Radiation Therapy, Palbociclib, and Hormone Therapy in Treating Breast Cancer Patients With Bone Metastasis

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. 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. Antihormone therapy, such as fulvestrant, letrozole, anastrozole, exemestane, or tamoxifen, may lessen the amount of estrogen made by the body. Giving radiation therapy, palbociclib, and hormone therapy may work better in treating breast cancer patients with bone metastasis.