ESTRO 2024 - Abstract Book

S4850

Physics - Quality assurance and auditing

ESTRO 2024

Conclusion:

Alanine measurements were, on average, higher than the calculated dose for all plans, but lower for Dw,m, specifically. Underdosing the PTV in this setting may be of some clinical concern. Gamma analysis showed a wide range of results and of note was that the dosimetry equipment employed in the audit was calibrated in terms of dose to water making it more challenging to assess measurements against dose calculated with Dm,m. Further work is ongoing to develop a dose to medium calibration. This audit has demonstrated that the majority of centres are delivering spine SBRT safely with acceptable dosimetric and geometric accuracy. However it has also highlighted the challenges of verifying dose calculations using Dm,m algorithms.

Keywords: SBRT, Audit, Dosimetry

References:

[1] Kry SF, Lye J, Clark CH, Andratschke N, Dimitriadis A, Followill D, Howell R, Hussein M, Ishikawa M, Kito S, Kron T, Lee J, Michalski J, Monti AF, Reynaert N, Taylor P, Venables K, Xiao Y, Lehmann J

Report dose-to-medium in clinical trials where available; a consensus from the Global Harmonisation Group to maximize consistency. Radiother Oncol 2021 doi.org/10.1016/j.radonc.2021.03.006