TY - JOUR
T1 - Comparative analysis of FES-PET/CT and FDG-PET/CT in patients with ER-positive metastatic invasive lobular breast cancer
AU - IMPACT-Metastatic Breast Consortium
AU - Moustaquim, Jasmine
AU - van Wonderen, Gabriëlle E
AU - van Geel, Jasper J L
AU - van Kruchten, Michel
AU - de Vries, Erik F J
AU - Jager, Agnes
AU - Kuip, Evelien
AU - Stokkel, Marcel P M
AU - Glaudemans, Andor W J M
AU - Brouwers, Adrienne H
AU - Hospers, Geke A P
AU - der Houven van Oordt, C Willemien Menke-van
AU - van der Vegt, Bert
AU - de Vries, Elisabeth G E
AU - Schröder, Carolina P
N1 - Copyright © 2025 The Authors. Published by Elsevier Ltd.. All rights reserved.
PY - 2025/10/16
Y1 - 2025/10/16
N2 - BACKGROUND: Detection of metastatic invasive lobular carcinoma (mILC) with standard imaging is challenging. 2-[18F]Fluoro-2-deoxyglucose (FDG) PET/CT is commonly used in the work-up of metastatic breast cancer (MBC), but may be suboptimal for mILC. 16α-[18F]Fluoro-17β-estradiol (FES) PET/CT measures estrogen receptor (ER) expression, which is generally high in mILC. To assess whether FES-PET/CT outperforms FDG-PET/CT, we compared the detection rate of both scans to identify mILC, in patients who were enrolled in the prospective IMPACT-MBC study.METHODS: Patients with newly diagnosed ER-positive mILC underwent baseline FDG-PET/CT, FES-PET/CT, diagnostic computed tomography (CT), bone scintigraphy, and a biopsy of a metastasis. The number of metastases visible on FDG-PET/CT or FES-PET/CT was compared to all metastases identified with any imaging modality. Results were analyzed at patient and lesion level.RESULTS: Twenty-six out of 200 patients had ER-positive mILC and were included in this sub-analysis. Mean number of metastases per patient was 34 (2-77) with FDG-PET/CT and 33 (0-88) with FES-PET/CT. In 12 patients (46 %), more metastases were visible on FDG-PET/CT than FES-PET/CT, in 12 patients, this was the reverse. Out of 1101 metastases detected with all imaging modalities, 889 metastases were detected with FDG-PET/CT and 859 with FES-PET/CT, resulting in a detection rate of 81 % (95 % CI 78 - 83) and 78 % (95 % CI 76 - 80), respectively. Two patients had a negative FES-PET/CT, while no patients had a negative FDG-PET/CT.CONCLUSIONS: FES-PET/CT and FDG-PET/CT have a similar detection rate in mILC, and FDG-PET/CT should be used for first-step imaging. However, as more metastases are visible on FES-PET/CT in a considerable part of mILC patients, in case of doubt, an additional FES-PET/CT should be considered.
AB - BACKGROUND: Detection of metastatic invasive lobular carcinoma (mILC) with standard imaging is challenging. 2-[18F]Fluoro-2-deoxyglucose (FDG) PET/CT is commonly used in the work-up of metastatic breast cancer (MBC), but may be suboptimal for mILC. 16α-[18F]Fluoro-17β-estradiol (FES) PET/CT measures estrogen receptor (ER) expression, which is generally high in mILC. To assess whether FES-PET/CT outperforms FDG-PET/CT, we compared the detection rate of both scans to identify mILC, in patients who were enrolled in the prospective IMPACT-MBC study.METHODS: Patients with newly diagnosed ER-positive mILC underwent baseline FDG-PET/CT, FES-PET/CT, diagnostic computed tomography (CT), bone scintigraphy, and a biopsy of a metastasis. The number of metastases visible on FDG-PET/CT or FES-PET/CT was compared to all metastases identified with any imaging modality. Results were analyzed at patient and lesion level.RESULTS: Twenty-six out of 200 patients had ER-positive mILC and were included in this sub-analysis. Mean number of metastases per patient was 34 (2-77) with FDG-PET/CT and 33 (0-88) with FES-PET/CT. In 12 patients (46 %), more metastases were visible on FDG-PET/CT than FES-PET/CT, in 12 patients, this was the reverse. Out of 1101 metastases detected with all imaging modalities, 889 metastases were detected with FDG-PET/CT and 859 with FES-PET/CT, resulting in a detection rate of 81 % (95 % CI 78 - 83) and 78 % (95 % CI 76 - 80), respectively. Two patients had a negative FES-PET/CT, while no patients had a negative FDG-PET/CT.CONCLUSIONS: FES-PET/CT and FDG-PET/CT have a similar detection rate in mILC, and FDG-PET/CT should be used for first-step imaging. However, as more metastases are visible on FES-PET/CT in a considerable part of mILC patients, in case of doubt, an additional FES-PET/CT should be considered.
U2 - 10.1016/j.ejca.2025.115792
DO - 10.1016/j.ejca.2025.115792
M3 - Article
C2 - 40976009
SN - 0959-8049
VL - 229
JO - European Journal of Cancer
JF - European Journal of Cancer
M1 - 115792
ER -