Prostate cancer has relatively poor uptake of 18F-FDG, however 90-100% of localised prostate cancers (as well as lymph node and bone metastases derived from them) express the prostate-specific membrane antigen receptor (PSMA). PSMA expression has been correlated with tumour progression, and also with androgen independence – thus detecting PSMA expression can be an early indication that androgen-deprivation therapy is no longer effective. Expression of PSMA is also a prognostic indicator for the recurrence of disease. Imaging expression of PSMA has recently become possible with a variety of gallium-labelled short peptides, such as 68-Ga-PSMA-HBED-CC.