Biological dose escalation and hypofractionation: what is there to be gained and how will it best be done?

Abstract

The evidence supporting dose escalation for localised prostate cancer is widely accepted, but in tandem with improvements in biochemical control, dose escalation increases side-effects. In a scenario where most patients achieve control of their cancer, quality of life concerns predominate. Here we examine the biological ways in which an effective dose can be escalated without an unacceptable increase in toxicity. Possible avenues include exploiting the unusual radiobiology of prostate cancer by hypofractionation, the use of image guidance, adaptive planning and prostate motion management. We await with anticipation the results of large randomised trials of hypofractionation, moderate and profound, to establish whether we can further improve the balance between cure and quality of life.

Keywords: Biological; dose escalation; hypofractionation; image-guided radiotherapy; prostate cancer; stereotactic body radiotherapy.