ESTRO 2024 - Abstract Book

S5101

Physics - Radiomics, functional and biological imaging and outcome prediction

ESTRO 2024

Results:

The bivariable outcome modelling resulted in the DVH parameters of D 0.31cc , EUD with n=0.0198, and V 82Gy,EQD2 as best predicting grade 5 bronchopulmonary bleeding, see Table 1. The first two models indicate that the dose to a small volume of the main and intermediate bronchi is the important DVH parameter for predicting grade 5 bleeding. These two models had an optimism-corrected C-statistic of 0.78 and 0.77, respectively, while the third model had a value of 0.80. However, the V 82Gy,EQD2 model had a broader confidence interval.

Table 1 . DVH parameter values, optimized parameters, and hazard ratios (HR) for the fitted univariable and bivariable models.

The NTCP model for grade 5 bleeding at 1, 2, 3, 4, and 5 years after treatment including D 0.31cc for the main and intermediate bronchi and tracheobronchial compression is shown in Figure 1. The risk is strongly dependent on the presence of tracheobronchial compression, which for the 2-year prediction is equivalent to a dose increase of 106 Gy.