OUTLINE: Induction: On day 0, patients receive cyclophosphamide IV over 30 minutes, doxorubicin IV over 15-30 minutes, etoposide IV over 1 hour, oral prednisone every 12 hours, and oral procarbazine. On days 1 and 2, patients receive etoposide IV over 1 hour, oral prednisone every 12 hours, and oral procarbazine. On days 3-6, patients receive oral prednisone every 12 hours and oral procarbazine. On day 7, patients receive vincristine IV, bleomycin IV over 5 minutes, and oral prednisone every 12 hours. On days 8-13, patients receive oral prednisone every 12 hours. Beginning on day 8, patients receive filgrastim (G-CSF) subcutaneously until absolute neutrophil counts recover. Treatment repeats every 3 weeks for 4 courses in the absence of disease progression or unacceptable toxicity. Consolidation therapy begins on week 12 or when blood counts recover. Consolidation for rapid early responders (patients with complete response (CR) or rapid early partial response (PR-1) to induction therapy): Females - Patients receive vincristine IV, cyclophosphamide IV over 30 minutes, oral prednisone every 12 hours, and oral procarbazine on day 0. On days 1-6, patients receive oral prednisone every 12 hours and oral procarbazine. On day 7, patients receive vinblastine IV, bleomycin IV over 5 minutes, doxorubicin IV over 15-30 minutes, and oral prednisone every 12 hours. On days 8-13, patients receive oral prednisone every 12 hours. Treatment repeats every 28 days for a total of 4 courses in the absence of disease progression or unacceptable toxicity. Males - Patients receive doxorubicin IV over 15-30 minutes, bleomycin IV over 5 minutes, vinblastine IV, and dacarbazine IV on days 0 and 14. Treatment repeats every 28 days for a total of 2 courses in the absence of disease progression or unacceptable toxicity. Beginning 3 weeks after completion of chemotherapy, male patients with CR or PR-1 receive radiotherapy 5 days per week to areas of initial disease involvement (total duration of radiotherapy is dependent on initial extent of disease). Consolidation for slow early responders: Patients with slow partial response (PR-2) or stable disease (SD) after 4 courses of induction therapy receive 4 additional courses of induction therapy in the absence of disease progression or unacceptable toxicity. Beginning on day 8, patients receive G-CSF subcutaneously until blood counts recover. Patients should be off G-CSF for more than 24 hours prior to the next course of chemotherapy. Beginning 3 weeks after completion of chemotherapy, male and female patients with PR-2 or SD receive radiotherapy 5 days per week to areas of initial disease involvement (total duration of radiotherapy is dependent on initial extent of disease). Patients are followed every 3 months for 2 years, every 6 months for 1 year, annually for 2 years and then at years 10 and 20.