Intraoperative Radiation Therapy (IORT)

This information describes intraoperative radiation therapy (IORT) at Memorial Sloan Kettering Cancer Center (MSKCC).

IORT is a high dose of radiation that is given during surgery to remove cancer. It is used to treat cancers that are difficult to remove during surgery without damaging nearby structures, and also to destroy any cancer cells that may be left behind. IORT allows radiation to be given to the area where the cancer was removed, while doing as little damage as possible to normal surrounding tissue.

You will receive more information related to your surgery and type of cancer.

During Your Surgery

Your surgeon will remove your tumor through an incision (surgical cut). Once the tumor is removed, your surgeon will examine the nearby tissue to determine if IORT is necessary. He or she will call the IORT team into the operating room to evaluate whether you can have IORT. If you cannot have IORT, you may have another type of radiation therapy after surgery.

If the IORT team decides you can have IORT, your radiation oncologist will place an applicator that contains the radiation into the space where the cancer was removed. The applicator may be thin catheters (flexible tubes) running through a small plastic applicator (HAM applicator) or it may be a plaque, which looks like a thin film. Your radiation oncologist will decide which type of applicator to use.

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Ham Applicator

If a HAM applicator (see Figure 1) is used to give you the radiation, it will be placed in the area where the tumor was removed. The catheters that run through the applicator are connected to a machine that holds the radiation.

Once the applicator is positioned correctly, the operating staff will leave the room, close the door, and turn on the machine to begin your treatment. Although you will be alone during your treatment, the operating staff will monitor you at all times.

It will take 30 to 40 minutes for you to receive the full dose of radiation. When your treatment is done, the operating staff will come back into the room. Your radiation oncologist will remove the applicator, and your surgeon will close your incision.

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If a plaque (see Figure 2) is used to give you the radiation, it will be applied directly onto the tissue where the tumor was removed. The operating staff will stay in the room while you are receiving your radiation treatment.

It will take about 10 minutes to deliver the entire dose of radiation. When your treatment is done, your radiation oncologist will remove the plaque and your surgeon will close your incision.

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After Your Surgery

  • You will not be radioactive after the treatment. You do not need to limit contact with other people or follow any precautions.
  • You will have follow-up appointments with your surgeon and radiation oncologist. Call each office to schedule an appointment.
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Side Effects

The side effects of IORT depend on the area that was treated. Your radiation oncologist will discuss this with you during your consultation. Use the area below to write any notes.

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