RATIONALE: Estrogen can cause the growth of breast cancer cells. Hormone therapy using fulvestrant and exemestane, anastrozole, or letrozole may fight breast cancer by blocking the use of estrogen by the tumor cells and by lowering the amount of estrogen the body makes. Lapatinib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. It is not yet known whether fulvestrant is more effective with or without lapatinib and/or aromatase inhibitor therapy in treating breast cancer.