PRIOR CONCURRENT THERAPY: Biologic therapy: No prior trastuzumab (Herceptin) No concurrent hematopoietic growth factors Chemotherapy: No prior chemotherapy for metastatic disease Prior adjuvant chemotherapy allowed (including regimens containing doxorubicin) No prior paclitaxel, 24 hour infusion fluorouracil, or capecitabine Endocrine therapy: Not specified Radiotherapy: No prior radiotherapy to 50% or more of the bone marrow Surgery: Not specified Other: No other concurrent experimental drugs