Genomic sequencing Investigation of 733 HER2-amplified Major and metastatic breast tumours uncovered substantial enrichment of mutations that activate RAS–MAPK signalling in Highly developed tumours dealt with with prior anti-HER2 therapies121. These mutations, together with NF1 and HER2 activating mutations, add to resistance to tucatinib and neratinib. Long term clinical investigations https://www.directivepublications.org/journal-of-clinical-breast-cancer/