Table 3. Predictive performance of the survival models.

Models	Primary cohort			Validation cohort
	C-index	95% CI		C-index	95% CI
Radiomics signature
Rad-score (ROI tumor)	0.84	0.76–0.92		0.72	0.50–0.94
Rad-score (ROI penumbra)	0.74	0.61–0.87		0.71	0.51–0.91
Rad-score (ROI liver)	0.82	0.71–0.93		0.72	0.58–0.86
Combined rad-score	0.88	0.81–0.95		0.83	0.60–0.99
Clinic-radiological model	0.86	0.79–0.94		0.70	0.48–0.91
Combined model	0.92	0.87–0.97		0.84	0.60–0.99

The combined model was set up based on independent predictors of the clinic-radiological predictors and the combined rad-score. ROI, region of interest; CI, confidence interval.