⁶⁸Ga FAPI PET/CT: Tracer Uptake in 28 Different Kinds of Cancer

Abstract

F luorodeoxyglucose (FDG) PET/CT is the primary imaging modality for cancer diagnosis, staging, and management. However, in cancers with high background uptake, inflammation, or low metabolic activity, FDG uptake is not as effective at tumor delineation and identifying metastatic lesions. An attractive complementary imaging target is the fibroblast-activated protein (FAP), which is preferentially expressed in cancer-associated fibroblasts. FAP overexpression is linked to increased local inflammation, suppression of lymphocyte activity, and poor prognosis in epithelial cancers. Quinolone-based FAP inhibitors (FAPIs) constitute a new strategy for targeting the tumor stroma and have been adapted as radiopharmaceuticals. However, while preliminary studies have demonstrated

Different Features of 18F-FAPI, 18F-FDG PET/CT and MRI in the Evaluation of Extrahepatic Metastases and Local Recurrent Hepatocellular Carcinoma (HCC): A Case Report and Review of the Literature

“…Follow-up laboratory examinations showed that the serum alpha-fetoprotein (AFP) level increased progressively to 71.5 ug/L (reference range: 0-3 ug/L). 18 F-FDG PET/ CT and 18 F-FAPI PET/CT were performed to further evaluate the nature of the lesion (Figure 1). 18 F-FDG PET/CT revealed multiple iso-metabolic metastases in the right mesh membrane, hypo-metabolic tumor necrosis after RFA in the right liver, and low uptake in peritoneal metastases (Figure 1A).…”

“…Integrated 18 F-FDG PET/CT has emerged as an important tool for diagnosis, staging, restaging and treatment monitoring for patients with various different types of tumors because it provides functional and morphological information in a single and noninvasive examination. 1 However, it has some limitations in the diagnosis of HCC and detecting recurrent lesions during follow-up, with little change in treatment resulting.…”

“…1 However, it has some limitations in the diagnosis of HCC and detecting recurrent lesions during follow-up, with little change in treatment resulting. 2,3 According to the literature reports, 4,5 the sensitivity of 18 F-FDG PET for detecting HCC is approximately 50-70% and has no obvious advantage compared with other imaging technologies, especially for well-differentiated HCC. Moreover, this type of disease generates a great difference between intra-and inter-operator during radiological evaluations.…”

“…7,8 FAPI-PET/CT is more sensitive than FDG PET/CT in detecting HCC lesions, including small (≤2 cm in diameter) and well or moderately differentiated tumors. 9,10 Here, we discussed different features of 18 F-FAPI, 18 F-FDG PET/CT and MRI in the evaluation of extrahepatic metastases and local recurrent HCC in a typical patient.…”

FAPI PET/CT in the Diagnosis of Abdominal and Pelvic Tumors

“…At present, PET/CT is a commonly used imaging method for the preoperative systemic evaluation and staging of malignant tumors and the glucose analog, fluorodeoxyglucose (FDG) is the most commonly used radioactive tracer for detecting malignant tumors on PET/CT (9)(10)(11)(12)(13)(14). However, FDG has weak efficacy for tumor delineation and the identification of metastatic lesions (15,16,17), making it difficult to distinguish between inflammation and malignancy on FDG PET/CT (7,(18)(19)(20).…”