ERBB2 and neoplasm: In this prospective multicenter trial of 56 patients with HER2-positive mBC, a combination of pretreatment HER2 imaging and early FDG-PET/CT was found to accurately predict morphological treatment response, leading to the conclusion that targeted HER2 imaging could be of great value both for the understanding of tumor heterogeneity and function as an aid in the selection of patients that would benefit from targeted treatment.