Based on the H10F peptide, a novel HER2-specific imaging probe, 99mTc-HP-Ark2, was developed for clinical practice, and a comparative study on 99mTc-HP-Ark2 SPECT/CT and 18F-FDG PET/CT was performed for the detection of HER2 expression in breast cancer patients. This evidence concerns the gene ERBB2 and breast cancer.