- The 5-year real-world ipsilateral recurrence rate with intraoperative radiation therapy (IORT) was 6.6% in the observational TARGIT-R study of patients with early breast cancer.
Why this matters
- IORT is an experimental procedure consisting of the delivery of a single dose of radiation in the operating room to the lumpectomy cavity.
- The real-world findings are worse than the 2.1% reported for the randomized controlled TARGIT-A trial.
- More research is needed before IORT can be considered a viable treatment option.
- TARGIT-R is a retrospective cohort study of 667 patients in North America given IORT.
- Primary outcome was ipsilateral breast tumor recurrence (IBTR).
- Funding: None.
- Median follow-up was 5.1 years.
- IBTR rates:
- All patients: 6.6%.
- With primary IORT: 8%.
- With unintended boost cohort: 1.7%.
- With delayed IORT: 0%.
- With intended boost IORT: 0%.
- With primary IORT with adherence to endocrine therapy: 3.9%.
- Those with nonadherence to endocrine therapy and receiving IORT had a 5-year IBTR risk >3.5 times higher (HR, 3.67; 95% CI, 1.66-8.11) than those with endocrine therapy adherence and IORT.
- Retrospective, observational study.