AFP and neoplasm: Further analysis of the tumour size dependence of iRGD-induced elevation of the blood AFP concentration revealed that iRGD elicited a much higher increase of the absolute blood AFP concentration in mice with larger HCCs as compared to mice with smaller HCCs (Fig. 4c), in agreement with the hypothesis that iRGD-induced tumour-blood transport of AFP depends on the amount of AFP in the tumours.