18F-FAPI and 18F-FDG PET/CT in Patients With Various Types of Cancer

A Prospective Study on Comparison 18F-FAPI and 18F-FDG PET/CT in the Evaluation of Patients With Various Types of Cancer

FAP is overexpressed in the cancer-associated fibroblasts (CAFs) of 90% epithelial carcinomas. Currently, 68Ga-fibroblast activation protein inhibitor (FAPI) has shown promising diagnostic value in many types of tumors. However, there are currently no studies on head-to-head comparison of diagnosis value of various types of cancer in 18F-FAPI and 18F-FDG PET/CT. Therefore, we conducted a prospective study to investigate the value of 18F-FAPI PET/CT in various types of cancer, and compare it with 18F-FDG PET/CT.

Fibroblast activation protein (FAP) is a serine protease that belongs to the dipeptidyl peptidase-IV (DPP-IV) family located in fibroblast membranes. FAP is overexpressed in the cancer-associated fibroblasts (CAFs) of 90% epithelial carcinomas, including primary and metastatic liver cancer. Therefore, FAP-targeted radiopharmaceuticals can be considered a promising approach for the visualization of CAFs. CAFs are crucial component of tumor stroma, promote the growth of cancer cells and are associated with poor prognosis. Currently, Gallium 68 (68Ga)-fibroblast activation protein inhibitor (FAPI) has shown promising diagnostic value in many types of tumors, including lung cancer, gastric carcinomas, peritoneal carcinomas. However, there are currently no studies on head-to-head comparison of diagnosis value of various types of cancer in 18F-FAPI and 18F-FDG PET/CT. Therefore, we conducted a prospective study to investigate the value of 18F-FAPI PET/CT in various types of cancer, and compare it with 18F-FDG PET/CT.

Inclusion Criteria:

1. adult patients (aged 18 years or order);
2. patients with suspected or newly diagnosed or previously treated malignant tumors (supporting evidence may include CT, MRI and pathology report);
3. patients who had scheduled both 18F-FAPI PET/CT and 18F-FDG PET/CT scans;
4. patients who were able to provide informed consent (signed by participant, parent or legal representative) and assent according to the guidelines of the Clinical Research Ethics Committee.

Exclusion Criteria:

1. patients with non-malignant lesions;
2. patients with pregnancy;
3. the inability or unwillingness of the research participant, parent or legal representative to provide written informed consent.