Moreover, 89Zr-trastuzumab PET/ CT was performed in 20 patients with HER2-negative primary cancer and in 3 patients, increased uptake of 89Zr-tratsuzumab was found in metastases, indicating a change in HER2 expression between primary and metastatic lesions, allowing the anti-HER2 therapy adjustment [83]. This evidence concerns the gene ERBB2 and cancer.