PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: No prior chemotherapy for this disease within the past 5 years Endocrine therapy: Not specified Radiotherapy: At least 3 weeks since prior radiotherapy and recovered No prior radiotherapy to more than 25% of bone marrow No prior radiotherapy to measurable lesion unless documented progression after therapy No concurrent radiotherapy, including palliative radiotherapy Surgery: At least 3 weeks since prior major surgery