Letrozole and Celecoxib in Treating Postmenopausal Women With Locally Advanced or Metastatic Breast Cancer

RATIONALE: Estrogen can cause the growth of breast cancer cells. Hormone therapy using letrozole may fight breast cancer by lowering the amount of estrogen the body makes. Celecoxib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the tumor. Giving letrozole with celecoxib may kill more tumor cells. PURPOSE: This phase II trial is studying how well letrozole and celecoxib work in treating postmenopausal women with locally advanced or metastatic breast cancer.