Activating mutations in surface growth factor receptor genes also seem to play a role in SGC tumorigenesis as about 14% of SGC showed mutations in genes as ALK, HER2, ERBB4, FGFR, cMET and RET. In two SDC without PIK3CA and HRAS mutation, mutations in HER2 and cMET occurred, respectively, and one SDC ex pleomorphic adenoma showed a RET mutation, pointing to alternative mechanisms in tumorigenesis of this tumor entity beyond PIK3CA and HRAS mutations. This evidence concerns the gene ERBB4 and neoplasm.