Negative 18F-FES PET/CT Despite Estrogen Receptor Positivity by Immunohistochemistry
Immunohistochemistry (IHC) is routinely used to determine the estrogen receptor (ER) expression status of breast cancer. 18 F-fluoro-estradiol ( 18 F-FES) PET/CT is indicated for select breast cancer patients with ER+ breast cancer, and patients with tracer-avid disease typically enjoy favorable responses to endocrine therapy (ET). We present 2 patients with metastatic breast cancer that were ER+ on IHC but lacked tracer avidity on 18 F-FES PET/CT. We hypothesize that despite ER detection on IHC, these receptors were nonfunctional, lacking the ability to bind estrogen. Since functional ER is a prerequisite for response to ET, these patients are not likely to respond to ET.
Authors
- Mylin A. Torres (ORCID: https://orcid.org/0000-0003-3582-5216)
- David M. Schuster (ORCID: https://orcid.org/0000-0003-3077-742X)
- Elizabeth Sakach (ORCID: https://orcid.org/0000-0002-3295-0612)
- Ismaheel O. Lawal (ORCID: https://orcid.org/0000-0003-4273-040X)
- Yoram Baum
- David A. Mankoff (ORCID: https://orcid.org/0000-0002-6971-5413)
- Clara R. Farley
- Jane Meisel (ORCID: https://orcid.org/0000-0002-2642-865X)
- Qun Wang (ORCID: https://orcid.org/0000-0001-7929-7692)
- Xiaoxian Li (ORCID: https://orcid.org/0000-0002-0995-1721)
- Kunal Chaudhary (ORCID: https://orcid.org/0000-0002-8255-3551)
Institutions
- Emory University (US)
- University of Pennsylvania (US)
Publication Details
- Journal
- Clinical Nuclear Medicine
- Published
- 2025-06-06
- DOI
- https://doi.org/10.1097/rlu.0000000000006023
- Citations
- 1
- Primary Topic
- Medical Imaging Techniques and Applications
- Type
- article
- Field-Weighted Citation Impact
- 1.36