OUTLINE: Study randomized for adjuvant radiotherapy. All patients receive Induction chemotherapy on Regimen A, following which those in CR are randomized on Arms I and II. Regimen A: 7-Drug Combination Chemotherapy. MOPP/ABV Hybrid. Mechlorethamine, NM, NSC-762; Vincristine, VCR, NSC-67574; Procarbazine, PCB, NSC-77213; Prednisone, PRED, NSC-10023; Doxorubicin, DOX, NSC-123127; Bleomycin, BLEO, NSC-125066; Vinblastine, VBL, NSC-49842. Arm I: Radiotherapy. Involved-field irradiation using megavoltage equipment. Arm II: No further therapy.