This prospective study will investigate the potential usefulness of 99mTc-ABH2 SPECT/CT in the diagnostic performance and evaluation efficacy of breast cancer.

This study aims to assess the diagnostic performance of 99mTc-ABH2 SPECT/CT for the detection of HER2-positive primary breast cancer and possible metastases. Visual and semiquantitative methods will be utilized to evaluate the acquired SPECT/CT images. A comparative analysis of tumor imaging data and HER2 expression obtained by immunohistochemistry (IHC) and/or fluorescent in situ hybridization (FISH) analysis of biopsy samples will further be conducted. Results of HER2 expression imaging may have potential significance in screening and monitoring individuals for targeted therapy with monoclonal antibodies, like Trastuzumab.

Inclusion Criteria:

• clinically suspected primary breast cancer by mammography or ultrasonography and being able to sign the written informed consent form

Exclusion Criteria:

• pregnancy or lactation, impaired liver or kidney failure, and undergoing any preceding local or systemic therapies that might interfere HER2 binding