Furthermore, like HER2, MET shows intratumoral heterogeneity: amplified and unamplified tumor cell clones occur in the same tumor distinguishable on a cell-by-cell level (Catenacci et al. 2011; Nagatsuma et al. 2015; Metzger et al. 2016), further compromising its usage as a predictive biomarker. This evidence concerns the gene ERBB2 and neoplasm.