Print Overview Intraoperative radiation therapy Enlarge image Close Intraoperative radiation therapy Intraoperative radiation therapy During intraoperative radiation therapy (IORT), radiation is directed to where it's needed. The dose of IORT can be much higher than is possible with standard radiation therapy. Intraoperative radiation therapy (IORT) is a radiation treatment that's done during surgery. IORT directs radiation to the target area while affecting the surrounding tissue as little as possible. IORT is used to treat cancers that are difficult to remove during surgery. And it's used when there's a concern that tiny amounts of unseen cancer might remain. Intraoperative electron radiation therapy is the type of IORT most often used at Mayo Clinic. IORT is often combined with standard radiation therapy. Standard radiation therapy is usually done before surgery. IORT delivers higher doses of radiation than does standard radiation therapy. It's not always possible to use such high doses during standard radiation therapy because of the possibility of radiation affecting nearby organs. IORT helps keep radiation away from nearby organs.Products & ServicesA Book: Mayo Clinic Family Health Book, 5th EditionNewsletter: Mayo Clinic Health Letter — Digital EditionShow more products from Mayo Clinic By Mayo Clinic Staff Intraoperative radiation therapy (IORT) care at Mayo Clinic Request an appointment Doctors & Departments April 16, 2024 Print Show references Tepper JE, et al., eds. Intraoperative radiation. In: Gunderson & Tepper's Clinical Radiation Oncology. 5th ed. Elsevier; 2021. https://www.clinicalkey.com. Accessed Nov. 16, 2022. Jethwa KR, et al. The use of intraoperative radiation therapy in the management of locally recurrent rectal cancer. Seminars in Colon and Rectal Surgery. 2020; doi:10.1016/j.scrs.2020.100763. Mitin T. Radiation therapy techniques in cancer treatment. https://www.uptodate.com/contents/search. Accessed Dec. 1, 2022. Jethwa KR (expert opinion). Mayo Clinic. Dec. 16, 2022. Related Choroid plexus carcinoma Craniopharyngioma Intraoperative radiation therapy News from Mayo Clinic Mayo Clinic Minute: Breaking through radiation therapy myths July 26, 2023, 04:00 p.m. CDT Products & Services A Book: Mayo Clinic Family Health Book, 5th Edition Newsletter: Mayo Clinic Health Letter — Digital Edition Show more products and services from Mayo Clinic Intraoperative radiation therapy (IORT)AboutDoctors&DepartmentsCare atMayoClinic Advertisement Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. Advertising & Sponsorship Policy Opportunities Ad Choices Mayo Clinic Press Check out these best-sellers and special offers on books and newsletters from Mayo Clinic Press. Mayo Clinic on Incontinence - Mayo Clinic PressMayo Clinic on IncontinenceThe Essential Diabetes Book - Mayo Clinic PressThe Essential Diabetes BookMayo Clinic on Hearing and Balance - Mayo Clinic PressMayo Clinic on Hearing and BalanceFREE Mayo Clinic Diet Assessment - Mayo Clinic PressFREE Mayo Clinic Diet AssessmentMayo Clinic Health Letter - FREE book - Mayo Clinic PressMayo Clinic Health Letter - FREE book PRC-20304585 Patient Care & Health Information Tests & Procedures Intraoperative radiation therapy (IORT)