Interleukin-7 in Treating Patients With Refractory Solid Tumors

DISEASE CHARACTERISTICS: * Histologically confirmed malignancy meeting both of the following criteria: * No known curative therapy * Failed standard therapy, defined as either lack of response OR disease progression (i.e., at least 25% increase in disease or new disease) * Measurable or evaluable disease * No hematopoietic malignancies * No primary carcinoma of the lung PATIENT CHARACTERISTICS: Age * 18 and over Performance status * Karnofsky 80-100% Life expectancy * At least 3 months Hematopoietic * Absolute neutrophil count greater than 1,000/mm\^3 * Platelet count greater than 100,000/mm\^3 * No proliferative hematologic disease Hepatic * AST and ALT less than 3 times upper limit of normal (ULN) * PT/PTT no greater than 1.5 times ULN * No documented hepatitis B infection * No documented hepatitis C infection Renal * Creatinine clearance greater than 60 mL/min Cardiovascular * Ejection fraction greater than 45% by MUGA * Hypertension (resting blood pressure greater than 140/90 mm Hg) must be controlled with standard anti-hypertensive therapy Pulmonary * No severe asthma * DLCO/VA greater than 50% of predicted * FEV\_1 greater than 50% of predicted Immunologic * No autoimmune disease * Peripheral CD3+ cell count greater than 300/mm\^3 and stable on 4 successive determinations * HIV negative Other * Not pregnant * Negative pregnancy test * Fertile patients must use effective contraception * No other medical or psychiatric condition that would preclude study compliance * No cognitive impairment or likelihood of developing cognitive impairment during study participation * No need for palliative therapy * No splenomegaly PRIOR CONCURRENT THERAPY: Biologic therapy * More than 4 weeks since prior immunotherapy by cytokines, anti-tumor vaccines, or monoclonal antibody therapy prior to the initiation of peripheral CD3 count determination * No prior allogeneic hematopoietic stem cell transplantation * No other concurrent immunotherapy * No other concurrent biologic agents (e.g., growth factors or monoclonal antibodies) Chemotherapy * No concurrent chemotherapy Endocrine therapy * No prior systemic corticosteroid therapy for more than 72 hours within the 2 weeks prior to initiation of peripheral CD3 cell count determination * No concurrent chronic steroid therapy Radiotherapy * Not specified Surgery * No prior solid organ transplantation * No prior splenectomy Other * More than 4 weeks since prior cytotoxic therapy prior to the initiation of peripheral CD3 cell count determination * No concurrent cytotoxic therapy * No concurrent immunosuppressive therapy * No concurrent medications for the treatment of hypertension * No concurrent chronic asthma medications * No concurrent chronic anticoagulants (e.g., high-dose warfarin, heparin, or aspirin) * Low-dose oral warfarin allowed