Tumor-to-liver ratios by PET/CT and biodistribution analyses were notably higher than those reported by Natarajan et al. using a similar 89Zr-labeled human αGPC3 IgG antibody and Fayn et al. using 89Zr-labeled GPC3-targeting HN3 single-domain antibodies. This evidence concerns the gene PSMB4 and neoplasm.