Lapatinib Recruiting Phase 2 Trials for Stage IV Breast Cancer / Stage IV Breast Cancer AJCC v6 and v7 / ERBB2 Gene Amplification / HER2 Positive Breast Carcinoma / Invasive Breast Carcinoma / Male Breast Carcinoma / HER2/Neu Positive / Recurrent Breast Carcinoma / Metastatic Malignant Neoplasm in the Brain Treatment