I. Determine the maximum tolerated dose of tipifarnib when administered with doxorubicin and cyclophosphamide in women with metastatic breast cancer (non-regional stage IV disease). (Phase I closed to accrual as of 1/19/04) II. Determine the pathologic complete remission rate in patients with locally advanced breast cancer (stages IIB, IIIA, IIIB, or IIIC) treated with the recommended phase II dose of this regimen.