The purpose of this study is to determine the effectiveness and safety of administering Herceptin in combination with Taxol (paclitaxel) in the treatment of women with HER2-positive, early stage breast cancer prior to surgery.

Patients will receive Herceptin intravenously once weekly for 12 weeks, and Taxol intravenously every 3 weeks (week 1, week 4, week 7 and week 10).

After 12 weeks of treatment, breast surgery will be performed (either a lumpectomy or a mastectomy).

Once patients have recovered from the surgery, they will receive adriamycin and cytoxan every 3 weeks for 4 cycles (12 weeks total).

After Herceptin and Taxol therapy, tumor assessment will be performed along with an echocardiogram and mammogram.

At the time of surgery, re-assessment of the tumor will be done.

Blood work will be performed on day one of each chemotherapy cycle.

Inclusion Criteria:

• Patients must have Stage II or III histologically diagnosed breast cancer
• Primary invasive breast cancers that overexpress the HER2/neu oncogene
• Age older than 18 years
• Eastern Cooperative Oncology Group (ECOG) performance status of < 1
• White blood cell (WBC) > 4000/mm3
• Platelet count > 100,000/mm3
• Bilirubin < 1 x upper limit of normal (ULN)
• SGOT < 1 x ULN
• Creatinine < 1.5mg/dl
• Normal cardiac function and electrocardiogram (EKG) showing absence of ischemic changes or ventricular hypertrophy

Exclusion Criteria:

• Excisional biopsy, sentinel node dissection or axillary node dissection.
• Prior history of breast cancer unless: diagnosed at least 2 years ago, present cancer is not in a previously irradiated breast, no prior therapy with anthracycline or taxane, no prior high-dose chemotherapy with stem cell or bone marrow transplant.
• Pregnant or breast-feeding women
• Uncontrolled infection
• Active or severe cardiovascular or pulmonary disease
• Peripheral neuropathy of any etiology that exceeds grade 1
• Prior history of malignancy treated without curative intent
• Uncontrolled diabetes