Response of nude mouse-grown human urothelial cancer to cis-diamminedichloroplatinum(II), diammine[1,1-cyclobutanedicarboxylato(2-)-O,O'-platinum], and mitoguazone dihydrochloride.

A comparative study of the effect of cis-diamminedichloroplatinum(II) (cisplatin), diammine[1,1-cyclobutanedicarboxylato(2-)-O,O'-platinum] (carboplatin), and mitoguazone dihydrochloride on urothelial cancer was conducted using transitional cell carcinomas of the urinary bladder grown in the nude mouse. Tumors SW-780 and TCC-K1 represented transitional cell carcinoma, Grade II, whereas Tumor PR49 represented a fast-growing Grade III neoplasm. Of the agents studied, cisplatin was most effective, resulting in tumor response related to the dose administered. Response to carboplatin was clearly related to treatment schedule. For the same amount of total dose administered, better results were obtained when treatment was given three times weekly instead of once every week. Furthermore, cisplatin was more effective against the less differentiated PR49 tumor in contrast to carboplatin, which showed more activity against the better differentiated SW-780 and TCC-K1 tumors. None of the tumors tested responded to mitoguazone dihydrochloride. The results of the present study may assist in formulating better treatment modalities against urothelial cancer, taking into account factors such as tumor grade, growth rate, treatment schedule, and the patient's tolerance which may ultimately influence tumor response.