ESTRO 2025 - Abstract Book

S3235

Physics - Intra-fraction motion management and real-time adaptive radiotherapy

ESTRO 2025

After FM and DM registration, the variations in the GTV centroids between the reference phase (end-expiratory 50% phase) and the other 9 phases were calculated for each method, along with the total GTV incorporating these variations. The Wilcoxon signed-rank test was used for the comparison, and the significance level was set at 0.05. P values were adjusted using the Bonferroni correction for multiple comparisons across respiratory phases. Results: In FM, the median variations between the GTV centroids in the reference phase and the other 9 phases was 1.1 mm (interquartile range [IQR]: 0.4–1.7 mm): 0.4 mm in lung cancer and 1.3 mm in pancreatic cancer. In DM, the median variations between the GTV centroids in the reference phase and the other 9 phases was 3.7 mm (IQR: 1.5–6.3 mm): 4.0 mm in lung cancer and 3.4 mm in pancreatic cancer. In most inspiratory phases, the variations from the reference phase in DM were significantly larger than those in FM for both lung cancer and pancreatic cancer (Figure 2).