A Case with 68Ga-FAPI Positive and 18F-FDG Negative Breast Cancer

Abstract

A female patient diagnosed of infiltrative breast carcinoma using tru-cut biopsy underwent 18flourine-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) for staging. The tumor was located in the superior external quadrant of the right breast, and did not exhibit pathological uptake in 18F-FDG PET/CT. Later, gallium-68 (68Ga) fibroblast activation protein-specific inhibitor (FAPI)-04 PET/CT imaging was performed and the primary tumor showed intense radiotracer accumulation. This presumes that 68Ga-FAPI PET/CT imaging is superior to 18F-FDG imaging in detecting the primary tumor in breast cancer, thereby suggesting the replacement of FAPI by 18F-FDG in breast-cancer staging in the future.