Summary
This phase II trial studies how well radiation therapy given with standard care palbociclib and hormone therapy work in treating patients with breast cancer that has spread from one part of the body to the bone (bone metastasis). Radiation therapy uses high energy x-rays to kill tumor cells and shrink tumors. Palbociclib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Estrogen can cause the growth of breast cancer cells. Letrozole, anastrozole, and exemestane lowers the amount of estrogen made by the body. This may help stop the growth of tumor cells that need estrogen to grow. Fulvestrant and tamoxifen blocks the use of estrogen by the tumor cells. Giving radiation therapy, palbociclib, and hormone therapy may work better in treating breast cancer patients with bone metastasis.