Fibroblast Activation Protein Inhibitor PET in Pancreatic Cancer.

Radiolabeled fibroblast activation protein inhibitor (FAPI) has been introduced as a promising PET tracer for imaging of pancreatic cancer. To date, FAPI PET/computed tomography (CT) has generally but not universally yielded higher radiotracer uptake and tumor-to-background contrast than 18F-fluorodeoxyglucose PET/CT in primary tumors, involved lymph nodes, and visceral metastases. It may also be useful for the evaluation of the tumor response to chemotherapy. However, increased FAPI uptake may be observed in benign conditions, including pancreatitis, pancreatic tuberculosis, IgG4-related disease, and serous cystadenoma, and therefore, clinical, radiological, and pathological correlations are required.