Combination radiotherapy and chemotherapy in murine bladder cancer.

A murine transitional cell carcinoma tumor model has been used to evaluate the combined use of radiotherapy and three chemotherapeutic agents, doxorubicin hydrochloride (Adriamycin), cyclophosphamide, and cis-diamminedichloroplatinum. The preliminary radiation therapy evaluation demonstrated that the tumor is radiosensitive. The combined use of cyclophosphamide and radiation therapy was the most effective regimen, especially when the drug was started prior to radiotherapy. Cis-diamminedichloroplatinum and radiation were a lethal combination, but a synergistic effect was produced when the drug was given after completion of radiotherapy. Doxorubicin hydrochloride and radiotherapy may be synergistic, but more evaluation is necessary.