Several clinical studies showed additional advantages of 68Ga-PSMA PET/CT in comparison with radioactively labelled analogues of Choline (Afshar-Oromieh et al., 2014; Eiber et al., 2015), a high image contrast due to low background signal, sensitive detection of small lesions due to high radiotracer uptake, and improved detection rates of recurrent prostate cancer and metastases especially at low PSA levels. Here, KLK3 is linked to Familial prostate cancer.