Non-peptidyl (18)F-labelled PET tracers as radioindicators for the noninvasive detection of cancer.

Noninvasive molecular imaging of cancer by means of the state-of-the-art scintigraphic imaging modalities PET and PET/CT represents a powerful diagnostic approach in modern nuclear medicine. Radiotracers labelled with the prominent positron emitter (18)F can be defined as molecular PET imaging probes targeting discrete biological structures dysregulated in the progression of cancer and, thus, are capable to detect oncological pathologies in vivo at the cellular and subcellular level in a timely manner. The use of such radioindicators, also called radiotracers, allows the detection of their path and fate in the living organism. In the course of tumourigenesis, several molecular processes become dysregulated and radiotracers are available to image these abnormal characteristics. This chapter describes (18)F-labelled radiopharmaceuticals that are frequently used in oncological PET and PET/CT. In particular, non-peptidyl radiotracers for the imaging of glucose utilisation, amino acid transport and protein synthesis, membrane lipid synthesis, cell proliferation, hypoxia, oestrogen receptor status and bone mineralisation of tumours are introduced. The compounds are described regarding their radiochemical synthesis approaches and their in vivo metabolism and accumulation mechanisms. Furthermore, concrete clinical perspectives are given, that refer to highly potent and promising oncological radiotracers which are currently in preclinical development.