External beam radiation therapy (EBRT) can be given using different techniques and types of radiation. The radiation oncologist will recommend the most suitable method for you. If you need a type of radiation therapy that is not available at your local hospital, they may arrange for you to have it at another centre.
Learn more about these types of EBRT:
- Three-dimensional conformal radiation therapy (3DCRT)
- Intensity-modulated radiation therapy (IMRT)
- Volumetric modulated arc radiation therapy (VMAT) or Rapid Arc
- Image-guided radiation therapy (IGRT)
- Stereotactic radiosurgery (SRS) and stereotactic radiation therapy (SRT)
- Stereotactic body radiation therapy (SBRT)
Three-dimensional conformal radiation therapy (3DCRT)
| What is it | Most common type of EBRT |
| When used | Used to treat many different types of cancer |
| How it works | The radiation beam is shaped (conformed) to fit the treatment area; this means that the tumour receives most of the radiation, and healthy tissues receive much less |
| Machine type | LINAC |
| How often | Usually once a day, Monday to Friday |
Intensity-modulated radiation therapy (IMRT)
| What is it | Highly accurate type of conformal radiation therapy |
| When used | Used for most types of cancer, especially for curative treatment |
| How it works | Shapes and divides multiple beams of radiation into tiny beams (beamlets) to closely fit the tumour while healthy tissue nearby receives lower doses of radiation therapy |
| Machine type | LINAC |
| How often | Once a day, Monday to Friday |
Volumetric modulated arc radiation therapy (VMAT) or Rapid Arc
| What is it | Type of IMRT |
| When used | Used for many types of cancer, especially if near sensitive body organs |
| How it works | Machine moves around you and reshapes and changes the intensity of the radiation beam to the tumour |
| Machine type | LINAC |
| How often | Once a day, Monday to Friday |
Image-guided radiation therapy (IGRT)
| What is it | Uses x-rays or CT scans at the start of each session to check that you are in the correct position for treatment |
| When used | May be recommended for cancer in areas that are likely to move a lot, such as the lungs from breathing |
| How it works | Repeated imaging allows for your position or radiation dose to be adjusted during treatment; this helps protect normal tissue |
| Machine type | LINAC or MR-LINAC (combines MRI with LINAC) |
| How often | Once a day, Monday to Friday |
Stereotactic radiosurgery (SRS) and stereotactic radiation therapy (SRT)
| What is it | Specialised type of radiation therapy; SRS is not surgery and does not involve any surgical cuts |
| When used | Used for brain tumours |
| How it works | Many small beams of radiation are aimed at the tumour from different directions to target the exact shape of the tumour |
| Machine type | LINAC but may use a CyberKnife or Gamma Knife machine |
| How often | Can vary, usually given in one dose |
Stereotactic body radiation therapy (SBRT) or stereotactic ablative body radiation therapy (SABR)
| What is it | Delivers tightly focused beams of high-dose radiation precisely onto the tumour from many different angles |
| When used | May be used to treat small cancers in the body, including small lung or liver cancers or small metastases (cancer that has spread away from the primary cancer) |
| How it works | Combines many small beams of radiation from different angles to target the exact shape of the tumour |
| Machine type | LINAC or Gamma Knife machine |
| How often | Up to five doses, given once a day |
Key resource
Download a PDF booklet on this topic.
More resources
Prof June Corry, Radiation Oncologist, GenesisCare, St Vincent’s Hospital, VIC; Prof Bryan Burmeister, Senior Radiation Oncologist, GenesisCare Fraser Coast, Hervey Bay Hospital, and The University of Queensland, QLD; Sandra Donaldson, 13 11 20 Consultant, Cancer Council WA; Jane Freeman, Accredited Practising Dietitian (Cancer specialist), Canutrition, NSW; Sinead Hanley, Consumer; David Jolly, Senior Medical Physicist, Icon Cancer Centre Richmond, VIC; Christine Kitto, Consumer; A/Prof Grace Kong, Nuclear Medicine Physician, Peter MacCallum Cancer Centre, VIC; A/Prof Sasha Senthi, Radiation Oncologist, The Alfred Hospital and Monash University, VIC; John Spurr, Consumer; Chris Twyford, Clinical Nurse Consultant, Radiation Oncology, Cancer Rapid Assessment Unit and Outpatients, Canberra Hospital, ACT; Gabrielle Vigar, Nurse Unit Manager, Radiation Oncology/Cancer Outpatients, Cancer Program, Royal Adelaide Hospital, SA.
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