ESTRO 2021 Abstract Book

S1541

ESTRO 2021

Figure 1. The flowchart of multi-level fusion strategy

Results The fusion models' performance was better than that from single CT/dose modality. Models combining the information of the primary tumor and lymph node region outperformed than using the single region information only. For RFS and MFS prediction, the 3mm peritumoral region model RING_3mm_nxnd had better performance than the GTV_nxnd model and RING_5mm_nxnd model (RFS: C-index 0.80vs0.75/0.69; MFS: C-index 0.75vs0.73/0.74). When combining GTV and 3mm peritumoral region information, prediction model achieved the highest C-index both in RFS and MFS predictions (RFS: 0.822; MFS: 0.786). GTV+RING_3mm GFF models can statistically separate patients into high-risk and low-risk groups in comparison to dose only or CT only models. The models were also valid for the datasets from other institutions.

Figure 2. The Kaplan-Meier curves of GTV+RING_3mm GFF models, dose model and CT model for RFS and MFS prediction.