ESTRO 2022 - Abstract Book

S233

Abstract book

ESTRO 2022

Figure 1 shows for patient 9 that, both tri-objective BRIGHT versions result in a clear improvement in control of HSs; TPs with HSs ≤ 0.5 mL are only found using the tri-objective versions. Due to the nature of metric 2 and using a 2D plot for a 3D front, the trade-off between existing DVIs and metric 2 culminates in a larger covered area with TPs with low HS volumes. Table 1 shows that when using metric 1, for 10 out of 11 patients, total HS volume could be reduced to ≤ 0.5 mL while satisfying the clinical protocol, versus 6 out of 11 patients for bi-objective BRIGHT. Adding metric 1 does not result in worsening of DVIs. Adding metric 2 does cause slight worsening of DVIs but results in more plans satisfying the clinical protocol without HSs. Currently, using metric 1 and 2 takes 1800s and 600s, respectively. Metric 1 needs further optimization to definitively assess runtime impact. Conclusion We successfully adapted BRIGHT to reduce HSs without compromising obtainable DVI values for most patients, by explicitly computing HSs and minimizing their volume through a third objective. This could potentially render manual HS adjustments redundant.