This study tests whether an imaging method called Fluorodeoxyglucose (FDG) Positron Emission Tomography (PET/CT) – FDG PET/CT – can visualize and measure response to hormone therapy for women with breast cancer that has spread, or metastasized, to the bone. If successful, this trial may offer an improved way to assess whether bone metastases are responding to treatment and to inform treatment decisions.