Administration of stereotactic ablative body radiotherapy to oligoprogressive lesions delayed a change in systemic therapy in patients with estrogen receptor–positive/HER2-negative breast cancer enrolled to the prospective phase 2 AVATAR trial.
The National Comprehensive Cancer Network Guidelines now recommend the use of 18F-Fluorestradiol positron emission tomography in certain circumstances during the systemic staging workup for patients with recurrent or metastatic for estrogen receptor–positive breast cancer.