ESTRO 2024 - Abstract Book

S2039

Clinical - Paediatric

ESTRO 2024

No patient required general anesthesia. Due to the limited number of randomized patients, no comparison was possible between the randomization arms. Results are thus presented for the 21 patients, regardless of the SBRT scheme. Median follow-up is 81 months.

Six-months, 1-, 2- and 5-year LC rates were 85.7% (CI 67.3-96.6), 71.4% (CI 51.2-88.8%), 71.4% (CI 51.2-88.8%) and 61.3% (CI 40.7-59.3%) respectively.

Six-months, 1-, 2- and 5-year PFS rates were 71.4% (CI 47.2-86.0%), 52.4% (CI 29.7-70.9%), 52.4 (CI 29.7-70.9%), and 37.5% (CI 17.7-57.4%) respectively.

Six-months, 1-, 2- and 5-year OS rates were 100.0% (100.0-100.0%), 81.0% (56.9-92.4%), 71.4% (47.2-86.0%), 56.7% (33.3-74.7%) respectively.

With a median follow-up of 81 months, eight patients did not show any relapse (38%). Among the 13 patients who presented a relapse after hSBRT, 7/13 (54%) had a new isolated local relapse within hSBRT fields or marginal, 5/13 (38%) a distant recurrence, and 1/13 (8%) a combined failure.

Grade 2 and 3 acute RT toxicities were observed in 3 and 1 (epilepsy) patients respectively. Medium-term RT toxicity was identified in 1 patient (grade 3, brain radio-necrosis). No grade 4/5 toxicity was reported.

Conclusion:

Re-irradiation using hSBRTin children is feasible, safe and provides a short treatment course in childhood after surgery in locally relapsed ependymoma. In that case, the question whether local re-irradiation should be performed versus cranio-spinal irradiation remains unanswered and is still under debate.

This study was supported by a grant from the French Ministry of health (PHRC 2012: INCa-DGOS_5419).

Keywords: SBRT, local relapse, ependymoma

1395

Proffered Paper

Cardiac Substructure Dose and Late Cardiac Disease: Report from the Childhood Cancer Survivor Study

James E Bates 1 , Suman Shrestha 2 , Qi Liu 3 , Susan A Smith 2 , Daniel A Mulrooney 4 , Wendy M Leisenring 5 , Todd Gibson 6 , Leslie L Robison 4 , Eric J Chow 5 , Kevin C Oeffinger 7 , Gregory T Armstrong 4 , Louis S Constine 8 , Bradford S Hoppe 9 , Choonsik Lee 6 , Yutaka Yasui 4 , Rebecca M Howell 2 1 Emory University, Department of Radiation Oncology, Atlanta, USA. 2 MD Anderson Cancer Center, Department of Radiation Oncology, Houston, USA. 3 University of Alberta, Department of Public Health Sciences, Edmonton, Canada. 4 St Jude Children's Research Hospital, Department of Epidemiology and Cancer Control, Memphis, USA. 5 Fred Hutchinson Cancer Research Center, Clinical Research Division, Seattle, USA. 6 National Cancer Institute, Radiation Epidemiology Branch, Bethesda, USA. 7 Duke University, Department of Medicine, Durham, USA. 8 University of Rochester, Department of Radiation Oncology, Rochester, USA. 9 Mayo Clinic - Jacksonville, Department of Radiation Oncology, Jacksonville, USA