Summary: Appropriate Use Criteria for Estrogen Receptor–Targeted PET Imaging with 16α-¹⁸F-Fluoro-17β-Fluoroestradiol

Abstract

PET imaging with 16a-18 F-fluoro-17b-fluoroestradiol ( 18 F-FES), a radiolabeled form of estradiol, allows whole-body, noninvasive evaluation of estrogen receptor (ER). 18 F-FES is approved by the U.S. Food and Drug Administration as a diagnostic agent "for the detection of ER-positive lesions as an adjunct to biopsy in patients with recurrent or metastatic breast cancer." The Society of Nuclear Medicine and Molecular Imaging (SNMMI) convened an expert work group to comprehensively review the published literature for 18 F-FES PET in patients with ER-positive breast cancer and to establish appropriate use criteria (AUC). The findings and discussions of the SNMMI 18 F-FES work group, including example clinical scenarios, were published in full in 2022 and are available at https://www.snmmi.org/auc. Of the clinical scenarios evaluated, the work group concluded that the most appropriate uses of 18 F-FES PET are to assess ER functionality when endocrine therapy is considered either at initial diagnosis of metastatic breast cancer or after progression of disease on endocrine therapy, the ER status of lesions that are difficult or dangerous to biopsy, and the ER status of lesions when other tests are inconclusive. These AUC are intended to enable appropriate clinical use of 18 F-FES PET, more efficient approval of FES use by payers, and promotion of investigation into areas requiring further research. This summary includes the rationale, methodology, and main findings of the work group and refers the reader to the complete AUC document.

Development of Radiopharmaceuticals for NPY Receptor-5 (Y5) Nuclear Imaging in Tumors by Synthesis of Specific Agonists and Investigation of Their Binding Mode

“…Imaging estrogen-receptor (ER) positive breast cancer with [ 18 F]-FDG can be challenging in low grade tumors . 16α-[ 18 F]­Fluoro-17β-estradiol ([ 18 F]­FES that binds to ER) is nowadays approved for the detection of ER-positive lesions as an adjunct to biopsy with recurrent or metastatic breast cancer to support treatment decision-making . However, the primary consideration for [ 18 F]-FES PET imaging is washout of prior ER antagonist to prevent false negative imaging .…”

The Role of Molecular Imaging in Patients with Brain Metastases: A Literature Review

“…Recently, 16-alpha- 18 F-fluoro-17-beta-estradiol (FES) PET has been approved for clinical use in France and USA in recurrent or metastatic estrogen receptor (ER)-positive breast cancer. Indeed, [ 18 F]-FES PET/CT provides a noninvasive estimation of ER distribution, allowing therefore its application in multiple clinical scenarios, for example: (a) to stage initial metastatic disease; (b) to evaluate ER status when biopsy is difficult or non-diagnostic; (c) to assess endocrine therapy response; (d) to stage invasive lobular carcinoma and low-grade invasive ductal carcinoma which are more likely to present with BM [ 63 , 64 , 65 , 66 ].…”

Molecular imaging as biomarker for treatment response and outcome in breast cancer

“…Studies like the IMPACT-MBC trial (NCT01957332), will have to provide additional insight into the clinical utility of HER2-PET, also in HER2-negative disease. 106 At present, the clinical utility of PET imaging still remains to be established further, since most studies so far have focused on technical and clinical validity. Future studies will have to clarify which tracers have sufficient clinical utility to be considered for implementation into routine care and how this needs to be done.…”

“…Essential guidance documents that are suitable for this are the currently available appropriate use criteria105,106 and European Association of Nuclear Medicine (EANM) procedure guideline for [ 18 F] FDG-PET107 as well as the upcoming Society of Nuclear Medicine and Molecular Imaging and EANM [ 18 F]FES-PET guideline.…”