ESTRO 2024 - Abstract Book

S4661

Physics - Optimisation, algorithms and applications for ion beam treatment planning

ESTR0 2024

Results:

The CTV dose coverage was kept within clinically acceptable limits and the CG OARs were fulfilled in all nominal plans. The optimal minLET d values showed no dependence on CTV volumes. Conversely, the robustness of the plan declined and the D1 in the CTV increased as the minLET d increased (Figure 1). The average optimal minLET d over all plans was 48.6 keV/μm. The mean L98 in the GTV significantly increased (p<0.001) from 31.62±2.03 to 47.27±3.32 keV/μm, while statistically relevant changes (p<0.01) were reported on the CTV and GTV L50 with an average increase of 8.01 and 11.92 keV/μm, respectively (Figure 2). The V50 LET in the GTV increased on average by 36%. The discrepancy between LEM and mMKM was reduced on average by 3 Gy(RBE) on GTV D95. No statistically significant difference was found in plans homogeneity (p>0.05).