Lapatinib and Tamoxifen in Treating Patients With Locally Advanced or Metastatic Breast Cancer That Did Not Respond to Previous Tamoxifen

Inclusion Criteria: * Primary adenocarcinoma of the breast confirmed by histology or cytology * Locally advanced or metastatic disease not amenable to surgery or radiation therapy with curative intent * Estrogen and/or progesterone receptor positive cancer * Patients have failed hormonal manipulation with tamoxifen, either showing no response (primary resistance) to initial therapy or relapse/progression after showing initial response (secondary failure) * At least 1 measurable (target) lesion (i.e. any malignant tumor mass that can be accurately measured in at least 1 dimension, \>= 20 mm with conventional radiographic techniques or \>= 10 mm with magnetic resonance imaging \[MRI\] or spiral computerized tomography \[CT\] scans), in a previously un-irradiated area * No more than 450 mg/m\^2 of prior doxorubicin * Life expectancy \>= 3 months * Eastern Cooperative Oncology Group (ECOG) performance status =\< 2 (Karnofsky \>= 60%) * Absolute neutrophil count (ANC) \>= 1500/mm\^3 * Platelets \>= 100,000/mm\^3 * Hemoglobin \>= 9.0 g/dL * Creatinine (Cr) =\< upper limit of normal (ULN) or Cr clearance \> 60 mL/min/m\^2 * Total bilirubin =\< 1.5 x ULN * Alanine aminotransferase (ALT) =\< 1.5 x ULN or =\< 3 x ULN with liver metastases * Aspartate aminotransferase (AST) =\< 5 x ULN or =\< 3 x ULN with liver metastases * Cardiac ejection fraction within the institutional range of normal as measured by echocardiogram or multi gated acquisition scan (MUGA) scan; (note that baseline an…