AR and Familial prostate cancer: In a preliminary report by Dehdashti et al. on 20 patients with advanced prostate cancer, PET/CT scan with 18F-FDHT detected AR-positive lesions in 12 patients who were submitted to a repeated PET/CT after the administration of an AR antagonist (i.e., flutamide): in all cases, a decrease in 18F-FDHT uptake, measured both as SUV and tumor-to-muscle ratio (T/M), was registered, thus suggesting the incorporation of 18F-FDHT being a receptor-mediated process [33].