PRIOR CONCURRENT THERAPY: Biologic therapy: No concurrent immunological therapy Chemotherapy: At least 1 prior chemotherapy regimen for advanced disease (including adjuvant therapy), but not more than 2 prior regimens At least 4 weeks since prior chemotherapy (6 weeks for nitrosourea or mitomycin) and recovered Cumulative dose of prior epirubicin no greater than 450 mg/m2 Cumulative dose of prior doxorubicin no greater than 240 mg/m2 No concurrent chemotherapy Endocrine therapy: No concurrent hormonal therapy Low dose steroid therapy allowed if dose established at least 4 weeks prior to study Radiotherapy: At least 4 weeks since prior radiotherapy and recovered Surgery: Not specified Other: No concurrent experimental therapy