DISEASE CHARACTERISTICS: Histologic or cytologic confirmation of malignant solid tumor including, but not limited to: Breast cancer Prostate cancer Colon cancer Adrenocortical tumors No CNS metastases No conventional therapy for cure or palliation available

PATIENT CHARACTERISTICS: Age: 18 and over Performance status: ECOG 0-2 Life expectancy: At least 12 weeks Hematopoietic: Absolute neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: aPTT and PT no greater than upper limit of normal (ULN) Bilirubin no greater than 1.5 times ULN AST no greater than 2 times ULN Albumin at least 3.0 g/dL Renal: Creatinine clearance at least 50 mL/min Sodium and potassium normal Cardiovascular: Ejection fraction normal if prior doxorubicin therapy No New York Heart Association class III or IV heart disease No history of significant cardiac arrhythmia No history of congestive heart failure Neurologic: No seizure disorder No grade 2 or greater peripheral neuropathy Other: Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception No insulin-dependent diabetes mellitus No uncontrolled infection No chronic debilitating disease

PRIOR CONCURRENT THERAPY: Biologic therapy: At least 4 weeks since prior biologic therapy or immunotherapy No concurrent immunotherapy No concurrent filgrastim (G-CSF) or sargramostim (GM-CSF) Chemotherapy: More than 4 weeks since prior chemotherapy (6 weeks for mitomycin or nitrosoureas) and recovered Prior doxorubicin allowed if total dose less than 300 mg/m2 No other concurrent chemotherapy No more than 2 prior chemotherapy regimens for metastatic disease Endocrine therapy: No current steroid use of greater than 1.5 mg dexamethasone (or equivalent) per day Radiotherapy: At least 4 weeks since prior radiation therapy No radiation therapy to greater than 25% of bone marrow No concurrent radiotherapy Surgery: At least 4 weeks since prior major surgery