RATIONALE : Laboratory-treated T cells may stimulate the immune system in different ways and stop tumor cells from growing. Drugs used in chemotherapy, such as cyclophosphamide, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Vaccines made from HER2 peptides may help the body build an effective immune response to kill tumor cells that express HER2. Giving laboratory-treated T cells and cyclophosphamide after vaccine therapy may be an effective treatment for breast cancer.