What is radiotherapy?

Man on table

External beam radiotherapy is the use of high energy X-rays used to treat cancer or sometimes benign disease. It can be delivered as a stand-alone treatment option or before or after surgery, before, during or after chemotherapy and alongside hormone treatment. The body is made up of building blocks called cells, the radiotherapy works by damaging the cancer cells. Although, some normal cells will be in the treatment area, most are able to repair and recover from the radiotherapy.

External beam radiotherapy is delivered by a linear accelerator (Linac). The Spire Specialist Care Centre has the latest in state-of-the-art Linac Technology.

Radiotherapy treatment can be given over a number of days (fractions) this can enable a larger dose of radiation to be given whilst helping to minimise the treatment to the surrounding normal tissue. This approach can help to minimise side effects from the radiotherapy. The treatment can also be given in a single treatment or a shorter course dependent on the purpose of radiotherapy. Your doctor will discuss with you the intended number of treatments and the reasoning why.

The Purpose of Radiotherapy

Radiotherapy treatment is given with two different intentions:

Radical (Curative) Intent: The aim of this is to give long term benefit from the radiotherapy treatment. 

Palliative treatment aims to shrink tumours and relieve cancer symptoms and pain.  It can also help to prolong life.


Treatments that will be routinely offered in the centre:

Intensity Modulated Radiotherapy (IMRT) – Allows treatment to be shaped around structures that need to be avoided whilst the intensity of a radiation beam can be varied to produce areas of high and low dose within a treatment beam dependent on the patient’s tumour and location.  This variation optimises the effectiveness of the radiotherapy treatment.  To enhance the precise planning and treatment using IMRT daily image guided radiotherapy (IGRT) is used.

Volumetric Modulated Arc Therapy (VMAT) – This is an IMRT treatment technique that utilises the linear accelerator moving in an arc rotation to reduce the time the patient is on the treatment machine, whilst ensuring optimal dose to the tumour and reducing the dose normal tissues receive.

Image Guided Radiotherapy (IGRT) – A planning CT scan is used to tailor, design and plan patient specific treatments.  The images acquired from the initial CT scan are used to provide baseline reference images. This ensures treatment accuracy and positioning, daily images are taken and compared to the original planning CT scan. IGRT can be achieved by a number of techniques from two dimensional X-ray images to three dimensional cone beam images acquired on a radiotherapy treatment machine pre to and during daily treatments.  IGRT offers the benefit of using advanced imaging systems to precisely position the radiotherapy treatment and target the tumour.