68Ga-FAPI-04 PET Distinguishes Malignancy from Inflammatory Lesions

Abstract Background The 68Ga-labelled FAPI provides new oncology imaging option other than 18F-FDG-PET. However, it's unclear about whether the FAPI-PET distinguishes malignancy from benign lesions. Methods We established an AOM/DSS-induced rat colorectal tumor model. A double PET/CT tracer of 68Ga-FAPI-04 and 18F-FDG was used in the rat colorectal tumor model. Histological examination, immunohistochemistry staining, and radioautography were performed in this study. Results 68Ga-FAPI PET imaging distinguishes neoplasia from inflammatory lesions in an AOM/DSS-induced rat colorectal tumor model, and FAPI accumulation gradually increases along with tumor progression. An inflammatory lesion did not interfere with 68Ga-FAPI PET imaging. Conclusion The 68Ga-FAPI-04 PET distinguishes malignant tumors from inflammatory lesions by detecting FAP in a rat colorectal tumor model, suggesting that 68Ga-FAPI-04 PET is a better diagnostic tool than 18F-FDG PET, at least to colorectal cancer patients.