Inclusion Criteria:  Adult Patients referred for investigation of recurrent PC by PSMA PET/CT. Patients with known biochemical recurrence of a histologically confirmed primary prostate cancer, defined as:  Post prostatectomy: two consecutive PSA > 0.2 ng/ml Post-radiotherapy: a rise of 2ng/mL > post-therapy nadir (ASTRO consensus definition)  Male patients >18 years old PSA measured ± 4 weeks of the PSMA-PET/CT Patients willing and able to consent to the informed consent document  Exclusion Criteria:  Patients with ADT within 6 months prior to the PSMA-PET/CT Inability to provide informed, written consent Patients undergoing active treatment for a second non-prostatic malignancy