Intensity-Modulated
Radiation Therapy (IMRT)

What is IMRT?

IMRT is the most sophisticated form of external radiation that allows the radiation beam to be more precisely shaped to the tumor. With IMRT the radiation beam is segmented into several smaller beams. The physician is able to adjust the intensity of each beam to tightly conform to the shape of the tumor. This allows for delivery of the highest possible dose to the tumor while sparing surrounding, healthy tissue. This specialized technology increases the rate of tumor control, improves quality of life, reduces side effects and preserves normal organ function.

Click here to download an IMRT Patient Brochure

How is IMRT delivered?

IMRT is delivered using a machine called a linear accelerator. The patient will be positioned in a specific way on the treatment table each day before the treatment is started. Once the patient is positioned, the linear accelerator will rotate around the patient’s body, delivering multiple beams of radiation from many different angles.

How long will treatment last?

Generally the treatment time will depend on many factors such as the cancer type, location and size. Each IMRT session will take approximately 15-30 minutes. Most IMRT treatments will be delivered once or twice a day, five days per week for 4-8 weeks.

Which types of cancer can be treated with IMRT?

  • Prostate cancer
  • Head and neck cancer
  • Breast cancer
  • Lung cancer
  • Brain tumors
  • Spinal tumors
  • Pancreatic cancer

What are the side effects associated with IMRT?

Side effects with IMRT are fewer than with conventional radiation therapy because of the very precise way in which the radiation is delivered. They may vary depending on the specific area receiving radiation and may include:

  • Fatigue
  • Skin irritation
  • Loss of appetite

Side effects usually peak within the second to third week of treatment. If a patient experiences discomfort during treatment, he/she should discuss it with the treatment team. Most of the side effects can be managed through medications and changes in diet. The nurse will be able to discuss ways to make the patient feel more comfortable.

Many patients are still able to function normally while undergoing treatment; however, it is important for them to get plenty of rest and take time each day to relax. This is the time to ask for help from family members and friends.