ESTRO 2024 - Abstract Book

S3647

Physics - Dose prediction, optimisation and applications of photon and electron planning

ESTRO 2024

Exemplary, for a paraspinal case, we consider four treatment setups: an IMRT plan, a full VMAT arc and two different partial VMAT arcs. We solve the dose optimization problems using the open-source dose calculation tool matRad [3]. None of the Pareto plans for the full VMAT arc are dominated by any other setup. However, the best OAR sparing (at the slight cost of tumour coverage) was achieved by IMRT. The IMRT and both partial arc VMAT setups had trade-off regions where they were not the best and dominated by at least one other setup. We observe that up to 75% of plan calculations are unnecessary, leading to huge potential savings in computational effort.

Conclusion:

Using the Patch Approximation algorithm, the Pareto fronts of several treatment setups, e.g., different number of IMRT beams, IMRT vs. VMAT, different VMAT arcs, can be approximated at the same time, saving considerable amounts of dose calculations and therefore approximation time without sacrificing approximation quality.

Keywords: multicriteria optimization algorithm, IMRT, VMAT

References:

[1] Ina Lammel, Karl-Heinz Küfer, Philipp Süss (2023) An approximation algorithm for multi-objective mixed integer convex optimization. Preprint at Optimization Online, https://optimization-online.org/?p=22340. [2] Cristina Collicott, Esther Bonacker, Ina Lammel, Katrin Teichert, Michal Walzcak, Philipp Süss (2021) Interactive navigation of multiple convex patches. Journal of Multi-Criteria Decision Analysis, 28(5-6), 311-321. [3] Hans-Peter Wieser et al (2017) "Development of the open-source dose calculation and optimization toolkit matRad." Medical Physics 44.6 (2017): 2556-2568.