a systemic chemotherapy isconsidered therapy of choice with palliative intent in spite of an unsatisfactory rate of remission. We tested a new chemotherapeutic agent, irinotecan, presenting with fair response rates in patients with advanced intestinal carcinomas, in animals with poorly differentiated transitional cell carcinomas (TCC). Methods: The effect of irinotecan was tested using single and multiple applications as well as in combination with docetaxel. Local tumor growth and body weight of mice were registered frequently. Histopathology of local tumor and previously defined organs were obtained after death. All data were proofed statistically. Results: The animal groups are statistically significant different for the tumor size (p < 0.01). Post-hoc tests showed that the control group and the irinotecan monotherapy (p = 0.04), as well as the irinotecan/docetaxel group (p < 0.01) are significant different for a reduced tumor mass. No significance could be detected for regression rate and survival time of the animals. Conclusions: The chemotherapy of irinotecan as monotherapy or in combination with docetaxel seems to be a promising alternative in the palliative treatment of advanced, metastatic transitional cell cancer of the bladder. Due to the significant influence of irinotecan on the reduction of tumor mass, we are planning a prospective randomised study to confirm these data in humans.