Copper, PET/CT and prostate cancer: a systematic review of the literature

Copper is an essential element that plays an important role in both cancer development and growth. Indeed, high levels of copper have been found in prostate cancer (PCa), and this finding have paved the way for the use of this element as a target for positron emission tomography (PET) imaging. Copper64 (64Cu) can be used alone, as ⁶⁴CuCl2, and also as a precursor for the in-vitro radio-labelling of specific carriers for PET imaging in PCa, (e.g. associated to prostate-specific membrane antigen: PSMA). The use of ⁶⁴Cu-PSMA can yield late acquisitions in which PET images are characterized by a higher target-to-background ratio. At the same time, the shorter positron range of ⁶⁴Cu provides high spatial resolution, which leads to better detection of small lesions. In this context, the aim of this review was to systematically review studies evaluating the identification of PCa in humans by means of ⁶⁴CuCl2 and other PET tracers radio-labelled with ⁶⁴Cu.