The Diagnostic Accuracy of F-FDG PET and F-FES PET for Staging Grade 1-2 Estrogen Receptor-Positive Breast Cancer.

Background According to current guidelines, staging of patients with locally advanced breast cancer and local-regional recurrent breast cancer is preferably performed with PET using 2-fluorine 18-fluoro-2-deoxy-d-glucose (F-FDG). However, F-FDG PET might underperform in low-grade estrogen receptor (ER)-positive breast cancer. Alternatively, 16α-F-fluoro-17β-estradiol (F-FES) has emerged as a powerful tracer for in vivo visualization of ER-positive lesions.