## 3 Results
### Impact of Rigid and Deformable Image Registration Algorithms on Mean Absorbed Doses  
In Figure 3, panels (a,c,e), respectively, the Bland-Altman analyses between D\({}_{\rm T,m}\) and D\({}_{\rm T,r}\), between D\({}_{\rm T,m}\) and D\({}_{\rm T,d}\) and between D\({}_{\rm T,r}\) and D\({}_{\rm T,d}\) are reported. The largest absolute bias was observed between D\({}_{\rm T,m}\) and D\({}_{\rm T,d}\) (\(-\)41.7 Gy). For this comparison, the 95% LOA was \(-\)70.1 and +153.5 Gy. Bias and positive (LOA+) and negative (LOA\(-\)) LOAs are reported in Supplementary Materials (Table S1 for absolute values and Table S2 for percentage values) for all the investigated dose comparisons.  
The CC indexes of mean absorbed doses for target, liver and NTL are reported in Table 2. All these indexes were statistically significant (_p_ < 0.001).  
A good correlation was found for the intra-modality comparisons of the mean absorbed doses (i.e., D\({}_{\rm r}\) and D\({}_{\rm d}\)) for all the investigated VOIs (i.e., ICC \(\geq\) 0.869, PCC \(\geq\) 0.876 and CCCo \(\geq\) 0.790). Moderate correlation was found for inter-modality comparisons (i.e., D\({}_{\rm m}\) and D\({}_{\rm r}\) or D\({}_{\rm m}\) and D\({}_{\rm d}\)), as reported in Table 2.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**VOI** & **Min Volume (mL)** & **Median Volume (mL)** & **Max Volume (mL)** \\ \hline Treated tumor & 1.3 & 118.5 & 1702.9 \\ Whole liver & 816.8 & 1580.2 & 3393.3 \\ NTL & 764.2 & 1379.3 & 2964.1 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Volumes of treated tumor and whole liver in mL.  
The CCCo among tumor mean absorbed doses (i.e., \(\rm D_{T,m}\) vs. \(\rm D_{T,r}\), \(\rm D_{T,m}\) vs. \(\rm D_{T,d}\) and \(\rm D_{T,r}\) vs. \(\rm D_{T,d}\)) were 0.602 (0.479; 0.701), 0.493 (0.368; 0.601) and 0.904 (0.856; 0.936) for HCC/CCC patients, while they were 0.579 (0.101; 0.840), 0.512 (0.065; 0.788) and 0.967 (0.913; 0.988) for metastatic patients.  
In Figure 2, panels (b,d,f), respectively, the Bland-Altman analyses between \(\rm D_{NTL,m}\) and \(\rm D_{NTL,r}\), between \(\rm D_{NTL,m}\) and \(\rm D_{NTL,d}\) and between \(\rm D_{NTL,r}\) and \(\rm D_{NTL,d}\) are reported. The largest absolute bias was observed between \(\rm D_{NTL,m}\) and \(\rm D_{NTL,d}\) (\(-2.3\) Gy).  
Figure 2: Bland–Altman plots for tumor (i.e., panels (**a**,**b**)), whole liver (i.e., panels (**c**,**d**)) and NTL (i.e., panels (**e**,**f**)) volumes according to the contouring approach.  
The difference between the predicted and the observed doses of NTL was lower than 12 Gy, suggested in [PERSON] et al. [17], in 96 out of 101 patients (deformable contouring approach) and 97 out of 101 patients (rigid contouring approach). In the remaining five of the deformable contouring group, the pre-treatment NTL mean absorbed dose always overestimated the post-treatment value, while in one out of four patients of the rigid contouring group the post-treatment NTL mean absorbed dose was higher than the pre-treatment one, probably due to a misalignment of the rigid image registration of a target with a volume of 2 mL. For this patient, nevertheless, no liver toxicity was reported after TARE treatment.  
The CCCo among NTL mean absorbed doses (i.e., D\({}_{\text{NTL,m}}\) vs. D\({}_{\text{NTL,r}}\), D\({}_{\text{NTL,m}}\) vs.D\({}_{\text{NTL,d}}\) and D\({}_{\text{NTL,r}}\) vs. D\({}_{\text{NTL,d}}\)) was 0.798 (0.710; 0.862), 0.755 (0.649; 0.832) and 0.926 (0.886; 0.953) for HCC/CCC patients and 0.913 (0.805; 0.962), 0.846 (0.632; 0.940) and 0.965 (0.889; 0.989) for metastatic patients.