Abstract
1177
Objectives: 18F-FDG has been the most widely used radiotracer in oncology for PET-based characterization, staging, response assessment, and restaging of many different tumors for over three decades. However, 18F-FDG is not a tumor specific agent and cannot differentiate between increased metabolic rates due to neoplasia versus other non-neoplastic etiologies such as infection, non-infectious inflammation, and tissues with normally increased physiololgical uptake (e.g., the central nervous system). Also, some malignant lesions may not exhibit significantly increased metabolic activity on 18F-FDG PET imaging. In the recent years many new PET radiotracers other than 18F-FDG have been introduced based on the knowledge of disease-specific molecular processes of interest. Several of these radiotracers have already been used for molecular imaging in the clinic and others are currently under investigation in the clinical studies. The aim of this educational exhibit is to: I. Review some of these specific non-18F-FDG PET imaging radiotracers including 11C- and 18F-choline, 11C-methionine, 18F-DOPA, 68Ga-DOTA-somatostatin analogues, 68Ga- ligand-prostate specific membrane antigen (PSMA), 18F-PSMA, and 68Ga-fibroblast activation protein inhibitor (FAPI), including their molecular structures, as well as their specific targets and uptake mechanisms in various cancers. II. Review the current literature for their clinical diagnostic applications and performance. III. List some of their potential pitfalls, including false positive and false negative findings. IV. Discuss their potential for widespread adoption in clinical practice in the future.
