FES Imaging to Optimize Tamoxifen for Metastatic Breast Cancer
Status:
Recruiting
Trial end date:
2023-12-01
Target enrollment:
Participant gender:
Summary
Despite broad advancements in endocrine therapy for ERα+ breast cancer, resistance ultimately
develops. A common driver of resistance are known ESR1 mutations that lead to constitutively
active receptor signaling and transcriptional regulation that is always "turned on" despite
the absence of estrogen. Patients with ESR1 mutations are expected to have decreased binding
affinity for tamoxifen and thus may be underdosed on standard therapy. [18F]-fluoroestradiol
Positron Emission Tomography/Computed tomography (FES-PET/CT) imaging is a novel functional
imaging technique that can non-invasively measure ERα expression and inhibition in metastatic
ERα+ breast cancer. The proposed a pilot study uses FES-PET/CT imaging to measure ERα
blockade to determine the optimal dose of tamoxifen in patients with ESR1 mutations.