FAPI-PET for Tumor Detection

Official title

68-Ga-FAPI-PET for Tumor Detection: A Prospective Observational Trial

Overview

This is a prospective observational trial investigating correlation with histopathology, positive predictive value, detection rate, reproducibility and impact on clinical management of 68-Ga-FAPI PET/CT or PET/MRI in patients receiving this imaging modality for tumor staging or restaging as part of clinical care.

Detailed description

68-Ga-fibroblast-activation-protein-inhibitors (68-Ga-FAPI) are novel Positron emission tomography (PET) tracers that were recently introduced for the imaging of patients with various cancer diseases. The fibroblast-activation-protein (FAP) is highly expressed in carcinoma-associated fibroblasts (CAFs) in the stroma of various tumor entities. The aim of this registry study is to collect data on FAPI expression, positive predictive value, detection rate, reproducibility and impact on clinical management of 68-Ga-FAPI PET/CT or PET/MRI on patients receiving this imaging modality at initial diagnosis or restaging as part of clinical care.

Primary outcome measures

• Correlation between 68Ga-FAPI PET uptake intensity and histopathologic FAP expression. Validation via immunohistochemical FAP staining/molecular analyses of pathological specimen. [Time frame: 3 Months]

Secondary outcome measures (8)

• Detection rate on a per-patient-basis of FAPI-PET for detection of tumor location, confirmed by histopathology/biopsy, clinical and conventional imaging follow-up. [Time frame: 3 Months]
• Detection rate on a per-region-basis of FAPI-PET for detection of tumor location, confirmed by histopathology/biopsy, clinical and conventional imaging follow-up. [Time frame: 3 Months]
• Positive predictive value (PPV) on a per-patient-basis of FAPI-PET for detection of tumor location, confirmed by histopathology/biopsy, clinical and conventional imaging follow-up. [Time frame: 3 Months]
• Positive predictive value (PPV) on a per-region-basis of FAPI-PET for detection of tumor location, confirmed by histopathology/biopsy, clinical and conventional imaging follow-up. [Time frame: 3 Months]
• Sensitivity and specificity of FAPI PET on a per-patient and per-region-basis for detection of tumor location confirmed by histopathology/biopsy (separate for regional, extra-regional and distant locations) [Time frame: 3 Months]
• Impact on patient management assessed by pre- and post-imaging questionnaires [Time frame: 12 Months]
• Detection rates on a per-patient basis of FAPI-PET stratified by tumor maker serum level and velocity [Time frame: 12 Months]
• Rate of up- or downstaging following FAPI-PET imaging. [Time frame: 12 Months]

Eligibility criteria

Inclusion criteria

• FAPI-PET scheduled for staging or restaging as part of clinical routine for proven or suspected malignancy
• Age ≥ 18 years.

Exclusion criteria

• Patient cannot give consent for the study
• Patient can not lie flat or tolerate FAPI PET imaging
• Unwillingness or inability to comply with study and follow-up procedures
• Condition of patient which is critical to participate in this study in the discretion of the investigators
• Pregnant, lactating, or breast feeding women.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Study design

Observational model

Cohort

Study locations

Germany · 1 center

• Department of Nuclear medicine, University hospital Essen — Essen

Publications

• Kuper AT, Vaz SC, Pabst KM, Ciuciulkaite I, Mavroeidi IA, Hamacher R, Welt A, Hammersen N, Costa PF, Djaileb L, Seifert R, Umutlu L, Schuler M, Herrmann K, Fendler WP, Kummel S, Kersting D. Comparison between [68Ga]Ga-FAPI-46 and [18F]FDG PET/CT uptake in luminal-like vs. HER2-positive breast cancer. EJNMMI Res. 2026 Mar 13;16(1):58. doi: 10.1186/s13550-026-01390-3. PMID 41824221
• Kessler L, Schwaning F, Metzenmacher M, Pabst KM, Opitz M, Wiesweg M, Aigner C, Ploenes T, Bolukbas S, Doerr F, Stuschke M, Umutlu L, Nader M, Theegarten D, Eberhardt WE, Schuler M, Herrmann K, Fendler WP, Kersting D, Hautzel H. Prognostic Value of Fibroblast Activation Protein-Directed PET Imaging in Pleural Mesothelioma. J Nucl Med. 2026 Mar 2;67(3):383-390. doi: 10.2967/jnumed.125.270906. PMID 41506801
• Watanabe M, Fendler WP, Grafe H, Hirmas N, Hamacher R, Lanzafame H, Pabst KM, Hautzel H, Aigner C, Kasper S, von Tresckow B, Stuschke M, Kummel S, Lugnier C, Hadaschik B, Grunwald V, Zarrad F, Kersting D, Siveke JT, Herrmann K, Weber M. Head-to-head comparison of 68 Ga-FAPI-46 PET/CT, 18F-FDG PET/CT, and contrast-enhanced CT for the detection of various tumors. Ann Nucl Med. 2025 Mar;39(3):255-265 PMID 39443386
• Kessler L, Schwaning F, Metzenmacher M, Pabst K, Siveke J, Trajkovic-Arsic M, Schaarschmidt B, Wiesweg M, Aigner C, Plones T, Darwiche K, Bolukbas S, Stuschke M, Umutlu L, Nader M, Theegarten D, Hamacher R, Eberhardt WEE, Schuler M, Herrmann K, Fendler WP, Hautzel H. Fibroblast Activation Protein-Directed Imaging Outperforms 18F-FDG PET/CT in Malignant Mesothelioma: A Prospective, Single-Center, O PMID 38960716
• Oster C, Kessler L, Blau T, Keyvani K, Pabst KM, Fendler WP, Fragoso Costa P, Lazaridis L, Schmidt T, Feldheim J, Pierscianek D, Schildhaus HU, Sure U, Ahmadipour Y, Kleinschnitz C, Guberina N, Stuschke M, Deuschl C, Scheffler B, Herrmann K, Kebir S, Glas M. The Role of Fibroblast Activation Protein in Glioblastoma and Gliosarcoma: A Comparison of Tissue, 68Ga-FAPI-46 PET Data, and Survival Data. PMID 38960714
• Watanabe M, Fendler WP, Grafe H, Hirmas N, Hamacher R, Lanzafame H, Pabst KM, Hautzel H, Aigner C, Kasper S, von Tresckow B, Stuschke M, Kummel S, Lugnier C, Hadaschik B, Grunwald V, Zarrad F, Siveke JT, Herrmann K, Weber M. Prognostic Implications of 68Ga-FAPI-46 PET/CT-Derived Parameters on Overall Survival in Various Types of Solid Tumors. J Nucl Med. 2024 Jul 1;65(7):1027-1034. doi: 10.2967/jn PMID 38782454

Identifiers

NCT: NCT04571086 · FAPI PET REG

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗