PET/CT Characterization of Treatment Resistance

This study will use different types of medical imaging to assess how lesions from advanced prostate cancer become resistant to second-generation AR-targeted therapy, and how the different types of imaging compare in that assessment. Participants in this study have advanced prostate cancer and are either scheduled to start a second-generation androgen receptor (AR) targeted therapy (such as enzalutamide, abiraterone, or apalutamide) or are already being treated with one. Participants can expect to be in the study for at least 9 months, and up to 2 years.

Inclusion Criteria:Histologically proven adenocarcinoma of the prostate.At least 1 radiographic metastases as seen on conventional CT imaging or bone scanProgressive prostate cancer as evident by at least two separate increase in PSA over nadir, and absolute PSA value at least 2 ng/ml (INTRINSIC RESISTANCE COHORT ONLY)Patients must be candidate for a second-generation androgen receptor (AR) inhibitor (e.g. enzalutamide, abiraterone, apalutamide)Men of age >18 years.Patients must be able to comply with all study procedures, including having both the ability and willingness to lie flat for ≥ 30 minutes during imagingPatients must be informed of the exploratory nature of the study and its potential risks, and must sign IRB- approved consent form indicating such understanding.Life-expectancy at least 12 monthsPatients currently receiving a second-generation androgen receptor (AR) inhibitor (e.g. enzalutamide, abiraterone, apalutamide) and must have had 1) PSA decline on treatment and 2) now have PSA increase over nadir while still on treatment (patients must be registered within 12 weeks of first documented PSA increase) (ACQURED RESISTANCE COHORT ONLY)Exclusion Criteria:Visceral metastases (e.g. liver, lung or brain)Must not have uncontrolled diabetes (fasting blood sugar > 200 mg/dL or inability to safely hold diabetes medication or fast 6 hours prior to FDG PET scan)Prior treatment with second-generation AR inhibitor for prostate cancer in the metastatic disease setting (prior second-generation AR inhibitor in the neoadjuvant or adjuvant setting is permitted unless patient developed progression while on treatment) (INTRINSIC RESISTANCE COHORT ONLY)Pain or clinical symptoms from metastatic prostate cancer requiring opioid analgesicsKnown neuro-endocrine prostate cancerPrior cytotoxic chemotherapy or radioisotope therapy for castration-resistant prostate cancerTo avoid the possibility of unintended coercion, vulnerable populations such as incarcerated subjects, subjects unable to provide their own informed consent and non-English speaking patients will not be considered