Intraoperative radiotherapy (IORT)
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.
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.
How it works
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.
- Single session; completes radiotherapy during surgery
- Sparing of skin, heart and lung
- Useful boost for close margins in sarcoma and rectal cancer
- Higher local recurrence than whole-breast RT in ELIOT
- Final pathology unknown at time of treatment
- Equipment and workflow costs
Latest papers
topQuery for this technology: (TITLE:"Intraoperative radiotherapy" OR ABSTRACT:"Intraoperative radiotherapy" OR TITLE:"IORT" OR ABSTRACT:"IORT") AND (cancer OR tumor OR tumour OR oncology OR carcinoma OR lymphoma OR leukemia OR leukaemia OR myeloma OR sarcoma OR melanoma OR glioma). Results are unfiltered search hits about Intraoperative radiotherapy (IORT), not a curated reading list.