DISEASE CHARACTERISTICS: Histologically proven solid tumor that is refractory to standard therapy or for which no standard therapy exists Eligible tumors, include, but are not limited to, the following: Breast Ovarian Head and neck Non-small cell lung cancer Abnormal liver function Control patients with normal liver function are enrolled Brain metastases allowed if controlled by radiotherapy or surgery and neurologic status currently stable Hormone receptor status: Not specified

PATIENT CHARACTERISTICS: Age: 18 and over Sex: Not specified Menopausal status: Not specified Performance status: Karnofsky 50-100% Life expectancy: At least 1 month Hematopoietic: Neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hemoglobin at least 9 g/dL OR Hematocrit at least 35% Hepatic: See Disease Characteristics No active acute hepatitis Renal: Creatinine no greater than 1.5 mg/dL OR Creatinine clearance at least 60 mL/min Cardiovascular: No concurrent cardiovascular disease that is poorly controlled with currently available treatment or of such severity as to preclude study Pulmonary: No concurrent pulmonary disease that is poorly controlled with currently available treatment or of such severity as to preclude study Other: No other concurrent illness (e.g., CNS disease) that is poorly controlled with currently available treatment or of such severity as to preclude study No severe infection requiring treatment Not pregnant Negative pregnancy test Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY: Biologic therapy: No prior bone marrow transplantation Chemotherapy: At least 4 weeks since prior chemotherapy (6 weeks for mitomycin or nitrosoureas) and recovered Endocrine therapy: Not specified Radiotherapy: See Disease Characteristics At least 4 weeks since prior radiotherapy and recovered No prior radiotherapy to more than 25% of bone marrow Surgery: See Disease Characteristics Recovered from major surgery