POPSTAR II: This study is trying to understand whether radiation therapy plus a form of systemic therapy called radionuclide therapy is more effective than radiation therapy alone in people with oligometastatic prostate cancer who are undergoing PSMA positron emission tomography (PET) stagingLu-PSMA for Oligometastatic Prostate Cancer Treated With STereotactic Ablative Radiotherapy, a Randomised Phase II Parallel Cohort Trial

Exclusion

1. Prior systemic therapy, radiation therapy, or surgery for metastatic prostate cancer. Prior ADT is allowed but ADT within 6 months of screening for the study is not allowed. If patients have received prior ADT, serum testosterone levels must be above the lower limit of normal
2. No sites of PSMA negative metastatic disease evident on CT/bone scan
3. Any visceral (AJCCC M1c) metastases
4. Symptomatic cord compression, or clinical or imaging findings concerning for impending cord compression
5. Has a history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the trial, interfere with the patient's participation for the full duration of the trial, or is not in the best interest of the patient to participate, in the opinion of the treating Investigator
6. Has a known additional malignancy that is progressing or required active treatment in the last 2 years Note: Basal cell carcinoma of the skin, squamous cell carcinoma of the skin, superficial bladder cancer or carcinoma in situ such as breast cancer in situ that has undergone potentially curative therapy are not excluded.