PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: No prior chemotherapy for advanced disease At least 1 year since prior adjuvant chemotherapy Endocrine therapy: At least 4 weeks since prior estrogens, androgens, and progestins Tamoxifen or aminoglutethimide allowed with no waiting period if disease progresses Recovery from prior hormonal therapy for metastatic disease required Radiotherapy: Prior radiotherapy allowed provided: Evaluable disease exists outside of treatment field No greater than 50% of bone marrow was irradiated Surgery: Not specified