Radiotherapy
Radiotherapy is a method of treating cancerous tumours using tageted beams of radiation. The radiation is delivered by a linear accelerator, which can rotate around the patient's body to deliver the radiation from different angles.
Photograph of a patient on a linear accelerator
How Radiotherapy Works
Not all cancers are the same and different tumours need different treatment plans. The three main forms of treatment are surgery, chemotherapy (using drugs) and radiotherapy (using radiation). Radiotherapy uses precisely targeted beams of high energy photons to damage the cells of a cancerous tumour, making them unable to reproduce and spread. The high energy photon beams are created and delivered using a clinical linear accelerator which can be rotated around the patient to deliver the radiation from any direction.
Screen shot from radiotherapy planning software showing a cross section of the body and positioning of beams on the tumour

Screen shot from radiotherapy planning software showing a cross section of the body and the levels of radiation caused by the beam placement in the above image