PRIOR CONCURRENT THERAPY: Biologic therapy: No more than 1 prior biologic therapy No concurrent biologic therapy No concurrent growth factors (e.g., epoetin alfa) Chemotherapy: No more than 1 prior chemotherapy regimen No other concurrent chemotherapy Endocrine therapy: Must be on stable dose of steroids for at least 1 week prior to study Concurrent steroids allowed Radiotherapy: See Disease Characteristics No concurrent radiotherapy Surgery: At least 2 weeks since prior surgical resection (newly diagnosed patients must be enrolled within 28 days of surgery or biopsy) Recovered from prior major surgery Other: No other concurrent investigational drugs