As a new dual targeting PET radiotracer, 18F-FAPI-Biotin is promising as an excellent imaging agent applicable to various cancers. In this study, we observed the safety, biodistribution and radiation dosimetry of 18F-FAPI-Biotin in patients with various types of cancer and compared them with the results of 18F-FAPI or 18F-FDG imaging to evaluate the dosimetric characteristics and diagnostic efficacy of 18F-FAPI.

Fibroblast activation protein (FAP) is highly expressed in the stroma of a variety of human cancers and is therefore considered promising for guiding targeted therapy. The recent development of quinoline-based PET tracers that act as FAP inhibitors (FAPIs) demonstrated promising results preclinically and already in a few clinical cases. Biotin is overexpressed in various tumor cells and underexpressed in normal cells. We assume that expanding molecular probes targeting FAPI and biotin with dual targets to enhance the targeting ability of the tracer, improve the sensitivity and specificity of tumor lesion detection. 18F-FAPI-Biotin is a novel dual targeting tracer. The present study aimed to evaluate the biodistribution, pharmacokinetics, and dosimetry of 18F-FAPI-Biotin, and performed a head-to-head comparison with 18F-FAPI or 18F-FDG PET/CT scans in patients with various cancers.

Inclusion Criteria:

• Various solid tumors with available histopathological findings • Signed informed consent

Exclusion Criteria:

• pregnant or lactational women • who suffered from severe hepatic and renal insufficiency