ERBB2 and breast cancer: MDA‐MB‐468 cells.429 MDA‐MB‐468 xenografts.429 Transgenic mouse model of HER2 (human epidermal growth factor receptor 2)/neu overexpression‐driven breast cancer: tumor formation could be detected earlier with the SPECT probe (after 96 days) than with DCE‐MRI (dynamic contrast enhanced magnetic resonance imaging) (after 120 days) or by palpation (after 131 days).430