Fibroblast Activation Protein–Targeted PET/CT Imaging in a Treatment-Naive Prostate Cancer Patient With Low PSMA Expression

Abstract Prostate-specific membrane antigen (PSMA) PET/CT has become increasingly accepted for imaging prostate cancer (PCa), including its recent use in primary staging. In this case report, we present the case of a 76-year-old man with newly diagnosed PCa. 18 F-PSMA-1007 PET/CT showed minimal PSMA activity in the primary tumor and metastases. However, 18 F-FAPI-04 PET/CT revealed more avid lesions in primary tumor, metastatic lymph nodes, and bones. Subsequent histopathologic examination confirmed the diagnosis of PCa. These findings suggest that 18 F-FAPI-04 may have a potential role in the evaluation of PCa with low PSMA expression in treatment-naive patients.