Allogeneic Natural Killer (NK) Cells in Patients With Advanced Metastatic Breast Cancer

RATIONALE: Giving chemotherapy before a donor natural killer (NK) cell infusion helps stop the growth of tumor cells. It also helps stop the patient's immune system from rejecting the donor's cells. Giving NK cells from a related donor may kill the tumor cells. PURPOSE: This study furthers the research of previous studies (MT2003-01 and MT2004-25) which were to determine a specific preparatory regimen (cyclophosphamide and fludarabine) could create an environment in which infused NK cells can grow and effectively treat patients with relapsed AML. This study will test the previous regimen in patients with breast cancer.