PRIOR CONCURRENT THERAPY: Biologic therapy: No prior bone marrow transplantation with high-dose chemotherapy or radiolabeled monoclonal antibody therapy for lymphoma patients Chemotherapy: At least 4 weeks since prior chemotherapy (6 weeks since nitrosoureas) Endocrine therapy: See Disease Characteristics Radiotherapy: At least 4 weeks since prior radiotherapy Surgery: At least 2 weeks since prior major surgery Other: See Disease Characteristics No concurrent antiretroviral therapy