Zirconium Zr 89 Trastuzumab or Zirconium Zr 89 DFO-Pertuzumab PET/CT in Identifying Unsuspected HER2 Positive Breast Metastases in Patients with HER2 Negative Breast Cancer
This clinical trial studies the use of zirconium Zr 89 trastuzumab or zirconium Zr 89 DFO-pertuzumab positron emission tomography (PET)/computed tomography (CT) in identifying unsuspected human epidermal growth factor receptor 2 (HER2) positive breast cancer that has spread from the primary HER2 negative breast cancer to other places in the body. HER2 is a protein that is over-expressed in HER2 positive breast cancer cells and helps them to grow. Treatments targeting HER2-expressing tumor cells have been effective in patients with HER2 positive breast cancer. PET/CT uses a radioactive label, a "tracer" called zirconium Zr 89 trastuzumab or zirconium Zr 89 DFO-pertuzumab, which may be able to locate HER2-expressing tumor cells. Diagnostic procedures, such as zirconium Zr 89 trastuzumab or zirconium Zr 89 DFO-pertuzumab PET/CT, may help to identify HER2 negative breast cancer patients that may benefit from treatments targeting HER2.