DISEASE CHARACTERISTICS: Histologically proven soft tissue sarcoma, including the following cell types: Malignant fibrous histiocytoma Liposarcoma Rhabdomyosarcoma Synovial sarcoma Malignant paraganglioma Fibrosarcoma Leiomyosarcoma Angiosarcoma including hemangiopericytoma Neurogenic sarcoma Unclassified sarcoma Miscellaneous sarcoma including mixed mesodermal tumors of the uterus Cell types NOT allowed: Malignant mesothelioma Chondrosarcoma Neuroblastoma Osteosarcoma Ewing's sarcoma Embryonal rhabdomyosarcoma Measurable lesion with evidence of progression within 6 weeks prior to study (osseous lesions, hepatomegaly, lymphedema, ascites, and pleural lesions are not considered measurable) No symptomatic or known CNS metastases