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Pneumonia with Intense 68Ga-FAPI Uptake Mimicking Metastasis on 68Ga-FAPI PET/CT in a Patient with Rectal Cancer


  • Özge Erol Fenercioğlu
  • Ediz Beyhan
  • Nilay Şengül Samancı
  • Tevfik Fikret Çermik
  • Nurhan Ergül

Received Date: 18.07.2022 Accepted Date: 04.02.2023 Mol Imaging Radionucl Ther 2023;32(3):237-238 PMID: 37870301

A 70-year-old man with newly diagnosed rectum adenocarcinoma was referred to 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) for staging, and 68Ga-fibroblast activation protein inhibitor (FAPI)-04 PET/CT for ongoing trial. Both 18F-FDG PET/CT and 68Ga-FAPI-04 PET/CT showed intense uptake in the primary rectal tumor, and also in nodular areas in the right lung. Due to intense 68Ga-FAPI-04 and 18F-FDG uptake, the lung lesions were considered as metastases. However the lesions were reduced in size on CT after 20 days antibiotherapy and diagnosed as pneumonia.

Keywords: 68Ga-FAPI, PET/CT, CT, pneumonia


Informed Consent: Written informed consent was obtained from the participant.

Peer-review: Externally and internally peer-reviewed.

Authorship Contributions

Surgical and Medical Practices: Ö.E.F., E.B., N.Ş.S., T.F.Ç., N.E., Concept: Ö.E.F., E.B., N.Ş.S., T.F.Ç., N.E., Design: Ö.E.F., E.B., N.Ş.S., T.F.Ç., N.E., Data Collection or Processing: Ö.E.F., E.B., N.Ş.S., T.F.Ç., N.E., Analysis or Interpretation: Ö.E.F., E.B., N.Ş.S., T.F.Ç., N.E., Literature Search: Ö.E.F., E.B., N.Ş.S., T.F.Ç., N.E., Writing: Ö.E.F., E.B., N.Ş.S., T.F.Ç., N.E.

Conflict of Interest: No conflicts of interest were declared by the authors.

Financial Disclosure: The authors declare that this study has received no financial support.


  1. Kratochwil C, Flechsig P, Lindner T, Abderrahim L, Altmann A, Mier W, Adeberg S, Rathke H, Röhrich M, Winter H, Plinkert PK, Marme F, Lang M, Kauczor HU, Jäger D, Debus J, Haberkorn U, Giesel FL. 68Ga-FAPI PET/CT: Tracer Uptake in 28 Different Kinds of Cancer. J Nucl Med 2019;60:801-805.
  2. Dendl K, Koerber SA, Kratochwil C, Cardinale J, Finck R, Dabir M, Novruzov E, Watabe T, Kramer V, Choyke PL, Haberkorn U, Giesel FL. FAP and FAPI-PET/CT in Malignant and Non-Malignant Diseases: A Perfect Symbiosis? Cancers (Basel) 2021;13:4946.
  3. Erol Fenercioğlu Ö, Beyhan E, Ergül N, Arslan E, Çermik TF. 18F-FDG PET/CT and 68Ga-FAPI-4 PET/CT Findings of Bilateral Knee Osteoarthritis in a Patient With Uveal Malignant Melanoma. Clin Nucl Med 2022;47:e144-e146.
  4. Tang W, Wu J, Yang S, Wang Q, Chen Y. Organizing Pneumonia With Intense 68Ga-FAPI Uptake Mimicking Lung Cancer on 68Ga-FAPI PET/CT. Clin Nucl Med 2022;47:223-225.
  5. Liu H, Wang Y, Zhang W, Cai L, Chen Y. Elevated 68Ga-FAPI Activity in Splenic Hemangioma and Pneumonia. Clin Nucl Med 2021;46:694-696.
  6. Zheng S, Lin R, Chen S, Zheng J, Lin Z, Zhang Y, Xue Q, Chen Y, Zhang J, Lin K, You X, Yao S, Miao W. Characterization of the benign lesions with increased 68Ga-FAPI-04 uptake in PET/CT. Ann Nucl Med 2021;35:1312-1320.
  7. Pang Y, Zhao L, Luo Z, Hao B, Wu H, Lin Q, Sun L, Chen H. Comparison of 68Ga-FAPI and 18F-FDG Uptake in Gastric, Duodenal, and Colorectal Cancers. Radiology 2021;298:393-402.
  8. Çermik TF, Ergül N, Yılmaz B, Mercanoğlu G. Tumor Imaging With 68Ga-DOTA-FAPI-04 PET/CT: Comparison With 18F-FDG PET/CT in 22 Different Cancer Types. Clin Nucl Med 2022;47:e333-e339.