RT Journal Article SR Electronic T1 68Ga-FAPI PET/CT: Tracer Uptake in 28 Different Kinds of Cancer JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 801 OP 805 DO 10.2967/jnumed.119.227967 VO 60 IS 6 A1 Kratochwil, Clemens A1 Flechsig, Paul A1 Lindner, Thomas A1 Abderrahim, Labidi A1 Altmann, Annette A1 Mier, Walter A1 Adeberg, Sebastian A1 Rathke, Hendrik A1 Röhrich, Manuel A1 Winter, Hauke A1 Plinkert, Peter K. A1 Marme, Frederik A1 Lang, Matthias A1 Kauczor, Hans-Ulrich A1 Jäger, Dirk A1 Debus, Jürgen A1 Haberkorn, Uwe A1 Giesel, Frederik L. YR 2019 UL http://jnm.snmjournals.org/content/60/6/801.abstract AB The recent development of quinoline-based PET tracers that act as fibroblast-activation-protein inhibitors (FAPIs) demonstrated promising preclinical and clinical results. FAP is overexpressed by cancer-associated fibroblasts of several tumor entities. Here, we quantify the tumor uptake on 68Ga-FAPI PET/CT of various primary and metastatic tumors to identify the most promising indications for future application. Methods: 68Ga-FAPI PET/CT scans were requested by various referring physicians according to individual clinical indications that were considered insufficiently covered by 18F-FDG PET/CT or other imaging modalities. All PET/CT was performed 1 h after injection of 122–312 MBq of 68Ga-FAPI-04. We retrospectively identified 80 patients with histopathologically proven primary tumors or metastases or radiologically unequivocal metastatic lesions of histologically proven primary tumors. Tumor uptake was quantified by SUVmax and SUVmean (60% isocontour). Results: Eighty patients with 28 different tumor entities (54 primary tumors and 229 metastases) were evaluated. The highest average SUVmax (>12) was found in sarcoma, esophageal, breast, cholangiocarcinoma, and lung cancer. The lowest 68Ga-FAPI uptake (average SUVmax < 6) was observed in pheochromocytoma, renal cell, differentiated thyroid, adenoid cystic, and gastric cancer. The average SUVmax of hepatocellular, colorectal, head–neck, ovarian, pancreatic, and prostate cancer was intermediate (SUV 6–12). SUV varied across and within all tumor entities. Because of low background in muscle and blood pool (SUVmax < 2), the tumor-to-background contrast ratios were more than 3-fold in the intermediate and more than 6-fold in the high-intensity uptake group. Conclusion: Several highly prevalent cancers presented with remarkably high uptake and image contrast on 68Ga-FAPI PET/CT. The high and rather selective tumor uptake may open up new applications for noninvasive tumor characterization, staging examinations, or radioligand therapy.