PATIENT CHARACTERISTICS: Age: 18 and over Performance status: ECOG 0-2 Life expectancy: Not specified Hematopoietic: Granulocyte count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than upper limit of normal (ULN) AST and ALT no greater than 2.5 times ULN (no greater than 5 times ULN for liver metastases) Renal: Creatinine no greater than upper limit of normal Cardiovascular: Not specified Pulmonary: Not specified Other: No prior malignancy within past 5 years except curatively treated basal or squamous cell skin cancer or carcinoma in situ of the cervix Not pregnant or nursing Fertile patients must use effective contraception No active or uncontrolled infection No other serious illness or medical condition No known hypersensitivity to systemic liposomal formulation or any drug chemically related to study drug