Intraoperative Radiation Therapy (IORT) at the Knight Cancer Institute

A sign that says Radiation Medicine

At the OHSU Knight Cancer Institute, we provide the latest in intraoperative radiation therapy. This method, also known as IORT, enables us to deliver radiation therapy during surgery directly to affected tissue.

We offer you:

  • The most advanced technology for IORT, including Intrabeam for breast cancer and Mobetron for colon, pancreatic and other cancers. 
  • Expert radiation oncologists who will recommend IORT only when it’s suited for you and your cancer. 
  • Exceptional precision, targeting your cancer while sparing healthy cells. 

Intraoperative radiation therapy (IORT) 

What is IORT?

Radiation delivered during surgery is called intraoperative radiation therapy. It’s delivered to the “tumor bed,” the site of your tumor, right after your tumor is surgically removed. This enables us to deliver a precise dose directly to affected tissue without sending beams through healthy tissue.

The goal is to kill any cancer cells left after surgery, to lower the risk of cancer coming back. IORT also may be used to treat tumors that are too close to vital organs to be fully removed. 

Types of IORT

Types of intraoperative radiation therapy include:

A picture of a Mobetron device.
Our Mobetron device allows us to deliver radiation therapy during surgery. This can reduce the number of doses needed.
  • Mobetron: We offer the latest technology for IORT. Our Mobetron portable electron IORT device allows us to give colon cancer patients, for example, a lower overall dose in a shorter time. For some patients with pancreatic cancer, we can use the Mobetron to deliver the equivalent of 10 days of radiation therapy in one dose.
  • Intrabeam: We are the only medical center in the Northwest with the Intrabeam system for breast cancer. This treatment, for carefully selected patients, delivers one dose of radiation therapy during surgery. Intrabeam, a type of partial breast radiation, allows some patients to avoid weeks of daily external radiation therapy.

How is it delivered?

Your surgeon removes your tumor. The surgeon then moves noncancerous tissue away from the “tumor bed,” where the tumor was removed. Your body is shielded to protect it from exposure. Your doctor inserts an applicator to guide the radiation’s path, then uses a machine outside your body to deliver high-dose radiation. For some cancers, IORT can reduce exposure to healthy tissue.

What cancers is it used for? 

  • Colon cancer 
  • Breast cancer 
  • Pancreatic cancer 
  • Sarcomas 
  • Cancer in any area where it’s hard to remove

Learn more

For patients

  • Request an appointment at our Marquam Hill location: 503-494-8756
  • Request an appointment at our Beaverton location: 971-262-9400

Visit our For Cancer Patients page to find a cancer doctor and links to diagnoses.


Parking is free for patients and their visitors.

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Kohler Pavilion, fourth floor
808 S.W. Campus Drive
Portland, OR 97239
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15700 S.W. Greystone Court
Beaverton, OR 97006
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