What is Intensity Modulated Radiotherapy (IMRT)?
IMRT has evolved from 3DCRT; it uses all the advanced features which are an integral part of 3DCRT. 3DCRT and IMRT use a combination of trajectories (fields) which are shaped to match the shape of the tumour. IMRT differs from 3DCRT as it provides superior dose distribution to the treatment field. 3DCRT delivers the same dose of radiation to the entire treatment field. IMRT varies the amount/intensity of dose delivered within different segments of the treatment field.
Example of a lung tumour treated by 3DCRT (see fig. A) versus IMRT (see fig. B). IMRT allows better irradiation of the tumour, while minimising the irradiated amount of lung and heart
How does IMRT work?
A radiation oncologist at a network location uses three-dimensional computerised scans to visually outline the location of the tumour and surrounding normal tissue. Once this step is completed, the information is transferred electronically to UPMC’s team of world-class physicists. These specialists use virtual reality simulation to plot a radiation treatment targeting the exact shape of the tumour. An optimal plan can require hours of calculations, taking several days to complete.
Once the target is plotted, the treatment plan is then sent back to the Cancer Centre and is transferred electronically to a linear accelerator, the machine used to deliver radiation treatments. Radiation beams are delivered in approximately 300 different segments, focusing the radiation on the tumour while minimizing the dose passing through normal tissue.
What does this mean for patients?
Standard radiation therapy affects both cancerous and normal surrounding tissue, causing side effects such as diarrhoea, abdominal pain and mouth and throat ulcers. With IMRT technology, patients experience significantly lower treatment-related side effects. IMRT also offers the potential for higher cure rate
Cancer care that is right for you
Your oncologist will be able to tell you if IMRT technology should be a part of your treatment plan. At UPMC Cancer Centres, we pride ourselves on the level of cancer care we are able to provide each patient. Exceptional treatment is always the standard of care.
What can I expect from this procedure?
3-D conformal therapy has been shown to improve outcomes for a number of cancer types, including head and neck, lung, liver, prostate and braincancers. This technique is the most widely used for treated cancers with radiation and is the technique available in all cancer centres in Ireland.