Radiation Therapy With or Without Chemotherapy in Treating Patients With Stage II or Stage III Bladder Cancer

RATIONALE: Radiation therapy uses high-energy x-rays to damage tumor cells. Drugs used in chemotherapy such as fluorouracil and mitomycin use different ways to stop tumor cells from dividing so they stop growing or die. Fluorouracil and mitomycin may make the tumor cells more sensitive to radiation therapy. It is not yet known if radiation therapy is more effective with or without chemotherapy in treating bladder cancer. PURPOSE: Randomized phase III trial to compare the effectiveness of radiation therapy to all or part of the bladder with or without chemotherapy in treating patients who have stage II or stage III bladder cancer.