[18F]AlF-NOTA-FAPI-04 PET/CT for Incidental Detection of a Benign Phyllodes Tumor in a Patient With Prior Colon Cancer.

Abstract

We present [18F]AlF-NOTA-FAPI-04 PET/CT findings of an incidentally detected benign phyllodes tumor in a 68-year-old woman with prior colon cancer. Routine contrast-enhanced CT revealed a right breast nodule with moderate enhancement, and subsequent PET/CT demonstrated intense focal FAPI uptake (SUVmax: 6.63). Histology confirmed the presence of a benign phyllodes tumor. This case highlights that FAPI-avid lesions in cancer survivors may represent benign entities with fibroblast-rich stroma, underscoring the importance of considering benign diagnoses and obtaining histologic confirmation to avoid unnecessary treatment.