Arm II: Patients receive cyclophosphamide IV, doxorubicin IV, and vincristine IV on day 1 and oral prednisone on days 1-5. Treatment repeats every 3 weeks for a minimum of 4 courses or 2 courses beyond complete response. Patients with stage I, stage IE (including bulky), or nonbulky stage II or IIE disease receive 3 courses of chemotherapy. Patients receive radiotherapy beginning 3 weeks after completion of the third course of chemotherapy.