Elevated 68Ga-FAPI Accumulation in a Recurrent Angiomyolipoma

Ga-FAPI (Ga-labeled fibroblast activation protein inhibitor) PET imaging has been recently introduced for the diagnosis and staging in various malignant tumors. However, the reports about the utility of FAPI imaging in benign tumor are relatively rare. Here we report a case of pathologically proven recurrent angiomyolipoma in the left retroperitoneal area with low F-FDG uptake but diffuse heterogeneous intense Ga-FAPI uptake together with suspected lung metastases in a 53-year-old woman. Our case illustrates FAPI imaging could be helpful not only for detecting various malignant tumors but also for benign tumor like this case due to fibrotic activity in the disease.