68Ga-FAPI Outperforms 18F-FDG PET/CT in Identifying Bone Metastasis and Peritoneal Carcinomatosis in a Patient With Metastatic Breast Cancer

Abstract A 60-year-old woman, previously treated for breast cancer, was referred to gastroenterologists due to persistent abdominal distension. 18 F-FDG PET/CT revealed multiple abnormal foci at the skeleton including the bilateral ilium, peritoneum, and omentum. 68 Ga-FAPI PET/CT was performed for further detecting the primary lesion, which showed a greater number of bone metastases and higher uptake in peritoneal carcinomatoses than 18 F-FDG. Biopsy at the left ilium and omentum indicated metastases from breast cancer. This case highlighted that 68 Ga-FAPI may outperforms 18 F-FDG PET/CT in identifying bone metastasis and peritoneal carcinomatosis.