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Radiolabeled FAP inhibitors as new pantumoral radiopharmaceuticals for PET imaging: a pictorial essay


Fibroblast activation protein (FAP)-targeted radiopharmaceuticals recently emerged as potential pantumoral agent for PET imaging. FAPi PET provides the opportunity to explore the tumor microenvironment, a highly heterogeneous and dynamic system of various non-malignant cells, by assessing the overexpression of FAP in cancer-associated fibroblasts. A significant increase in FAP expression can be found in several tumor subtypes, in which has been observed an increased tumor lesion uptake associated with low and favorable background, leading to a high detection rate of tumor location(s). This pictorial essay aims to present a selection of clinical cases highlighting the potential benefit of FAPi PET in different tumor subtypes, especially considering the higher diagnostic accuracy compared to FDG PET. We present clinical cases of breast cancer, lung cancer, gastric cancer, hepatocellular carcinoma, gynecological cancers and peritoneal carcinomatosis, as well as an introduction of the biodistribution of FAPi.

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Authors would thank the Nuclear Medicine Division of the Faculty of Medicine of the Yeditepe University, Turkey and the Division of Nuclear Medicine of the S. Orsola-Malpighi University Hospital IRCCS of Bologna, Italy for providing clinical cases. At Yeditepe University 68Ga-FAPi-04 synthesis was performed within the scope of the magistral drug production permit given by the Turkey Pharmaceuticals and Medical Devices Agency (E-24931227-000-535219). The evaluation of data was approved by the local ethics committee of the Yeditepe University (Decision no: 1576).



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Correspondence to Lighea Simona Airò Farulla.

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Airò Farulla, L.S., Demirci, E., Castellucci, P. et al. Radiolabeled FAP inhibitors as new pantumoral radiopharmaceuticals for PET imaging: a pictorial essay. Clin Transl Imaging (2022).

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  • PET
  • FAPi
  • Fibroblast activation protein
  • Cancer-associated fibroblast
  • Cancer imaging