{"entity":{"id":"intraoperative-radiotherapy","kind":"technology","name":"Intraoperative radiotherapy (IORT)","aka":[],"tldr":"Giving a single large dose of radiation directly to the tumour bed during surgery, with normal organs moved out of the way; used mainly in breast cancer as an alternative to weeks of external radiotherapy.","summary":"IORT delivers 10-21 Gy in one fraction via electrons (mobile linacs, ELIOT), low-energy X-rays (Intrabeam, TARGIT) or HDR brachytherapy applicators. In early breast cancer, TARGIT-A (BMJ 2020, long-term) showed risk-adapted IORT non-inferior for local recurrence with fewer non-breast-cancer deaths, while ELIOT (Lancet Oncol 2021) showed higher local recurrence with electron IORT than whole-breast RT (though survival was equal); ASTRO regards it as suitable for selected low-risk patients within trials or registries. Other uses: locally advanced rectal cancer and retroperitoneal sarcoma (margin boost), pancreatic cancer, paediatric tumours. Competing partial-breast approaches (5-fraction external APBI, brachytherapy) and FLASH radiotherapy overlap.","status":"established","asOf":"2026-09-08","wikipedia":"https://en.wikipedia.org/wiki/Intraoperative_radiation_therapy","links":[{"label":"TARGIT-A long-term (BMJ 2020)","url":"https://doi.org/10.1136/bmj.m2836"},{"label":"ELIOT long-term (Lancet Oncol 2021)","url":"https://doi.org/10.1016/S1470-2045(21)00080-2"}],"tags":["gap-fill"],"related":["brachytherapy-afterloaders"],"cancers":["breast-hr-positive","colorectal","sarcoma","pancreatic","breast-cancer"],"sections":["radiation","surgery"],"technologies":["brachytherapy","imrt-igrt","flash-rt"],"targets":[],"drugs":[],"companies":["carl-zeiss-meditec","intraop-medical"],"institutions":[],"pathways":[],"terms":["partial-breast-irradiation"],"trials":["targit-a","nct02685605","nct02213991","nct05498311"],"people":[],"bottlenecks":[],"keyPapers":["paper-orecchia-lancet-oncol","paper-vaidya-bmj"],"journals":[],"dependsOn":[],"notes":[],"principle":"Direct visualisation and displacement of organs at risk allow a large single fraction to the highest-risk tissue with steep dose fall-off, exploiting the radiobiology of high dose per fraction.","strengths":["Single session; completes radiotherapy during surgery","Sparing of skin, heart and lung","Useful boost for close margins in sarcoma and rectal cancer"],"limitations":["Higher local recurrence than whole-breast RT in ELIOT","Final pathology unknown at time of treatment","Equipment and workflow costs"],"since":1965},"route":"/technologies/intraoperative-radiotherapy/","neighbours":{"technology":[{"id":"brachytherapy","kind":"technology","name":"Brachytherapy","route":"/technologies/brachytherapy/"},{"id":"electron-beam-therapy-systems","kind":"technology","name":"Electron beam therapy systems (linac electrons, total skin electron units, mobile electron IORT)","route":"/technologies/electron-beam-therapy-systems/"},{"id":"flash-rt","kind":"technology","name":"FLASH radiotherapy","route":"/technologies/flash-rt/"},{"id":"imrt-igrt","kind":"technology","name":"IMRT / IGRT (modern external beam)","route":"/technologies/imrt-igrt/"},{"id":"brachytherapy-afterloaders","kind":"technology","name":"Remote afterloaders for HDR brachytherapy","route":"/technologies/brachytherapy-afterloaders/"}],"cancer":[{"id":"breast-cancer","kind":"cancer","name":"Breast cancer (all types)","route":"/cancers/breast-cancer/"},{"id":"colorectal","kind":"cancer","name":"Colorectal cancer","route":"/cancers/colorectal/"},{"id":"breast-hr-positive","kind":"cancer","name":"HR-positive / HER2-negative breast cancer","route":"/cancers/breast-hr-positive/"},{"id":"pancreatic","kind":"cancer","name":"Pancreatic ductal adenocarcinoma","route":"/cancers/pancreatic/"},{"id":"sarcoma","kind":"cancer","name":"Sarcomas (soft tissue, bone, GIST)","route":"/cancers/sarcoma/"}],"section":[{"id":"radiation","kind":"section","name":"Radiation Therapy","route":"/fronts/radiation/"},{"id":"surgery","kind":"section","name":"Surgery & Interventional","route":"/fronts/surgery/"}],"company":[{"id":"carl-zeiss-meditec","kind":"company","name":"Carl Zeiss Meditec","route":"/companies/carl-zeiss-meditec/"},{"id":"intraop-medical","kind":"company","name":"IntraOp Medical","route":"/companies/intraop-medical/"}],"term":[{"id":"partial-breast-irradiation","kind":"term","name":"Partial-breast irradiation","route":"/terms/partial-breast-irradiation/"}],"trial":[{"id":"nct05498311","kind":"trial","name":"Breast Cancer With Intraoperative Radiotherapy Followed by Hypofractionated External Beam Radiotherapy","route":"/trials/nct05498311/"},{"id":"nct02213991","kind":"trial","name":"Intraoperative Radiotherapy for Korean Patients With Breast Cancer","route":"/trials/nct02213991/"},{"id":"nct02685605","kind":"trial","name":"Intraoperative Radiotherapy in Newly Diagnosed Glioblastoma Multiforme","route":"/trials/nct02685605/"},{"id":"targit-a","kind":"trial","name":"TARGIT-A (targeted intraoperative radiotherapy)","route":"/trials/targit-a/"}],"paper":[{"id":"paper-orecchia-lancet-oncol","kind":"paper","name":"Intraoperative irradiation for early breast cancer (ELIOT): long-term recurrence and survival outcomes from a single-centre, randomised, phase 3 equivalence trial","route":"/key-papers/paper-orecchia-lancet-oncol/"},{"id":"paper-vaidya-bmj","kind":"paper","name":"Long term survival and local control outcomes from single dose targeted intraoperative radiotherapy during lumpectomy (TARGIT-IORT) for early breast cancer: TARGIT-A randomised clinical trial","route":"/key-papers/paper-vaidya-bmj/"}],"institution":[{"id":"falp-chile","kind":"institution","name":"Fundación Arturo López Pérez","route":"/institutions/falp-chile/"},{"id":"tmucih","kind":"institution","name":"Tianjin Medical University Cancer Institute and Hospital","route":"/institutions/tmucih/"}],"roadmap":[{"id":"radiation-roadmap","kind":"roadmap","name":"Radiotherapy roadmap: X-rays → shaped beams → fewer fractions, particles and FLASH","route":"/roadmaps/radiation-roadmap/"},{"id":"surgery-roadmap","kind":"roadmap","name":"Surgery roadmap: radical operations → less surgery → no surgery when a drug has done the work","route":"/roadmaps/surgery-roadmap/"}]}}