ERBB2 and breast cancer: Furthermore, the expert panel (ASCO–College of American Pathologists) emphasized that “HER2 testing should still be optimized for the predictive purpose of identification of breast cancers with protein overexpression and/or gene amplification who could benefit from therapies aimed at disrupting HER2 signalling pathways” and stated that it is premature to change reporting terminology for lower levels of HER2 IHC expression [12].