This phase II trial studies F-18 16 alpha-fluoroestradiol (FES) positron emission tomography (PET)/computed tomography (CT) in predicting response to endocrine therapy in patients with newly diagnosed breast cancer that has spread to other parts of the body. FES is a radioactive form of the hormone estrogen and may “light up” where cancer is in the body. Diagnostic procedures using FES, such as FES PET/CT, may help measure the FES and help doctors predict how well the cancer will respond to treatment.
NCT02398773 (clinicaltrials.gov)