18F-Fluciclovine

[18F]Fluciclovine is a leucine analogue which similar to other radiolabeled amino acids shows high uptake in cancer cells, where increased protein turnover and nucleotide synthesis characterize the metabolic demands of the proliferating tissue. Although it was originally conceived for the study of brain tumors and could be potentially useful for molecular imaging of different types of malignancies, this metabolic tracer has been registered and approved by the American and European drug regulatory authorities for the detection of prostate cancer in patients with elevated prostate-specific antigen (PSA) levels following primary curative treatment. Despite the improvement of surgical and radiotherapy techniques in the treatment of localized prostate cancer, a variable percentage of patients meet a subsequent increase in PSA levels after primary curative treatment. Recurrent prostate cancer still remains a diagnostic and therapeutic dilemma, since conventional imaging, including contrast-enhanced computed tomography (CT), magnetic resonance imaging (MRI), and bone scan, often fails to identify the site of relapse and to differentiate a local from a systemic progression, especially for low PSA levels. Molecular imaging with radiopharmaceuticals such as [18F]/[11C]choline in the management of patients with biochemical recurrence of prostate cancer has been in use for several years, while more recently innovative tracers, such as the prostate-specific membrane antigen (PSMA), labeled with [68Ga] and less frequently with [64Cu] or [18F] or [18F]fluciclovine have been proposed with the aim of identifying earlier and with higher sensitivity disease recurrence with low tumor burden. Since first experimental studies have shown high levels of [18F]fluciclovine uptake in prostate cancer, this radiopharmaceutical has been evaluated in the context of the different possible clinical scenarios of patients affected by prostate cancer, both in localized forms than in regional or distant disease. The purpose of this chapter is to describe the main characteristics and properties of [18F]fluciclovine, with particular attention to the synthesis process, pharmacokinetic and pharmacodynamic properties, and clinical applications, mainly with regard to prostate cancer.