Radiation therapy or radiotherapy is a term known to cancer sufferers. It is one of the three techniques to cure different types of cancers in the world today. With this being said, the other two are surgery and chemotherapy. On the other hand, chemotherapy is more associated with the cancer word and is more popular.

There are four types of radiation therapies. They are the conventional and conformal, intensity modulated radiation, 'stereotactic' radio surgery ('SRS') and image guide radiation therapy ('IGRT').

For conventional and conformal therapy, it is a technique that applies to basic and simple cases. It uses one or two beam directions to irradiate the target (cancer tissues or cells) without complex shielding (for example, the whole brain, spine 'methastases', etc.) It applies multiple beams directions to conform as closely as possible to the target volume to deliver adequate dose to the tumour and at the same time minimizing dose to normal tissues nearby. Both conventional and conformal techniques are based on 3D anatomic information to gather close distributions.

Next, we have the 'IMRT' or Intensity Modulated Radiation Therapy. It is the most advanced treatment technology type we have, which enables 'non' uniform radiation to be delivered to the patient from any given position of beam, to optimize the composite dose distribution. 'IMRT' treatment is superior to the previous technique, in terms of sparing of normal tissues and organs. This enables higher doses to be delivered to the cancerous cells without increasing side effects. This means better cancer cure in many cases.

'Stereotactic' radio surgery or 'SRS' is a 'non' surgical procedure that uses highly focused radiation beams to treat certain types of tumours, inoperable lesions and as a post operative treatment to eliminate any leftover tumour tissues or to obliterate (destroy) abnormal blood vessels in congenital 'arteriovenous' malformations. This procedure relies on detailed imaging, computerized treatment planning and precise treatment setup with extreme accuracy. It is only delivered once or several times, depending on the dose prescribed by the oncologist.

Lastly, 'IGRT' or Image Guided Radiation Therapy would be an option. It has the advantage of accuracy during delivery of the treatment. The human body is unique in a way that is always moving. And this movement reflects the behaviour of the organs. As organs move, the tumour can also move between treatments due to differences in organ filling or movements while breathing. 'IGRT' is an imaging method on a real time basis where an image of the patient is taken and compared to the planning image, prior to the treatment.