Prostate cancer - what about oligometastatic disease and stereotactic ablative radiotherapy? - a narrative review

Oligometastatic prostate cancer (OMPC) encompasses a heterogenous group of clinical entities defined by the timing of the development of metastases. These include de novo oligometastatic, oligorecurrent and oligoprogressive prostate cancer (PrCa). We describe the evidence supporting the use of stereotactic ablative radiotherapy (SABR) to the oligometastases to improve patient outcomes in each of these settings. Published clinical trials relevant to 'OMPC' and 'SABR' where used for this narrative review. The driving force behind this narrative review is the constantly evolving field of OMPC with an increasing number of salvage radiotherapy options changing the current treatment paradigm. We now have evidence to support that disease control can be optimised with SABR as shown in several practice changing trials including 'ORIOLE', 'STOMP' for PrCa and 'SABR-COMET' showing a survival advantage with a tumour agnostic salvage approach. We also describe the challenges with data interpretation and cost implications. Challenges include the small sample size for most reported trials, in combination with a lack of cost-efficiency analysis. SABR is a promising treatment approach for OMPC with a proven clinical benefit in some clinical settings and its use will expand in the future.