HER2(+) BT-474 cell line and corresponding xenografts were used for <i>in vitro</i> and <i>in vivo</i> studies.<h4>Results</h4>An enhanced tumor accumulation as well as tumor-to-organ accumulation ratio was observed in pretargeted mice up to 24 h post uSPIO injection. Here, ERBB2 is linked to neoplasm.