According to the American Cancer Society, about two out of every three breast cancer cases are hormone receptor-positive. Most of these cases are estrogen receptor-positive (ER+), making this molecular subtype the most common type of breast cancer diagnosed today. The ER status in breast cancer is typically measured by immunohistochemistry (IHC) of fixed biopsy breast tissue. However, sampling error due to intratumoral heterogeneity1 presents a huge challenge in the overall tumor assessment. Non-invasive imaging plays a critical role to holistically characterize the whole tumor for more accurate diagnosis and staging.
Positron emission tomography (PET), in particular, offers a highly sensitive quantitative measure of molecular markers expressed in tumors. Estradiol, a form of estrogen, is produced for tissues of the reproductive organs, and 18F-fluoroestradiol ([18F]FES)…
