SGMIB is a prosthetic group used for antibody and small-protein radioiodination and possesses improved properties as a group that stabilizes 131I and maximizes the retention in tumor cells.[112,113] Remarkably, 131I-SGMIB-anti-HER2-nanobody was not retained in the kidneys, while tumor targeting was maintained. This evidence concerns the gene ERBB2 and neoplasm.