PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: See Disease Characteristics Prior nitrosourea allowed if cumulative dose no more than 600 mg/m2 Prior bleomycin allowed if cumulative dose no more than 300 units/m2 Prior doxorubicin allowed if cumulative dose no more than 450 mg/m2 No prior high-dose etoposide (more than 1,800 mg/m2) No prior high-dose cyclophosphamide (more than 100 mg/kg) No chemotherapy within 4 weeks (no melphalan, nitrosourea, or mitomycin within 6 weeks) prior to bone marrow collection No prior salvage therapy Endocrine therapy: Not specified Radiotherapy: See Disease Characteristics No prior radiotherapy to liver or lung Prior other radiotherapy allowed if doses do not exceed the following limits: 1,400 cGy to the mediastinum 1,400 cGy to the whole abdomen 4,000 cGy to the CNS Surgery: Not specified