Capecitabine, Oxaliplatin and Trastuzumab in Treating Patients With HER2 Positive Metastatic Breast Cancer

Inclusion Criteria: Histologic or cytologic diagnosis of breast cancer with evidence of (1) unresectable, locally recurrent, or (2) metastatic disease.· HER2 gene amplification by FISH. HER protein overexpression by immunohistochemistry will not be sufficient for entry.· At least one measurable lesion as defined by the RECIST. Prior hormonal therapy for metastatic disease is allowed. Maximum of one prior chemotherapy regimen or trastuzumab-containing regimen for unresectable, locally recurrent or metastatic disease Prior radiation therapy is allowed as long as the irradiated area is not the only source of measurable disease. Exclusion Criteria: No prior therapy with capecitabine or oxaliplatin in any setting No prior therapy with other platinum compounds· No other forms of cancer therapy including radiation, chemotherapy and hormonal therapy within 21 days prior to beginning protocol therapy.· No prior unanticipated severe reaction to fluoropyrimidine therapy, or known sensitivity to 5-fluorouracil.· No prior fluoropyrimidine therapy for metastatic disease is allowed. Prior adjuvant fluoropyrimidine therapy is allowed if completed > 12 months from study entry.· No symptomatic brain metastasis. · No evidence of serious concomitant systemic disorders incompatible with the study · No peripheral neuropathy · No major surgery within 28 days prior to beginning protocol therapy.· Negative pregnancy test· No current breastfeeding· No malabsorption syndrome· No evidence of serious concomitant systemic disorders incompatible with the study· Patients must not be treated with any of the following while on protocol therapy or within 28 days prior to beginning protocol therapy: sorivudine, brivudine, cimetidine, allopurinol.