Focal Radiation With Pulsed Systemic Therapy of Abiraterone, Androgen Deprivation Therapy (ADT), Lynparza Towards Castration Sensitive Oligometastatic Prostate Cancer (FAALCON)

Inclusion Criteria: * Histologic or cytologic diagnosis of prostate adenocarcinoma (pure small cell or pure neuroendocrine prostate cancer are not allowed). * Prior radical prostatectomy OR external beam radiation with curative intent (e.g. HiFU or partial gland therapies are not acceptable) delivered to prostate. Patients with prior radical prostatectomy with positive margins must have undergone salvage or adjuvant radiation. * Have newly diagnosed oligometastatic prostate cancer based on molecular imaging (e.g. 68Ga-PSMA PET/CT or Axumin, excludes FDG-PET). Oligometastatic prostate cancer is between 1 and ≤ 5 radiation treatment sites. A site can be up to 5 cm and contain multiple lesions. * Newly diagnosed oligometastatic disease requires that no prior image guided radiation was given to sites outside of the prostate bed or pelvic lymph nodes that are typically treated in the salvage or adjuvant radiation setting. * Patients must have a PSA \>0.2 ng/mL (confirmed ≥4 weeks later with subsequent rise) for those who underwent radical prostatectomy. For those with prior curative radiotherapy, they must meet the Phoenix criteria for progression (nadir of PSA + 2 ng/mL) * Medically fit for radiotherapy * All molecular positive disease is within an anatomic distribution that (in the view of the radiation oncologist) can be treated safely per standard radiation oncology principles * Candidate for androgen deprivation therapy (e.g. leuprolide, goserelin, degarelix) abiraterone the…