2. Rising PSA after definitive therapy with prostatectomy or radiation therapy (external beam or brachytherapy).
a. Post radical prostatectomy (RP) - with or without radiation. i. PSA greater than or equal to 0.2 ng/mL measured more than 12 weeks after RP. ii. \> 3 months post-surgery b. Post-radiation therapy ASTRO-Phoenix consensus definition c. May or may not be castrate resistant (list prior therapies)
3. Karnofsky performance status of 50 (or ECOG/WHO equivalent).
4. CT or as part of the PET study or performed within one month of PSMA PET.
5. Age \> 18.
6. Ability to understand a written informed consent document, and the willingness to sign it.
You may not be if
1. Undergoing investigational therapy for prostate cancer.
2. Other ongoing treatments for prostate cancer including radiation therapy, chemotherapy or androgen deprivation. Androgen deprivation within the last 4 months excluding finasteride, dutasteride or other 5 alpha reductase inhibitors (excluding castrate resistant subjects).
3. Unable to lie flat, still or tolerate a PET scan.
4. Prior history of any other malignancy within the last 2 years, other than skin basal cell or cutaneous superficial squamous cell carcinoma that has not metastasized and superficial bladder cancer.
6. Absence of PSA and total testosterone tests within 4 weeks.
