Statement: Mark has HER2 positive breast cancer, he is eligible for the primary trial.
Primary_evidence: Inclusion Criteria:   Women aged > 18 years   Histologically documents metastatic breast cancer   HER2 positive using Fluorescence In Situ Hybridization (FISH)   For phase I, patients who have previously received treatment for their metastatic disease are allowed to participate.   For the phase II portion of the study, patients must have measureable disease (> 2 cm; > 1 cm on spiral CT scan)   Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2   A life expectancy of > 3 months   Use of effective means of contraception Exclusion Criteria:   For Phase II, prior cytotoxic chemotherapy and/or prior Herceptin for their metastatic disease. Prior treatment in the adjuvant setting is allowed.