AR and Familial prostate cancer: [18F]FDHT was successfully applied to image the expression of AR in tumours not only in preclinical studies, but also in patients with prostate cancer.68 Our group has tested [18F]FDHT for PET imaging of AR in the rat brain.69 Our study showed that [18F]FDHT is metabolised very rapidly in rats, and its uptake in the brain is very low.69 This results in a poor signal‐to‐noise ratio, which precludes the detection of AR in the rat brain.