Trial Activation: PR20 (NCT03784755)

Eligibility: Male, aged 18 years or older; Histologically-proven oligometstatic adenocarcinoma of the prostate and no evidence of small cell cancer; Stage:  IV (newly diagnosed at presentation or relapse after curative intent therapy); M1 disease with </= 5 metastases; N1 disease can be included as site of metastases only in patients in relapse after curative intent prostate surgery or radiotherapy; </= 3 mets in any non-bone organ system; All patients must receive Zoladex (LHRHa); all tumours must be amenable to local ablative therapy (Radiation or surgery); ECOG PS 0-1; patient is medically suitable for all treatment options.  EXCLUSION: prior adj/neoadj ADT, unless stopped >12 months & 36 mo. max duration; recurrent/metstatic disease previously treated with systemic or radiation therapy; Castration resistant prostate cancer (per PCWG3); Untreated pelvic lymph nodes as only site of disease; inability to treat all sites of disease with LAT; parenchymal brain mets.

 

Objectives: Primary objective: To compare failure free survival between patients with oligometastatic HSPC treated with standard systemic therapy plus ablative therapy to untreated prostate primary in patients with low volume metastatic disease burden versus standard systemic therapy plus local ablative therapy to all sites of disease. Secondary objectives: Radiographic Progression Free Survival; Incidence of new metastases as first event; Overall survival; Ablative treatment related adverse events (grade 3 or greater); Quality of Life (QOL); Economic analysis. Tertiary objectives: Correlative exploratory studies such as immunophenotyping to understand mechanisms of resistance to SBRT when added to standard systemic therapy and identify predictive/prognostic markers in the trial population, and to create a biorepository of tissue and blood for future correlative studies.