Eligibility Criteria for Comparison S

Inclusion Criteria:

1. Patient still meets all eligibility criteria for registration in Section 4.4 of the STAMPEDE2 protocol.

2. Histological confirmation of prostate adenocarcinoma.

3. Newly diagnosed (de novo) metastatic disease that is considered eligible for SABR according to the definition in Section 4.6 of the STAMPEDE2 protocol.

4. Patient has started ADT and randomisation is ≤12 weeks since the start of ADT.

5. WHO performance status 0-2 (see Appendix 1 of the STAMPEDE2 protocol). 

6. Patient has provided signed informed consent for participation in Comparison S.

Exclusion Criteria:

1. Patient has relapsed prostate cancer.

2. Prior radical treatment to the prostate (e.g., radical surgery and/or radiotherapy).

3. Intracranial metastatic disease.

4. Prior treatment to a metastatic site (e.g., radiotherapy, surgery or RFA).

5. Significant or progressive neurological deficit such that emergency (within 24 hours) surgery or radiation required (e.g., metastatic spinal cord compression, or impingement of the cord or any other clinical scenario whereby urgent radiotherapy to the spine is required).

6. Any condition or co-morbidities that, in the judgement of the clinician, preclude procedures required to facilitate radiotherapy delivery e.g: 

   a) Disease staging and follow-up.

   b) Radiotherapy planning procedures.

7. Any condition or co-morbidities that, in the judgement of the clinician, preclude the safe delivery of radiotherapy to the prostate (+/- pelvic lymph nodes) and/or metastases e.g., inflammatory bowel disease, significant systemic connective tissue disorder, radiological evidence of idiopathic pulmonary fibrosis).

8. Active malignancy other than prostate cancer within the last 36 months.