ESTRO 2024 - Abstract Book

S3544

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

ESTRO 2024

models have PC1 inside for at least 90% of patients. Ipsilateral lung provided good results in terms of transferability: PC1 values were inside all of FB models for ≥90% of patients.

For KB-DIBH models predictions analysis, Figure 2 A) showed good agreement among all four available models for heart, excepting for institute 6 model failing in predictions of ipsilateral lung (due to a different contouring approach). Ipsilateral lung SD V20Gy pass from 15% to 2% and SDmean from 2.8 Gy to 0.8 Gy, once excluded INST6, and inter-institute variability was quantified as 2% in the dose range from 20% to 80% (it would be 7.3% including INST6). Heart SDV5Gy was 1.3% while SDV25Gy was 0.4%, with an inter-institute variability for heart DVH predictions of 0.7% in the 20%-80% dose range. Concerning transferability, heart PC1 values were inside 94% of test set patients except for INST6 where PC1 were “out” in 3 out of 16 cases and for INST10 where PC1 were “out” in 2 out of 16 cases. PC1 ipsilateral lung values were always “in” for all institutes, once excluding INST6 (13% of cases out).