ERBB2 and gastric cancer: Although further large-scale clinical investigations are needed to understand the clinical prevalence in GC patients, our data on ZNF207-HER2, along with the discovery of two recurrent BAIAP2L1-BRAF, strongly indicate a large degree of molecular heterogeneity, even in the well-defined HER2-positive segment, representing potential de novo resistance to trastuzumab-based GC therapies.