Positron emission tomography imaging of cancer biology: current status and future prospects

Positron emission tomography (PET) is one of the most rapidly growing areas of medical imaging, with many applications in the clinical management of patients with cancer. The principal goal of PET imaging is to visualize, characterize, and measure biological processes at the cellular, subcellular, and molecular levels in living subjects using noninvasive procedures. PET imaging takes advantage of the traditional diagnostic imaging techniques and introduces positron-emitting probes to determine the expression of indicative molecular targets at different stages of cancer progression. Although [(18)F]fluorodeoxyglucose ([(18)F]FDG)-PET has been widely utilized for staging and restaging of cancer, evaluation of response to treatment, differentiation of post-therapy alterations from residual or recurrent tumor, and assessment of prognosis, [(18)F]FDG is not a target-specific PET tracer. Over the last decade, numerous target-specific PET tracers have been developed and evaluated in preclinical and clinical studies. This review provides an overview of the current status and trends in the development of non-[(18)F]FDG PET probes in oncology and their application in the investigation of cancer biology.