

IORT allows direct radiation to the target area while sparing normal surrounding tissue. IORT is used to treat cancers that are difficult to remove during surgery and when there is a concern that microscopic amounts of cancer may remain.


IORT allows higher effective doses of radiation to be used compared with conventional radiation therapy. It's not always possible to use very high doses during conventional radiation therapy, since sensitive organs could be nearby. IORT also allows doctors to temporarily move nearby organs or shield them from radiation exposure.

Intraoperative radiation therapy (IORT) care at Mayo Clinic

June 28, 2017
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  2. Mitin T. Radiation therapy techniques in cancer treatment. https://www.uptodate.com/home. Accessed March 29, 2017.
  3. Haddock MG. Intraoperative radiation therapy for colon and rectal cancers: A clinical review. Radiation Oncology. 2017;12:11.
  4. Haddock MG (expert opinion). Mayo Clinic, Rochester, Minn. April 11, 2017.

Intraoperative radiation therapy (IORT)