The first clinical trial with a 68Ga-labeled anti-HER2 nanobody as a molecular imaging tracer targeting the breast cancer marker HER2 is being finalized (EudraCT 2012-001135-31) and will generate the first in-human data on tolerability, dosimetry and its capacity to identify HER2 overexpressing lesions. This evidence concerns the gene ERBB2 and breast carcinoma.