Clinical trials of stereotactic ablative radiotherapy for prostate cancer: updates and future direction.

Stereotactic body radiotherapy, also known as stereotactic ablative body radiotherapy (SABR), is an emerging treatment option for lung, prostate, liver and other tumors. Key factors in SABR are delivery of a high-dose radiation per fraction, proper patient positioning and target localization. Our review details the various radiotherapy techniques, dose fractionation schedules and toxicities for prostate SABR. Ongoing Phase II/III SABR studies across various risk groups have been included. It also discusses the role of conscientious focal dose escalation of the dominant intraprostatic nodule, integrating multiparametric MRI into radiotherapy protocols and finally cost-effectiveness of SABR.