A Study of Herceptin (Trastuzumab)and Biomarkers in Patients With HER2-Positive Metastatic Breast Cancer

A Prospective Study to Evaluate Alterations in Molecular Biomarkers in HER2 Neu Positive Metastatic Breast Cancer Together With Assessment of Trastuzumab Use Beyond Progression After Initial Response to Trastuzumab-taxane Based Treatment

This single arm study will evaluate alterations in molecular marker expression in HER2-positive targeted therapy, and will evaluate the effect of continued treatment with Herceptin and Xeloda beyond progression following initial Herceptin-taxane chemotherapy. Patients who develop progressive disease will receive first-line Herceptin (8mg/kg iv loading dose and 6mg/kg iv every 3 weeks) + taxane therapy. patients who develop progressive disease within 9 weeks of treatment will continue treatment with Herceptin in combination with Xeloda (1000mg/m2 po bid on days 1-14 of each 3-week cycle).Biopsies of tumor tissue will be taken for biomarker and gene profiling evaluation. The anticipated time on study treatment is until disease progression, intolerable side effects or patient choice, and the target sample size is 100 individuals.

Inclusion Criteria:

• female patients, >=18 years of age;
• HER2-positive breast cancer;
• al least one metastatic site amenable for core biopsy;
• left ventricular ejection fraction >50%.

Exclusion Criteria:

• prior adjuvant/neoadjuvant Herceptin within past 6 months;
• prior adjuvant taxane therapy within past 12 months;
• use of chemotherapy, immunotherapy or biological anticancer therapy within past 3 weeks;
• known bleeding diatheses.