Clinical dilemmas in breast cancer patients resolved with a newly approved PET imaging agent
A non-invasive, patient-friendly imaging technique can help physicians make treatment decisions for breast cancer patients when diagnostic dilemmas arise. The 18F-FES PET – approved by the U.S. Food and Drug Administration in 2020 – solved 87% of dilemmas, providing doctors with information for personalized treatment decision-making. This research was published in the September issue of The Journal of Nuclear Medicine.
A key feature of breast cancer is the estrogen receptor (ER), which is expressed by 79 percent of breast tumors. Breast tumors that are ER-positive are likely to respond to hormone therapy. To assess the presence of ER, a biopsy of a tumor or metastasis is commonly done. However, clinical dilemmas can arise when a biopsy cannot be performed safely or when discrepancies in ER expression are suspected between tumor lesions.
18F-FES PET has the potential to visualize ER expression of all tumors in the body and could provide useful information regarding clinical dilemmas in breast cancer patients. In our study, we assessed whether the clinical dilemmas of ER could be resolved by 18F-FES PET results. “
Carolina P. Schröder, MD, PhD, medical oncologist, University Medical Center Groningen in the Netherlands
The retrospective study examined 100 18F-FES PET performed on 83 patients with three types of clinical dilemmas. These dilemmas included the inability to determine the extent of the disease with the standard workup, the unclear ER status of the tumor, or the inability to determine which primary tumor caused the metastases.
The clinical dilemma was resolved by 18F-FES PET in 87% of scans. In 93 percent of resolved cases, a treatment decision was based directly on the 18PET F-FES result. The frequency of the dilemmas resolved was not associated with the type of dilemma. However, the frequency of resolved dilemmas was related to RE status, as dilemmas in positive RE scans were more likely to be resolved than in negative RE scans.
“This is the largest study demonstrating the value of 18F-FES PET in “real daily clinical practice”, ”said Schröder. “These results support the use of 18F-FES PET for optimal patient outcomes and can support wide implementation of 18F-FES PET in clinical practice. “
Society of Nuclear Medicine and Molecular Imaging
Boers, J., et al. (2021) Value of 18F-FES PET in resolving clinical dilemmas in breast cancer patients: a retrospective study. Journal of Nuclear Medicine. doi.org/10.2967/jnumed.120.256826.