According to the clinical trial registration, “The primary aim of this study was to compare SPECT/CT imaging properties of [99mTc]Tc-ADAPT6 and [99mTc]Tc-(HE)3-G3 in HER2-positive primary breast tumours of the same patients before systemic (chemo/targeted therapy) treatment. The gene discussed is ERBB2; the disease is breast neoplasm.