Patients with biochemical reoccurrence (post-prostatectomy or post radical radiotherapy) or patients with biochemical relapse with rising PSA in spite of taking hormone treatment (this situation is characterized as non-metastatic castration resistant prostate cancer M0CRPC) and compare it to bone scan and CT in 2 groups:

PSA >= 0.2 ng/mL and <= 0.5 ng/mL or PSA > 0.5 ng/ml

Patients with high risk prostate cancer who have not received any definitive treatment. These high-risk patients are defined using the D'Amico Classification System: Those with a PSA of more than 20, or a Gleason score equal to or greater than 8, or have a clinical stage greater than T2c.

Administration of 68Ga-PSMA-11 followed by a PET/CT scan at 45 min after injection.

PET/CT images, CT-alone images and bone scans will be read by separate readers who will not be blinded to all other clinical and imaging information. A target lesion list will be created, finalized and entered into the research study file. Reviewer will assign each patient an overall likelihood of prostate cancer score, equal to the highest score of any target lesion on the PET/CT scan. Following the entry of final PET/CT, CT-only and bone scan target lesion lists and overall likelihood scores into the study file, all the experienced readers will become un-blinded and adjudicate by consensus in conjunction with referring physicians all lesions identified by each on their respective datasets and will assign a final consensus to each lesion. Each target lesion identified by each reader will be followed clinically, radiologically and histopathologically over a minimum period of 6 months and the final consensus can be modified based on this follow-up.

Immediate and delayed adverse events will be captured for every patient and will be analysed at the end of study.