Image-guided radiation therapy (IGRT)

Overview

Image-guided radiation therapy, also called IGRT, is a type of radiation therapy. Radiation therapy uses powerful energy beams to kill cancer. The energy can come from X-rays, protons or other sources. In IGRT, images are used to help plan the treatment.

When undergoing IGRT, high-quality images are taken before each radiation therapy treatment session. The images are used to increase the accuracy and precision of the radiation treatment.

IGRT may make it possible to use higher doses of radiation. This may increase the effectiveness of the treatment and may result in shorter treatment schedules. The radiation may reach less of the healthy tissue around the target.

IGRT is the standard of care for radiation therapy treatment. It's used to treat all types of cancer. It's also sometimes used to control tumors that aren't cancerous.

Why it's done

Image-guided radiation therapy, also called IGRT, is a type of radiation therapy. IGRT is used to treat all types of cancer. It's also sometimes used to control tumors that aren't cancerous. IGRT is particularly ideal for tumors and cancers located very close to sensitive structures and organs. IGRT also is useful for cancers that are likely to move during treatment or between treatments.

Risks

As with most medical procedures, there are risks to image-guided radiation therapy, also called IGRT. 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, extreme tiredness
Head and neck	Dry mouth, thickened saliva, difficulty swallowing, sore throat, changes in the way food tastes, nausea, mouth sores, tooth decay
Chest	Difficulty 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

Before image-guided radiation therapy, you may meet with a doctor who specializes in using radiation to treat cancer. This doctor is called a radiation oncologist. Together you may talk about whether image-guided radiation therapy, also called IGRT, is right for you.

If you decide to move forward with IGRT, your radiation therapy team carefully plans the treatment. The team may choose one or more imaging types to precisely locate the cancer and sensitive organs.

IGRT may involve a variety of 2D, 3D and 4D imaging techniques to plan the treatment, position your body and aim the radiation so that it is carefully focused on the cancer. This helps to minimize harm to healthy cells and organs nearby.

What you can expect

During image-guided radiation therapy, imaging tests are done before, and sometimes during, each treatment session. Your radiation therapy team compares these images to ones taken previously to determine if your cancer has moved and adjust your body and your treatment to target the cancer more precisely.

Results

After image-guided radiation therapy, 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.