PRIOR CONCURRENT THERAPY: Must have recovered from all acute toxic effects Biologic therapy: No concurrent biologic therapy At least 6 weeks since biologic therapy No concurrent immunotherapy No more than 1 prior biologic regimen Chemotherapy: No concurrent chemotherapy At least 6 weeks since chemotherapy No more than 1 prior chemotherapy regimen Endocrine therapy: At least 6 weeks since steroid therapy Radiotherapy: No concurrent radiotherapy At least 12 weeks since therapy including Sr 89 At least 6 weeks since other radiotherapy No prior cranial radiotherapy Surgery: Not specified Other: No concurrent immunosuppressives such as azathioprine or cyclosporine