In an earlier episode, we reviewed the principles of radiation therapy from a general perspective. This field of medicine unifies the management of cancer, by harnessing the therapeutic benefits of radiation, utilising ionising radiation. A specific form of this treatment is stereotactic radiotherapy, which administers radiotherapy from different angles around the body, with the focus of ionisation meeting at the targeted tumour to be treated. This allows the focussed delivery of high-dose radiation to the tumour, whilst nearby tissues receive a much lower and thus less damaging dose - lowering the risk of side effects.