Journal Article

DKFZ-2024-01500

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png [68Ga]Ga-FAPI versus 2-[18F]FDG PET/CT in patients with autoimmune thyroiditis: a case control study.

Pabst, K. M.DKFZ* ; Kessler, L.DKFZ* ; Ferdinandus, J. ; Hamacher, R.DKFZ* ; Bartel, T.DKFZ* ; Siveke, J. T.DKFZ* ; Nader, M.DKFZ* ; Brandenburg, T.DKFZ* ; Desaulniers, M.DKFZ* ; Herrmann, K.DKFZ* ; Fendler, W. P.DKFZ*

2024
Springer Heidelberg

Abstract: Radiolabelled fibroblast activation protein inhibitors (FAPIs) are becoming increasingly important for imaging various tumour diseases. However, it is essential to be aware of potential pitfalls. Here, we investigate FAP expression in the thyroid gland in autoimmune thyroiditis (AIT).AIT patients with pathological thyroid uptake on [68Ga]Ga-FAPI PET were compared with glucose metabolism on 2-[18F]FDG PET in terms of SUVmax/SUVpeak/SUVmean/tissue-to-background ratio (TBR), and with a healthy control group.Between September 2019 and July 2021, 6 patients presented with a visually increased thyroid uptake and TBR on [68Ga]Ga-FAPI PET. In the retrospective clinical work-up, all patients had known or newly diagnosed AIT. Compared to a matched healthy control group, FAP expression and glucose metabolism were significantly increased ([68Ga]Ga-FAPI (SUVpeak): 7.0 vs. 1.7; p = 0.004/(TBRbloodpool): 6.8 vs. 1.7; p = 0.002; 2-[18F]FDG (SUVpeak): 3.9 vs. 1.4; p = 0.004/(TBRbloodpool): 4.0 vs. 1.2; p = 0.041). However, there was no significant difference in median uptake between [68Ga]Ga-FAPI and 2-[18F]FDG PET (SUVpeak: 7.3 vs. 5.6; p = 0.104).Patients with AIT show higher thyroid uptake on [68Ga]Ga-FAPI and 2-[18F]FDG PET. Incidental thyroid uptake is another pitfall in the interpretation of [68Ga]Ga-FAPI PET and should prompt a clinical work-up.

Note: ED04

---

Contributing Institute(s):

1. DKTK Koordinierungsstelle Essen/Düsseldorf (ED01)
2. DKTK ED Translationale Onkologie Solider Tumore (ED04)

Research Program(s):

1. 899 - ohne Topic (POF4-899) (POF4-899)

Appears in the scientific report 2024

---

Database coverage:
; ; ; ; Article Processing Charges ; Clarivate Analytics Master Journal List ; Current Contents - Clinical Medicine ; DOAJ Seal ; Ebsco Academic Search ; Essential Science Indicators ; Fees ; IF < 5 ; JCR ; PubMed Central ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

---