Disease volume and distribution as drivers of treatment decisions in metastatic prostate cancer: From chemohormonal therapy to stereotactic ablative radiotherapy of oligometastases

- Chemohormonal therapy improves survival in metastatic prostate cancer.
- Stereotactic ablative radiotherapy (SABR) is emerging as an alternative for oligometastatic prostate cancer.
- Clinical trial results establishing the definite role of SABR are awaited.

The prognosis of men with metastatic, castration-sensitive prostate cancer (CSPC) depends on both the distribution and extent of metastases, among other things. Patients with low-volume or oligometastatic disease have improved survival compared with those with high-volume metastases. While chemohormonal therapy is the new standard of care for men with high-volume metastatic CSPC, stereotactic ablative radiotherapy (SABR) is emerging as a promising treatment option with low toxicity for the management of oligometastatic CSPC. Our review summarizes the current evidence on the role of SABR in oligometastatic prostate cancer. SABR shows control rates of metastases ranging from 88% to 100% at 6 months to 3 years, and progression-free survival commonly reported as >50% for the first 12 months. In addition, SABR may allow androgen-deprivation therapy to be delayed by more than 2 years in selected patients, minimizing the chronic side effects associated with such therapy. However, much still needs to be learned before SABR can be implemented as standard treatment for oligometastatic prostate cancer.