Prospective Evaluation of 68Ga-PSMA PET-CT for Recurrence Detection of Prostate Cancer and Its Impact on Patient Management

68Ga-PSMA-ligand PET-CT is a recently developed molecular imaging technique. It is based on the prostate specific membrane antigen (PSMA), a transmembrane protein with a large extracellular domain which is over-expressed on prostate cancer cells surface. Initial experiments used a ligand to the extracellular epitope of PSMA and labelled it with the isotope 68Ga, a positron emitter (68Ga-PSMA-HBED-CC) 5. Recently published data based on more than 300 patients show recurrence detection rates and tumour to background ratios higher than choline PET-CT, even at low Prostate Specific Antigen (PSA) levels (sensitivity of 70% in PSA\<2ng/ml) 6,7. False-positive PSMA findings are not yet reported. The therapeutic management of biochemical recurrence in prostate cancer depends on the localisation and the extent of the recurrent disease. In this study, the hypothesis is that 68Ga-PSMA-ligand PET-CT, through its high diagnostic accuracy has a significant impact on the therapeutic management of patients with biochemical recurrence. Primary objective: To prospectively evaluate the impact of PSMA-PET/CT on the therapeutic management of patients with biological recurrent prostate cancer and negative, equivocal or oligometastatic disease after routine imaging diagnostic work-up. The treatment management decision will be recorded at the urologic tumor board (UTB) before and after the PSMA-PET/CT result. Rate of decision change will be calculated. Secondary objective(s) 1. To compare detection rates of PSMA PET/CT and Routine Imaging Workup 2. To search for a predictor of a positive PET scan 3. To assess diagnostic value of PSMA-PET/CT 4. To assess PSA response after targeted treatment for oligometastatic disease. 5. To evaluate the delay to start of Androgen Deprivation Therapy (ADT) from the UTB decision. 6. To evaluate the time to PSA progression.