Cabergoline in Metastatic Breast Cancer

Inclusion Criteria: * Patients must have histologically confirmed metastatic breast cancer; tissue (a minimum of 3 slides) from the most recent biopsy is required for review and confirmation of eligibility; NOTE: material should ideally be from the metastatic disease, however material from the primary tumor is acceptable if that is all that is available * Patients must have stage IV breast cancer * Patients must have tumors (primary or metastatic) that stain positively for the prolactin receptor * Patients may have measurable or evaluable disease * Measurable disease is defined as at least one lesion that can be accurately measured in at least one dimension (longest diameter to be recorded) as \> 20 mm with conventional techniques or as \> 10 mm with spiral CT scan * Evaluable disease is disease that does not meet the criteria for measurable disease; examples would include patients with effusions or bone-only disease * Women of childbearing potential must commit to the use of effective barrier (non-hormonal) contraception while on study * Patients must have a life expectancy of greater than 12 weeks * Patients must have an Eastern Cooperative Oncology Group (ECOG) performance status =\< 2 * Patients may have had a prior diagnosis of cancer if it has been \> 5 years since their last treatment * Leukocytes \>= 3,000/uL (microliter) * Absolute neutrophil count \>= 1,500/uL * Platelets \>= 100,000/uL * Child Pugh score =\< 10 * Patients must be able to swallow and retain oral medication * All patients must have given signed, informed consent prior to registration on study Exclusion Criteria: * Women who are pregnant or lactating are not eligible for study treatment * Patients who are undergoing concomitant radiotherapy are NOT eligible for participation * Patients who are receiving any other investigational agents or concurrent anticancer therapy are NOT eligible for participation; previous systemic treatment is allowed with a 2 week washout period prior to registration * Patients who are taking any herbal (alternative) medicines are NOT eligible for participation; patients must be off any such medications by the time of registration * Patients who are receiving concomitant D2-antagonists (such as phenothiazines, butyrophenones, thioxanthenes, or metoclopramide) are NOT eligible for participation; patients must be off any such medications by the time of registration * Patients with known brain metastases are NOT eligible for participation * Patients with any of the following conditions or complications are NOT eligible for participation: * Uncontrolled hypertension * Known hypersensitivity to ergot derivatives * History of cardiac valvular disorders, as suggested by anatomical evidence of valvulopathy of any valve (to be determined by pre-treatment evaluation including echocardiographic demonstration of valve leaflet thickening, valve restriction, or mixed valve restriction-stenosis) * History of pulmonary, pericardial, cardiac valvular, or retroperitoneal fibrotic disorders * Gastrointestinal (GI) tract disease resulting in an inability to take oral medication * Malabsorption syndrome * Require intravenous (IV) alimentation * History of prior surgical procedures affecting absorption * Uncontrolled inflammatory GI disease (e.g., Crohn's, ulcerative colitis)