Overview
Intensity-modulated radiation therapy, also called IMRT, is an advanced type of radiation therapy. Radiation therapy uses powerful energy beams to kill cancer cells. The energy can come from X-rays, protons or other sources.
With IMRT, the beams of radiation are carefully customized. The beams are shaped to match the shape of the cancer. The beams can move through an arc while they deliver the radiation. The intensity of each beam can be varied. The result is a precisely controlled radiation treatment. IMRT delivers the correct radiation dose as safely and efficiently as possible.
IMRT can be used to treat cancers and tumors that aren't cancerous, which are called benign tumors. It can treat cancers and tumors anywhere in the body.
The goal of IMRT is to deliver the correct dose of radiation to the target and minimize radiation outside of the target. This helps lower the risk of hurting nearby healthy tissue.
Why it's done
Intensity-modulated radiation therapy, also called IMRT, is used to treat cancers and tumors that aren't cancerous. The goal of treatment is to target the radiation so that nearby healthy tissue isn't hurt.
Risks
As with most medical procedures, there are risks to intensity-modulated radiation therapy, also called IMRT. The specific risks depend on which part of the body gets the radiation and how much is used.
| Part of body being treated |
Common side effects |
| Any part |
Hair loss at the treatment site that can be permanent, skin irritation at the treatment site, tiredness |
| Head and neck |
Dry mouth, thickened saliva, trouble swallowing, sore throat, changes in the way food tastes, mouth sores |
| Chest |
Trouble swallowing, cough, shortness of breath |
| Abdomen |
Nausea, vomiting, diarrhea |
| Pelvis |
Diarrhea, bladder irritation, urinating often, changes in sexual function |
If you have side effects, they often can be controlled during treatment. After treatment, most side effects go away.
Sometimes side effects develop after treatment. These are called late side effects. Very rarely, a new cancer may develop years or decades after cancer treatment. It can be caused by radiation or other treatments. This is called a second primary cancer. Ask your healthcare professional about side effects that could happen after treatment, both short term and long term.
How you prepare
To prepare for intensity-modulated radiation therapy, also called IMRT, you might have imaging tests. These tests typically are computerized tomography scans, also called CT scans, or magnetic resonance imaging, also called MRI. The images from the tests are used to make detailed pictures of the area to be treated. Radiation therapy professionals use those pictures to plan the shape and path of the radiation beams. This planning allows specific doses of radiation to be delivered to the treatment area.
What you can expect
During intensity-modulated radiation therapy, also called IMRT, you receive treatment with radiation. Based on the treatment planning, radiation therapy delivered during IMRT is carefully focused on the cancer or tumor to be treated. This lowers the amount of radiation to healthy tissue.
Results
After intensity-modulated radiation therapy, also called IMRT, you might have imaging tests to see if the cancer is shrinking. Ask your healthcare team when you can expect to know the results of your treatment. Sometimes the cancer responds to treatment right away. Other times it may take weeks or months to see the treatment working.
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