PRIOR CONCURRENT THERAPY: Biologic therapy: No prior immunotherapy or biologic therapy for recurrent or metastatic disease No concurrent biologic therapy No concurrent filgrastim (G-CSF) as primary prophylaxis Chemotherapy: Prior adjuvant chemotherapy after complete resection of original tumor allowed Prior neoadjuvant chemotherapy allowed No prior chemotherapy for recurrent or metastatic disease No other concurrent chemotherapy Endocrine therapy: Not specified Radiotherapy: Prior adjuvant radiotherapy after complete resection of original tumor allowed Prior neoadjuvant radiotherapy allowed At least 4 weeks since prior radiotherapy No prior radiotherapy for recurrent or metastatic disease No prior radiotherapy to more than 25% of bone marrow No concurrent radiotherapy except to CNS Surgery: See Disease Characteristics Prior surgical resection of primary tumor allowed At least 4 weeks since prior abdominal exploration with resection (3 weeks without resection)