CLDN4 and neoplasm: The tumour-to-blood ratio (T/B) obtained with [111In]anti-claudin-4 at 72 h p.i. was also significantly higher for Panc-1 compared with HT1080 tumour-bearing mice (1.3 ± 0.1 and 0.4 ± 0.2, respectively; P < 0.001) and was higher compared to the T/B values obtained with [111In]mIgG in Panc-1 (0.6 ± 0.0; P < 0.001) and HT1080 (0.6 ± 0.2; P < 0.001) tumour-bearing mice.