Methotrexate, Cisplatin, and Vinblastine (MCV) was followed by Cisplatin plus radiation therapy in 19 patients with muscle-invading clinical Stage T2-4NXM0 transitional cell carcinoma of the urinary bladder (including cystectomy candidates), to achieve local control and prevent distant metastases. Radical cystectomy was recommended for all patients who failed to reach a complete response (CR = biopsy negative and cytology not positive) following MCV and Cisplatin X 2 plus 4000 cGy. Completely responding patients, and those partially responding patients unsuited for cystectomy, were selected for bladder conservation treated with additional irradiation to the bladder tumor volume (total 6,480 cGy) plus one additional Cisplatin treatment. Dose reductions were required for stomatitis in 26%, mild bone marrow depression in 58%, and renal toxicity in 5% of the patients. During the Cisplatin/4000 cGy, mild dysuria occurred in 68% of patients and 36% had mild bowel hyperactivity. Serious complications have occurred in two patients to date. One patient had recurrent pulmonary emboli, marked reduction in bladder capacity, and diarrhea. A second had bladder perforation during cystoscopic evaluation after MCV and a small bowel obstruction after Cisplatin and 4000 cGy. There was no treatment-related sepsis. Three patients had initial complete transurethral resection of their tumors and therefore 16 patients are evaluable for tumor responsiveness to this protocol. Four patients (25%) were biopsy negative and cytology negative, whereas three additional patients (19%) were biopsy negative but cytology positive following initial MCV. Six patients (38%) were biopsy negative and cytology negative whereas three additional patients (19%) were biopsy negative and cytology positive following MCV and Cisplatin X 2 plus 4000 cGy pelvic radiation. Of the entire group, 9 patients were treated with full-dose radiotherapy. All of these patients are alive without evidence of tumor on rebiopsy of the original tumor site, but one has a persistent positive cytology. Seven patients had a radical cystectomy and 6 are disease free. The treatment of 3 patients deviated from the protocol. Overall, only one patient has developed distant metastases and currently 84% of the patients are disease-free, although follow-up is short. To date, this feasibility study has been clinically practical and well tolerated. The proportion of CR's suggests that this program may prove to be an organ-sparing and curative approach for a significant number of patients, but more experience and follow-up are required.