Comparison of 68 Ga-FAPI and 18 F-DOPA PET/CT in patients with medullary thyroid cancer

Sep 22, 2026

Retrospective per-patient and per-lesion analyses compared 68Ga-FAPI PET/CT with 18F-DOPA PET/CT for detecting metastases in patients with recurrent medullary thyroid cancer. Imaging findings were correlated with morphological imaging or histopathology as the reference standard, and quantitative performance was assessed using standardized uptake values and tumor-to-background ratios. Across nine patients and 62 lesions, 68Ga-FAPI showed higher true-positive detection for lymph node, lung, and liver metastases, with consistently higher TBR values. Results support improved staging potential, pending confirmation in larger prospective studies.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages9

Reading Time23 min

AccessFree to download

Introduction

Methods

Results

Conclusion

TYPE Original Research PUBLISHED 24 June 2026 DOI 10.3389/fendo.2026.1824054 OPEN ACCESS EDITED BY Ileana G. Rubio, Federal University of São Paulo, Brazil REVIEWED BY Chongjiao Li, Wuhan University, China Alexander Weich, Universitätsklinik Würzburg, Germany *CORRESPONDENCE Daniel A. Hescheler [daniel.hescheler@med.ovgu.de](daniel.hescheler@med.ovgu.de) RECEIVED 05 March 2026 REVISED 28 May 2026 ACCEPTED 08 June 2026 PUBLISHED 24 June 2026 CITATION Hescheler DA, Atiyat D, Lorenz K, Heinzel A, Reschke P, Almaguel FG, Petersen M, Eppard E, Wybranska J, Wuestemann J and Kreissl MC (2026) Comparison of 68Ga-FAPI and 18F-DOPA PET/CT in patients with medullary thyroid cancer. Front. Endocrinol. 17:1824054 . doi: 10.3389/fendo.2026.1824054 COPYRIGHT © 2026 Hescheler, Atiyat, Lorenz, Heinzel, Reschke, Almaguel, Petersen, Eppard, Wybranska, Wuestemann and Kreissl. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) . The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. Comparison of 68 Ga-FAPI and 18 F-DOPA PET/CT in patients with medullary thyroid cancer Daniel A. Hescheler 1*, Dogan Atiyat 2, Kerstin Lorenz 3, Alexander Heinzel 4, Philipp Reschke 4, Frankis G. Almaguel 5, Manuela Petersen 6, Elisabeth Eppard 1, Joanna Wybranska 1, Jan Wuestemann 1 and Michael C. Kreissl 1 1 University Hospital Magdeburg, Division of Nuclear Medicine, Department of Radiology and Nuclear Medicine, Magdeburg, Germany, 2 Martin Luther University of Halle Wittenberg Faculty of Medicine, Department of Nuclear Medicine, Halle (Saale), Germany, 3 Martin Luther University Halle-Wittenberg, Halle (Saale), Department of General, Visceral and Vascular Surgery, Halle (Saale), Germany, 4 Martin Luther University Halle-Wittenberg, Halle (Saale), Department of Nuclear Medicine, Halle (Saale), Germany, 5 University Hospital Frankfurt, Department of Radiology, Frankfurt, Germany, 6 Loma Linda University Medical Center, Department of Radiology, Loma Linda, CA, United States, 7Clinic for General, Visceral, Vascular, and Transplant Surgery, Magdeburg University Hospital, Magdeburg, Germany Introduction: Accurate staging is paramount for the effective management of medullary thyroid carcinoma (MTC) . Imaging cancer-associated ﬁbroblasts utilizing Gallium-68-labeled ﬁbroblast activation protein inhibitors (FAPI) presents a novel approach for molecular imaging across various cancers, including MTC. This study aimed to compare the diagnostic accuracy of FAPtargeted imaging ( 68 Ga-RTX-1363S, abbreviated as 68 Ga-FAPI) with the established imaging standard, 18 F-DOPA, for the detection of metastases inpatients with MTC. Methods: This retrospective study compared 18 F-DOPA-and 68Ga-FAPI PET/CT imaging using per-patient and per-lesion analyses in patients with recurrent MTC. Imaging ﬁndings were correlated with morphological imaging (CT/MRI/ sonography) or histopathology as gold standard. Quantitative assessment included a comparison of standardized uptake values (SUVs) and tumor-tobackground ratios (TBRs) . Results: Nine patients (mean age 55 years, range 34–80 years) with 62 lesions were included. Compared to 18 F-DOPA, 68Ga-FAPI showed signiﬁcantly higher lesion detection rates for lymph node metastases (true-positive [TP] rate: 100%[8/8] vs. 50%[4/8]; TBR: 10 . 9 vs. 6. 9), lung metastases (TP rate: 85 .7%[12/14] vs. 42. 9%[6/14]; TBR: 6 . 1 vs. 3. 6), and liver metastases (TP rate: 100%[22/22] vs. 23%[5/22]; TBR: 24 . 1 vs. 2.7) . Conclusion: In direct comparison, 68Ga-FAPI detected a higher number of metastases with higher TBR values. 68Ga-FAPI PET/CT holds promise for imp

FAQs

What was the study’s main objective in medullary thyroid cancer imaging?

To directly compare the diagnostic accuracy of 68Ga-FAPI PET/CT versus 18F-DOPA PET/CT for detecting metastases in recurrent medullary thyroid cancer.

How were imaging results validated in the study?

Imaging findings were correlated with morphological imaging (CT/MRI/sonography) or histopathology used as the gold standard.

Which metastasis sites showed better detection with 68Ga-FAPI?

Lymph node, lung, and liver metastases all demonstrated higher true-positive detection rates and higher tumor-to-background ratio values with 68Ga-FAPI compared with 18F-DOPA.

Sep 22, 2026

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