For a review, researchers wanted to present new data on the use of moderately hypofractionated external beam radiation (defined as 2.4–3.4 Gy per fraction) and ultra hypofractionated external beam radiotherapy (also known as stereotactic body radiotherapy [SBRT]) in males with localized prostate cancer. A number of recently completed randomized studies suggest that mildly hypofractionated radiation provides comparable biochemical control to conventionally fractionated radiotherapy without increasing late toxicity. These effects appear to be consistent across all clinical risk categories at the outset. Several single-arm phase II studies, as well as a recently published large-scale randomized trial comparing SBRT to conventional fractionation, show very promising biochemical control and favorable acute and late treatment-related morbidity with SBRT in predominantly low- and intermediate-risk prostate cancer patients.

Moderate hypofractionation is a preferred alternative to conventional fractionation in the majority of men with localized prostate cancer who choose radiotherapy as their primary treatment modality because it is associated with similar prostate cancer control and toxicity while improving patient convenience and lowering cost. To present, studies mostly in low- and intermediate-risk prostate cancer have reported favorable oncologic results and tolerable toxicity with SBRT. The mature outcomes of phase III studies assessing five-fraction SBRT regimens are keenly anticipated.